Cannabidiol (cbd) Drug Interactions, Uses, Effectiveness, Safety & More
What is this page for?
First and foremost: how Cannabidiol (cbd) interacts with medications. The heart of this page is the interaction list — every drug Cannabidiol (cbd) is known to interact with, and how serious each one is.
But these pages have grown well beyond that into a full monograph — what Cannabidiol (cbd) is, what people use it for and how strong the evidence is, its safety and side effects, and answers to the questions we’re asked most — written and reviewed by the clinical staff at HelloPharmacist. It’s educational information from our licensed clinical databases, not medical advice, and we don’t sell or endorse products. Our editorial policy
Check Cannabidiol (cbd) against your medication
Add one medicationCannabidiol (cbd) Drug Interactions: The Bottom Line
From the HelloPharmacist Editorial Team · Updated July 2026Based on the available evidence, Cannabidiol (cbd) drug interactions carry a moderate risk of being clinically significant for many people, because CBD can slow down several enzymes the body uses to clear common medications. Every interaction in this profile is rated moderate, none major or minor, and a number of them are backed by solid human studies rather than theory alone.
The best-documented concerns involve seizure medications such as clobazam and brivaracetam, where human data show CBD can meaningfully raise drug levels and increase drowsiness. Citalopram levels also rose in a human study, with reports of fatigue and stomach upset. Perhaps most important, CBD substantially increased levels of everolimus, a narrow-margin transplant-type medicine, in a small clinical study. CBD may also add to the sedation caused by sleep aids and other calming medications.
The long list of interacting medications reflects CBD's effect on several drug-clearing enzymes, so most entries are predictions rather than proven problems. In fact, some anticipated interactions, like one involving dextromethorphan, did not occur when tested in people. Well-studied combinations deserve the attention; the rest are mostly theoretical possibilities.
Based on HelloPharmacist’s Cannabidiol (cbd) interaction data and reviewed under our editorial standards.
Drugs that interact with Cannabidiol (cbd)
1052 medications have a known interaction with Cannabidiol (cbd), graded by severity. Select any drug for the full evidence-based detail.
Don’t want to scroll the list? Just ask.
Tell us the medications you take and we’ll check each one against Cannabidiol (cbd) using our pharmacist-reviewed interaction data.
AI summaries are generated from our Cannabidiol (cbd) interaction data for education only — always confirm with your pharmacist. How we use AI
No drugs match “”.
What Severity, Likelihood & Evidence Mean
Severity — How Serious It Can Be
- Major. Clinically significant; generally best avoided, or used only under direct professional supervision.
- Moderate. May need monitoring, a dose adjustment, or separating the times you take each one.
- Minor. Generally not clinically significant, but still worth noting and mentioning to your pharmacist.
- No known interaction. Checked against our sources with nothing documented — not the same as proven safety.
Likelihood — How Well It’s Documented
- Likely. Well-controlled human studies have demonstrated the likely existence of this interaction
- Probable. Interaction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
- Possible. Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
- Unlikely. Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Where This Data Comes From
- Interaction records are evidence-graded and sourced from the Natural Medicines database (TRC Healthcare), the same reference used by pharmacists and hospitals.
- Each drug listed above links to the full report for that exact Cannabidiol (cbd) combination — clinical detail, likelihood, evidence level, and citations.
- Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.
The kinds of drugs Cannabidiol (cbd) affects
Every type of medication (drug category) Cannabidiol (cbd) is known to interact with. Open any category for the detail — or search your exact drug in the checker above.
Brivaracetam (Briviact)
Cannabidiol might increase brivaracetam levels.
Brivaracetam is a substrate of CYP2C19. Clinical research shows that cannabidiol inhibits CYP2C19. Evidence from a case series shows that patients receiving cannabidiol experienced a 95% to 280% increase in brivaracetam levels.
Caffeine
Cannabidiol can increase caffeine levels.
Caffeine is a substrate of CYP1A2, and cannabidiol has been shown to inhibit CYP1A2 metabolism. A pharmacokinetic study in healthy adults shows that taking oral cannabidiol, starting at 250 mg once daily and titrating to 750 twice daily over a total of 24 days, increases the peak serum level of caffeine by 15% and the overall exposure to caffeine by 95% after a single dose of caffeine 200 mg taken on day 23. Other clinical research also shows that cannabidiol modestly increases the area under the curve of caffeine but does not increase peak serum levels of caffeine.
Carbamazepine (Tegretol)
Cannabidiol might increase carbamazepine levels.
Research in murine animal models shows that giving a single oral dose of cannabidiol 50 mg/kg with carbamazepine 80 mg/kg increases carbamazepine's area under the curve (AUC) by 53% when compared with control. A higher single dose of cannabidiol 120 mg/kg has a similar effect on carbamazepine levels. Multiple doses of cannabidiol have a slightly larger effect. Giving cannabidiol daily for 14 days increases the AUC of carbamazepine by 66%.
Citalopram (Celexa)
Cannabidiol can increase citalopram levels.
A small open-label study in young adults stabilized on citalopram or escitalopram shows that taking adjunctive cannabidiol 200-800 mg daily for 12 weeks increases plasma concentrations of citalopram from an average of 42 ng/mL at baseline to an average of 79 ng/mL at 8 weeks and 63 ng/mL at 12 weeks. Patients reported fatigue and gastrointestinal disturbances; there were no reports suggestive of serotonergic toxicity. In vitro evidence suggests that this interaction may be due to inhibition of cytochrome P450 (CYP) 2C19 and 3A4 by cannabidiol. This finding is limited due to small study size and large interindividual variability.
Clobazam (Onfi)
Cannabidiol might increase levels of clobazam and increase the occurrence of somnolence.
In clinical studies, concomitant administration of cannabidiol and clobazam is associated with up to a 60% increase in serum levels of N-desmethylclobazam, the primary active metabolite of clobazam. This increased concentration is likely due to inhibition of CYP2C19 by cannabidiol. However, the interaction does not appear to be dose-dependent. In children and adults, concomitant use of cannabidiol and clobazam is associated with an increased occurrence of somnolence.
Cns Depressants
Theoretically, cannabidiol might have additive effects if used with other CNS depressants.
Preliminary clinical research, case reports, and animal studies suggest that high dose cannabidiol has sedative and hypnotic effects. Theoretically, concomitant use of cannabidiol with drugs with sedative and anesthetic properties may cause additive therapeutic and adverse effects.
Cytochrome P450 1A2 (Cyp1A2) Substrates
Cannabidiol may increase levels of drugs metabolized by CYP1A2.
In vitro research shows that cannabidiol inhibits CYP1A2. Furthermore, clinical studies show that cannabidiol may inhibit the metabolism of caffeine, a CYP1A2 substrate. Two pharmacokinetic studies in healthy adults show that taking cannabidiol dosed 640 mg once up to 750 twice daily increases the area under the curve of caffeine. However, results are mixed over whether cannabidiol impacts peak serum levels of caffeine.
Cytochrome P450 2A6 (Cyp2A6) Substrates
Theoretically, cannabidiol might increase levels of drugs metabolized by CYP2A6.
In vitro research shows that cannabidiol inhibits CYP2A6. However, this interaction has yet to be reported in humans. Until more is known, use with caution. Theoretically, concomitant use of cannabidiol with CYP2A6 substrates might increase the risk for adverse effects from these substrates.
Cytochrome P450 2B6 (Cyp2B6) Substrates
Theoretically, cannabidiol might increase levels of drugs metabolized by CYP2B6.
In vitro research shows that cannabidiol inhibits CYP2B6. However, this interaction has yet to be reported in humans. Until more is known, use with caution. Theoretically, concomitant use of cannabidiol with CYP2B6 substrates might increase the risk for adverse effects from these substrates.
Cytochrome P450 2C19 (Cyp2C19) Inducers
Theoretically, CYP2C19 inducers might decrease cannabidiol levels.
Cannabidiol is a substrate of CYP2C19 enzymes. Theoretically, drugs that induce CYP2C19 enzymes might decrease the levels and effects of cannabidiol.
Cytochrome P450 2C19 (Cyp2C19) Inhibitors
Theoretically, CYP2C19 inhibitors might increase cannabidiol levels.
Cannabidiol is a substrate of CYP2C19 enzymes. Theoretically, drugs that inhibit CYP2C19 enzymes might increase levels of cannabidiol, increasing its effects and adverse effects.
Cytochrome P450 2C19 (Cyp2C19) Substrates
Cannabidiol may increase levels of drugs metabolized by CYP2C19.
Research shows that cannabidiol inhibits CYP2C19. In clinical studies and case reports, cannabidiol use resulted in significant increases in the serum levels of topiramate, methadone, citalopram, omeprazole, and N-desmethylclobazam, the primary active metabolite of clobazam. These chemicals are metabolized by CYP2C19. Concomitant use of cannabidiol with CYP2C19 substrates may increase the risk for adverse effects from these substrates.
Cytochrome P450 2C8 (Cyp2C8) Substrates
Theoretically, cannabidiol might increase levels of drugs metabolized by CYP2C8.
In vitro research shows that cannabidiol inhibits CYP2C8. However, this interaction has yet to be reported in humans. Until more is known, use with caution. Theoretically, concomitant use of cannabidiol with CYP2C8 substrates might increase the risk for adverse effects from these substrates.
Cytochrome P450 2C9 (Cyp2C9) Substrates
Cannabidiol may increase levels of drugs metabolized by CYP2C9.
In vitro and animal research shows that cannabidiol inhibits CYP2C9. In human studies, cannabidiol has been associated with an increase in plasma levels of topiramate and losartan, CYP2C9 substrates. Concomitant use of cannabidiol with CYP2C9 substrates may increase the risk for adverse effects from these substrates.
Cytochrome P450 2D6 (Cyp2D6) Substrates
Theoretically, cannabidiol might increase levels of drugs metabolized by CYP2D6.
In vitro research shows that cannabidiol inhibits CYP2D6. Theoretically, concomitant use of cannabidiol with CYP2D6 substrates might increase the risk for adverse effects from these substrates. However, a clinical crossover trial in healthy adults shows that cannabidiol does not inhibit dextromethorphan, a substrate of CYP2D6.
Cytochrome P450 2E1 (Cyp2E1) Substrates
Theoretically, cannabidiol might increase levels of drugs metabolized by CYP2E1.
In vitro research shows that cannabidiol inhibits CYP2E1. So far, this interaction has not been reported in humans.
Cytochrome P450 3A4 (Cyp3A4) Inducers
Theoretically, CYP3A4 inducers might decrease cannabidiol levels.
Cannabidiol is a substrate of CYP3A4 enzymes. Theoretically, drugs that induce CYP3A4 enzymes might reduce the levels and effects of cannabidiol.
Cytochrome P450 3A4 (Cyp3A4) Inhibitors
Theoretically, CYP3A4 inhibitors might increase cannabidiol levels.
Cannabidiol is a substrate of CYP3A4 enzymes. Theoretically, drugs that inhibit CYP3A4 enzymes might increase levels of cannabidiol, increasing its effects and adverse effects.
Cytochrome P450 3A4 (Cyp3A4) Substrates
Cannabidiol may increase levels of drugs that are metabolized by CYP3A4.
In vitro and animal research shows that cannabidiol inhibits CYP3A4. In human studies and case reports, cannabidiol has been associated with an increase in plasma levels of the CYP3A4 substrates zonisamide, tacrolimus, everolimus, citalopram, midazolam, and methadone.
Eslicarbazepine (Aptiom)
Cannabidiol might increase eslicarbazepine levels.
In clinical research, concomitant administration of cannabidiol and eslicarbazepine is associated with a modest increase in plasma levels of eslicarbazepine. The mechanism for this interaction is unknown; eslicarbazepine is metabolized via glucuronidation. Eslicarbazepine levels stayed within the normal range and did not require dose adjustment. However, caution should be exercised when cannabidiol and eslicarbazepine are taken together.
Everolimus (Zortress)
Cannabidiol may increase everolimus levels.
Everolimus is a substrate of CYP3A4 enzymes. Cannabidiol has been shown to inhibit CYP3A4. A very small open-label clinical study shows that cannabidiol 12.5 mg/kg twice daily increases the area under the curve of a single dose of everolimus by about 2.5-fold. A retrospective study in children taking everolimus for tuberous sclerosis has found that adding treatment with cannabidiol increases everolimus serum concentration by a median of 9.8 ng/mL. In a case report, a 6-year-old girl stable on everolimus with refractory tonic seizures was started on cannabidiol titrated up to 200 mg daily for 6 weeks. This led to elevated levels of everolimus.
Fluoxetine (Prozac)
Cannabidiol might increase fluoxetine levels in certain patients.
In one case report, a 17-year-old male with autism previously stabilized on fluoxetine 20 mg daily developed insomnia, agitation, hyperactivity, yelling, and worsening symptoms of obsessive-compulsive disorder after taking cannabidiol 18 mg twice daily for 2 weeks. The patient was found to be a poor cytochrome P450 2D6 (CYP2D6) metabolizer (CYP2D6*4/*4). Fluoxetine is primarily metabolized by CYP2D6, and to a lesser extent, by CYP2C9. Although fluoxetine levels weren't measured, it was hypothesized that the lack of CYP2D6 activity resulted in fluoxetine being metabolized solely by CYP2C9, which was subsequently inhibited by cannabidiol. This would have increased levels of fluoxetine, resulting in adverse effects. Further research is needed to confirm this complex gene-drug interaction cascade.
Glucuronidated Drugs
Cannabidiol might increase levels of certain glucuronidated drugs.
In vitro research shows that cannabidiol inhibits uridine diphosphoglucuronosyl transferase (UGT) 1A9 and UGT2B7, enzymes responsible for glucuronidation. Theoretically, this could decrease the clearance and increase levels of glucuronidated drugs.
Lithium
Cannabidiol might precipitate lithium toxicity, but the evidence is limited to a single case report.
In a case report, a 13-year-old male with Lennox-Gastaut syndrome and autism, stable on lithium for one year, presented to the hospital with lithium toxicity after an increase in daily cannabidiol dose from 5 mg/kg to 10 mg/kg. Theoretically, lithium toxicity might have occurred due to cannabidiol-induced renal dysfunction.
Losartan (Cozaar)
Cannabidiol may increase levels of losartan.
A crossover clinical study shows that taking cannabidiol 640 mg once increases area under the curve of losartan, a CYP2C9 substrate, by 77%.
Methadone (Dolophine)
Cannabidiol might increase levels of methadone, but the evidence is limited to a single case report.
In a case report, a 13-year-old female with chronic cancer pain who was previously stabilized on methadone 7.5 mg twice daily presented to the emergency room with opioid-related side effects. She had begun experiencing increased sleepiness and fatigue after being given cannabidiol oil 1.5 grams orally in six divided doses daily by her parents. Her serum levels of methadone had risen to 271 ng/mL but decreased to 124 ng/mL after discontinuation of cannabidiol. This coincided with resolution of excessive sleepiness and fatigue. Theoretically, cannabidiol increases levels of methadone by inhibiting cytochrome P450 3A4 (CYP3A4) and CYP2C19 enzymes, which metabolize methadone.
Midazolam (Versed)
Cannabidiol may increase levels of midazolam.
A crossover clinical study shows that taking cannabidiol 640 mg once increases area under the curve of midazolam by 56%, likely by inhibiting CYP3A.
Omeprazole (Prilosec)
Cannabidiol may increase levels of omeprazole.
A crossover clinical study shows that taking cannabidiol 640 mg once increases area under the curve of omeprazole by 207%, likely by inhibiting CYP2C19.
Rufinamide (Banzel)
Cannabidiol might increase rufinamide levels.
In clinical research, concomitant administration of cannabidiol and rufinamide is associated with a modest increase in plasma levels of rufinamide. The mechanism for this interaction is unknown; rufinamide is metabolized via carboxyl esterases. Rufinamide levels stayed within the normal range and did not require dose adjustment. However, caution should be exercised when cannabidiol and rufinamide are taken together.
Sirolimus (Rapamune)
Cannabidiol might increase sirolimus levels.
Sirolimus is a substrate of cytochrome P450 3A4 (CYP3A4) enzymes. Cannabidiol has been shown to inhibit CYP3A4 enzymes. A retrospective study in children taking sirolimus for tuberous sclerosis has found that adding treatment with cannabidiol increases serum sirolimus concentration by a median of 5.1 ng/mL.
Stiripentol (Diacomit)
Cannabidiol can increase stiripentol levels.
Two clinical pharmacokinetic studies in patients stabilized on stiripentol shows that adding cannabidiol, 750 mg twice daily for 3-10 days or up to 20 mg/kg daily for 24 days, increases the average maximum concentration of stiripentol by 17% to 28% and the average area under the curve by 30% to 55% when compared with taking stiripentol alone. The mechanism for this interaction is unknown; cannabidiol might inhibit cytochrome P450 2C19 (CYP2C19) and/or UDP-glucuronosyltransferase (UGT) isoforms, which metabolize stiripentol. Although there were no adverse clinical outcomes, caution should be exercised when cannabidiol and stiripentol are taken together.
Tacrolimus (Prograf)
Cannabidiol might increase tacrolimus levels.
Tacrolimus is a cytochrome P450 3A4 (CYP3A4) substrate. Cannabidiol has been shown to inhibit CYP3A4 enzymes. In a case report, a patient stabilized on tacrolimus experienced about a 3-fold increase in tacrolimus concentrations after starting to take cannabidiol 2000-2900 mg daily for epilepsy.
Tamoxifen (Nolvadex)
Chronic use of cannabidiol 40 mg daily might modestly reduce levels of tamoxifen's active metabolites.
In one case report, a 50-year-old female who was taking tamoxifen 20 mg daily for the past 5 years and cannabidiol 40 mg daily for about four months, presented with a 9.2% increase in N-desmethyltamoxifen and an 18.8% increase in endoxifen levels after discontinuing cannabidiol for 67 days. Theoretically, cannabidiol may have modestly inhibited cytochrome P450 3A4 (CYP3A4) and CYP2D6, which metabolize tamoxifen into N-desmethyltamoxifen and endoxifen, respectively. Cannabidiol discontinuation may have resulted in a return to normal enzyme activity.
Topiramate (Topamax)
Cannabidiol might increase topiramate levels.
In clinical research, concomitant administration of cannabidiol and topiramate, a CYP2C9 and CYP2C19 substrate, is associated with a modest increase in plasma levels of topiramate. Topiramate levels stayed within the normal range and did not require dose adjustment. However, caution should be exercised when cannabidiol and topiramate are taken together.
Valproate
Cannabidiol might increase the risk of hepatotoxicity and thrombocytopenia with valproic acid.
In clinical research, concomitant administration of valproic acid and cannabidiol is associated with elevated liver transaminases and rare cases of thrombocytopenia. Liver transaminase levels and platelet counts should be closely monitored when cannabidiol and valproic acid are taken together. Liver transaminase elevation appears to be mild in the majority of cases; however, severe elevations can occur. At least 15 cases of thrombocytopenia have been reported following concomitant administration of valproic acid and cannabidiol. While thrombocytopenia is a known adverse effect with valproic acid, the risk may be modestly higher when cannabidiol and valproic acid are administered concomitantly. It is unclear if and how cannabidiol contributes to the risk of these adverse events, as there does not appear to be a direct pharmacokinetic interaction. Pharmacokinetic studies in humans show that coadministration of valproate with cannabidiol does not have clinically meaningful effects on levels of valproate or its metabolite 4-ene-VPA.
Warfarin (Coumadin)
Cannabidiol might increase warfarin levels.
There are at least two case reports of patients who were previously stable on warfarin presenting with a supratherapeutic International Normalized Ratio (INR) after starting cannabidiol (Epidiolex) titrated up to a dose of 20 mg/kg daily. Warfarin dose reductions of 20% to 30% were required to normalize the INR. Cannabidiol may have inhibited cytochrome P450 2C9 (CYP2C9), resulting in decreased warfarin metabolism and increased levels.
Zonisamide (Zonegran)
Cannabidiol might increase zonisamide levels.
In clinical research, concomitant administration of cannabidiol and zonisamide, a cytochrome P450 3A4 (CYP3A4) substrate, is associated with a modest increase in plasma levels of zonisamide. Zonisamide levels stayed within the normal range and did not require dose adjustment. However, caution should be exercised when cannabidiol and zonisamide are taken together.
Cannabidiol (cbd): Uses, Safety & Side Effects
CBD is a compound from the cannabis (hemp) plant that does not cause a 'high.' It has strong evidence only for certain rare seizure disorders (as a prescription drug), while most other popular uses are still backed by limited or early research. Product quality varies a lot, so talk with your pharmacist or doctor before using it, especially if you take other medicines.
- Scientific name
- Cannabis sativa
- Family
- Cannabaceae
- Part used
- Flowers, leaves, and stalks of the hemp plant (extracted compound)
- Common forms
- Oils and tinctures, capsules, gummies, topical creams, vape liquids, and a prescription solution
- Anxiety and stress
- Sleep problems
- Chronic pain
- Certain seizure disorders
- Inflammation
Popular and traditional uses — not proof it works. See “Uses & effectiveness” below for the evidence.
CBD is generally well tolerated but can cause side effects and quality varies between products.
When used orally. The US Food and Drug Administration (FDA) strongly advises against the use of cannabidiol during pregnancy. Cannabidiol products mig...
Read the full pregnancy detailWhen used orally. The US Food and Drug Administration (FDA) strongly advises against the use of cannabidiol during pregnancy. Cannabidiol products mig...
Read the full breastfeeding detailPregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center). Safety guidance is general; always confirm with your pharmacist or doctor for your situation.
Overview
Cannabidiol (CBD) is one of many natural compounds found in the cannabis plant (Cannabis sativa). Most CBD products sold today come from hemp, a type of cannabis that contains very little THC, the compound that causes a 'high.' Because of this, CBD by itself does not make you feel intoxicated.
CBD is sold in many forms, including oils, tinctures, gummies, capsules, and creams. People use it for a wide range of reasons, such as easing anxiety, improving sleep, or relieving pain. There is also a prescription form of CBD that doctors use to treat certain rare seizure disorders.
It is important to know that the supplement market for CBD is not tightly regulated. The amount of CBD in a product may differ from what the label says, and some products may contain THC or other unwanted ingredients.
How it works
The body has a system called the endocannabinoid system, which helps regulate things like mood, pain, sleep, and the immune response. CBD interacts with this system, but in a complex way that scientists are still working to understand.
Unlike THC, CBD does not strongly bind to the main cannabinoid receptors that cause a 'high.' Instead, researchers believe it affects several other receptors and signaling pathways, which may influence pain, anxiety, and inflammation. CBD may also affect serotonin signaling, which is linked to mood.
Much of what we know about how CBD works comes from laboratory and animal studies. These findings are promising but do not always translate into clear benefits in people.
Does Cannabidiol (cbd) work?
How to read these evidence grades
Natural Medicines’ 7-point scale. We show each rating’s label word-for-word.
Likely Effective Epilepsy
A specific prescription cannabidiol product, Epidiolex (Jazz Pharmaceuticals), is FDA-approved for use in Lennox-Gastaut syndrome, Dravet syndrome, or tuberous sclerosis complex and clinical research has found it to be effective for reducing seizures in a variety of types of treatment-resistant epilepsy. It is unclear if other cannabidiol products are beneficial for these conditions.
Also studied for 56 conditions — evidence insufficient to rate
Insufficient Reliable Evidence To Rate Alzheimer disease
Oral cannabidiol has only been evaluated as a component of a cannabis extract; its effect when used alone is unclear.
Insufficient Reliable Evidence To Rate Aromatase inhibitor-induced arthralgia
It is unclear if oral cannabidiol reduces joint pain in those with aromatase inhibitor-induced arthralgia.
Insufficient Reliable Evidence To Rate Athletic performance
It is unclear if oral cannabidiol is beneficial for improving athletic performance.
Insufficient Reliable Evidence To Rate Atopic dermatitis (eczema)
It is unclear if topical cannabidiol is beneficial for reducing eczema symptoms.
Insufficient Reliable Evidence To Rate Autism spectrum disorder
It is unclear if cannabidiol is beneficial for autism spectrum disorder.
Insufficient Reliable Evidence To Rate Bipolar disorder
Although there has been interest in using cannabidiol for bipolar disorder, there is insufficient reliable information about the clinical effects of cannabidiol for this purpose.
Insufficient Reliable Evidence To Rate Cachexia
Oral cannabidiol has only been evaluated as a component of a cannabis extract; its effect when used alone is unclear.
Insufficient Reliable Evidence To Rate Cancer-related fatigue
More research is needed to determine if non-inhaled cannabidiol is beneficial in patients with cancer-related pain that is not adequately controlled with standard treatment.
Insufficient Reliable Evidence To Rate Cancer-related pain
More research is needed to determine if non-inhaled cannabidiol is beneficial in patients with cancer-related pain that is not adequately controlled with standard treatment.
Insufficient Reliable Evidence To Rate Canker sores
It is unclear if topical cannabidiol is beneficial for recurrent canker sores.
Insufficient Reliable Evidence To Rate Cannabis use disorder
It is unclear if oral cannabidiol is beneficial for reducing cannabis use in patients with cannabis use disorder.
Insufficient Reliable Evidence To Rate Chemotherapy-induced nausea and vomiting (CINV)
It is unclear if a cannabis oromucosal spray or oral cannabis extract, providing standard doses of cannabidiol in combination with other ingredients, is beneficial for the prevention of CINV.
Insufficient Reliable Evidence To Rate Chemotherapy-induced peripheral neuropathy
It is unclear if oral or topical cannabidiol (CBD) is beneficial for treating chemotherapy-induced peripheral neuropathy.
Insufficient Reliable Evidence To Rate Chemotherapy-related taste changes
It is unclear if oral cannabidiol is beneficial for improving taste- related changes from chemotherapy.
Insufficient Reliable Evidence To Rate Cocaine dependence
It is unclear if oral cannabidiol is beneficial for reducing anxiety in patients with cocaine use disorder.
Insufficient Reliable Evidence To Rate Cognitive function
It is unclear if oral, sublingual, or inhaled cannabidiol improves cognitive function in healthy adults.
Insufficient Reliable Evidence To Rate Coronavirus disease 2019 (COVID-19)
A small clinical study suggests that oral cannabidiol is not beneficial in patients with mild to moderate COVID-19.
Insufficient Reliable Evidence To Rate Crohn Disease
It is unclear if oral cannabidiol is beneficial for Crohn disease.
Insufficient Reliable Evidence To Rate Dementia
It is unclear if oral cannabidiol is beneficial for behavioral and mood symptoms in dementia.
Insufficient Reliable Evidence To Rate Diabetes
It is unclear if oral cannabidiol is beneficial for glucose and lipid management in patients with type 2 diabetes.
Insufficient Reliable Evidence To Rate Dyspepsia
It is unclear if oral cannabidiol is beneficial for dyspepsia.
Insufficient Reliable Evidence To Rate Dystonia
It is unclear if oral cannabidiol is beneficial for dystonia of various etiologies.
Insufficient Reliable Evidence To Rate Essential tremor
It is unclear if oral cannabidiol is beneficial in adults with this condition.
Insufficient Reliable Evidence To Rate Exercise-induced muscle damage
It is unclear if oral cannabidiol helps to reduce muscle damage from exercise in trained athletes or untrained adults.
Insufficient Reliable Evidence To Rate Exercise-induced muscle soreness
Cannabidiol has only been studied in combination with other ingredients; its effect when used alone is unclear.
Insufficient Reliable Evidence To Rate Fibromyalgia
Inhaled cannabidiol has only been evaluated as a component of a cannabis extract; its effect when used alone is unclear.
Insufficient Reliable Evidence To Rate Fragile X syndrome
It is unclear if topical cannabidiol is beneficial in children with this condition.
Insufficient Reliable Evidence To Rate Gastroparesis
It is unclear if cannabidiol is beneficial for gastroparesis.
Insufficient Reliable Evidence To Rate Graft-versus-host disease (GVHD)
It is unclear if cannabidiol prevents or delays GVHD.
Insufficient Reliable Evidence To Rate Huntington disease
It is unclear if oral cannabidiol is beneficial for this condition.
Insufficient Reliable Evidence To Rate Hypertension
It is unclear if oral cannabidiol is beneficial for hypertension.
Insufficient Reliable Evidence To Rate Insomnia
It is unclear if oral cannabidiol is beneficial for preventing or treating insomnia.
Insufficient Reliable Evidence To Rate Irritable bowel syndrome (IBS)
It is unclear if oral cannabidiol is beneficial for improving pain in IBS.
Insufficient Reliable Evidence To Rate Kidney stones (nephrolithiasis)
It is unclear if cannabidiol is beneficial for post-ureteroscopy pain.
Insufficient Reliable Evidence To Rate Multiple sclerosis (MS)
A specific cannabis oromucosal spray and oral cannabis extract, providing standard doses of cannabidiol in combination with delta-9-tetrahydrocannabinol (THC), may modestly reduce spasticity in patients with MS. The effect of cannabidiol alone on symptoms of MS is unclear.
Insufficient Reliable Evidence To Rate Neuropathic pain
It is unclear if oral cannabidiol is beneficial for neuropathic pain.
Insufficient Reliable Evidence To Rate Obesity
It is unclear if an oral cannabidiol-rich hemp oil extract helps to improve weight loss.
Insufficient Reliable Evidence To Rate Opioid withdrawal
It is unclear if cannabidiol is beneficial for reducing cravings associated with heroin use disorder.
Insufficient Reliable Evidence To Rate Osteoarthritis
It is unclear if oral or topical cannabidiol is beneficial for improving pain in patients with osteoarthritis.
Insufficient Reliable Evidence To Rate Parkinson disease
It is unclear if cannabidiol is beneficial for improving symptoms, disease severity, or reducing psychosis in adults with this condition.
Insufficient Reliable Evidence To Rate Periodontitis
It is unclear if topical cannabidiol is beneficial for gingival health in individuals with periodontitis.
Insufficient Reliable Evidence To Rate Peripheral neuropathy
It is unclear if oral cannabidiol is beneficial for neuropathic pain.
Insufficient Reliable Evidence To Rate Post-traumatic stress disorder (PTSD)
It is unclear if oral cannabidiol is beneficial in patients with PTSD.
Insufficient Reliable Evidence To Rate Postoperative pain
Small clinical studies suggest that oral or topical cannabidiol may not significantly affect postoperative pain.
Insufficient Reliable Evidence To Rate Pre-procedural anxiety
It is unclear if oral cannabidiol is beneficial for reducing pre-procedural anxiety.
Insufficient Reliable Evidence To Rate Psoriasis
It is unclear if oral cannabidiol is beneficial for psoriasis.
Insufficient Reliable Evidence To Rate Psoriatic arthritis
It is unclear if oral cannabidiol is beneficial for improving pain in patients with psoriatic arthritis.
Insufficient Reliable Evidence To Rate Psychological well-being
It is unclear if an oral cannabidiol-rich hemp oil extract improves psychological well-being in healthy patients.
Insufficient Reliable Evidence To Rate Psychosis
It is unclear if inhaling cannabidiol is beneficial in patients with acute psychosis.
Insufficient Reliable Evidence To Rate Rapid eye movement sleep behavior disorder (RBD)
It is unclear if oral cannabidiol is beneficial for the management of Parkinson disease-related RBD.
Insufficient Reliable Evidence To Rate Rheumatoid arthritis (RA)
It is unclear whether an oromucosal cannabis spray containing cannabidiol and delta-9-tetrahydrocannabinol (THC) improves RA symptoms.
Insufficient Reliable Evidence To Rate Schizophrenia
Small clinical studies suggest that oral cannabidiol may modestly reduce symptoms and improve wellbeing in patients with schizophrenia or schizophreniform psychosis.
Insufficient Reliable Evidence To Rate Social anxiety disorder
It is unclear if oral cannabidiol is beneficial for reducing overall anxiety or anxiety during public speaking; the available research is conflicting.
Insufficient Reliable Evidence To Rate Temporomandibular disorders (TMD)
A small clinical study suggests that topical cannabidiol may reduce TMD pain.
Insufficient Reliable Evidence To Rate Tobacco and nicotine dependence
It is unclear if cannabidiol reduces cravings for cigarettes or limits nicotine withdrawal symptoms.
Insufficient Reliable Evidence To Rate Tourette syndrome
Oral cannabidiol has only been evaluated in combination with other cannabinoids; its effect when used alone is unclear.
Source & disclaimer. Effectiveness ratings and evidence summaries are provided by Natural Medicines (Therapeutic Research Center) and shown as licensed. Where Natural Medicines hasn’t rated a use, HelloPharmacist’s pharmacists may add their own reviewed rating and evidence (each such entry is labeled). This is educational information, not medical advice — talk with your pharmacist or doctor before starting, stopping, or changing a supplement.
Safety & precautions
CBD is generally considered well tolerated for most adults when used short term. However, it is not risk-free. People with liver problems should be especially careful, since high doses of CBD can affect liver function. Anyone taking other medicines should check with a pharmacist or doctor first.
Because product quality varies, choose products that have been tested by an independent lab and show a certificate of analysis. This helps confirm the CBD content and that the product is free of harmful contaminants.
Pregnancy and breastfeeding: Avoid CBD if you are pregnant or breastfeeding. Health authorities advise against it because we do not have enough safety data, and CBD may reach the baby through the placenta or breast milk.
Talk with your doctor before giving CBD to children, except for prescription products used under medical supervision.
Side effects
The most commonly reported side effects of CBD include drowsiness, tiredness, diarrhea, changes in appetite, and changes in weight. Some people also notice dry mouth or feeling lightheaded.
A more serious but less common concern is liver injury, which has been seen mostly at higher doses or with the prescription form. Signs to watch for include yellowing of the skin or eyes, dark urine, or pain in the upper right belly. Stop CBD and seek medical care if these occur.
If you experience any unusual symptoms while taking CBD, stop using it and contact your healthcare provider.
Cannabidiol (cbd): Reported Adverse Effects
Documented safety reports on Cannabidiol (cbd) from the evidence-graded Natural Medicines (TRC Healthcare) database, shown word-for-word from the licensed record.
Orally, cannabidiol seems to be well tolerated.
Most Common Adverse Effects:
Orally: For prescription cannabidiol (Epidiolex), somnolence in up to 30% of patients and diarrhea in up to 24% of patients. Also, decreased appetite, drowsiness, dry mouth, fatigue, pyrexia, vomiting, and weight loss. Higher doses over 15-20 mg/kg daily are more likely to cause somnolence, decreased appetite, diarrhea, liver enzyme elevations, and weight loss. Pharmacogenetic variation may also affect susceptibility to certain adverse effects, particularly diarrhea, sedation, and abnormal liver enzyme levels.
Serious Adverse Effects (Rare):
Orally: There have been rare case reports of hepatitis, respiratory depression, and pneumonia.
Anxiety Psychiatric
Limited research suggests that consuming large amounts of cannabidiol might increase the adverse effects of delta-9-tetrahydrocannabinol (THC). A small study in healthy adults shows that consumption of brownies containing cannabidiol 640 mg plus THC 20 mg increases feelings of anxiety, paranoia, and irritability when compared with brownies containing only THC 20 mg.
Cancer Pulmonary/Respiratory
Orally, cannabidiol oil has been associated with rare respiratory depression and increased odds of pneumonia. In a case report, a 56-year-old obese male presented to the emergency room with severe respiratory depression 3 hours after consuming two packages of gummies labeled to contain cannabidiol 370 mg. Symptoms included respiratory acidosis, slurred speech, bradycardia, and vomiting. The patient was treated with supportive care. It is uncertain whether these effects were caused by cannabidiol or other adulterant substances in the gummies.
A small clinical trial in patients with cancer found that taking cannabidiol (GD-Cann C, Norwood, South Australia) in median doses of 400 mg daily for up to 2 weeks results in an increased number of patients with dyspnea when compared with placebo.
Using a specific oromucosal spray that contains cannabidiol 2.5 mg and delta-9-tetrahydrocannabinol 2.7 mg (THC) per actuation (Sativex, GW Pharmaceuticals) may cause pharyngitis, hoarseness, and throat irritation.
- Bass J, Linz DR. A Case of Toxicity from Cannabidiol Gummy Ingestion. Cureus. 2020;12(4):e7688.
- Chesney E, Oliver D, Green A, et al. Adverse effects of cannabidiol: a systematic review and meta-analysis of randomized clinical trials. Neuropsychopharmacology. 2020.
- Patel AD, Mazurkiewicz-Beldzinska M, Chin RF, et al. Long-term safety and efficacy of add-on cannabidiol in patients with Lennox-Gastaut syndrome: Results of a long-term open-label extension trial. Epilepsia 2021;62(9):2228-2239.
- Scheffer IE, Halford JJ, Miller I, et al. Add-on cannabidiol in patients with Dravet syndrome: Results of a long-term open-label extension trial. Epilepsia 2021;62(10):2505-2517.
- Hardy J, Greer R, Huggett G, Kearney A, Gurgenci T, Good P. Phase IIb Randomized, Placebo-Controlled, Dose-Escalating, Double-Blind Study of Cannabidiol Oil for the Relief of Symptoms in Advanced Cancer (MedCan1-CBD). J Clin Oncol 2022.
- Rog, D. J., Nurmikko, T. J., Friede, T., and Young, C. A. Randomized, controlled trial of cannabis-based medicine in central pain in multiple sclerosis. Neurology 9-27-2005;65(6):812-819.
Cognitive function Neurologic/CNS
Orally, cannabidiol has been most commonly reported to cause somnolence, sedation, dizziness, agitation, and fatigue, with a significantly higher incidence when used in conjunction with clobazam. Hallucinations, delusions, confusion, and slurred speech have been reported in a Poison Control Center report. Other symptoms reported in clinical research include low mood, temperature dysregulation, and insomnia, although the prevalence and clinical significance is unclear. Cannabidiol has been reported to cause sedation and psychomotor slowing in some patients. In an observational study, sedation occurred in approximately 17% of patients who took prescription cannabidiol oil (Epidiolex) and was the reason for discontinuation in about 1 in 5 patients. Pharmacogenetic variation has been shown to affect susceptibility to cannabidiol-associated sedation. There is concern that cannabidiol can cause cognitive impairments when used for a long duration. However, cannabidiol does not seem to negatively impact cognition in adults with treatment-resistant epilepsy used for up to one-year. Cannabis extract oromucosal spray that contains cannabidiol 2.5 mg and delta-9-tetrahydrocannabinol (THC) 2.7 mg per actuation (Sativex, GW Pharmaceuticals) can cause dizziness, lightheadedness, sleepiness, and fatigue. Additionally, a small study in healthy adults shows that consumption of brownies containing cannabidiol 640 mg plus THC 20 mg increases feelings of sedation and memory impairment when compared with brownies containing only THC 20 mg. In children, cannabidiol oil has caused drowsiness, fatigue, sedation, and gait disturbance.
Cannabidiol does not seem to be associated with withdrawal symptoms. Clinical research in healthy volunteers taking cannabidiol daily for 4 weeks shows that stopping cannabidiol abruptly does not cause withdrawal symptoms.
Limited research suggests that cannabidiol does not cause driving impairment. A small study has found that inhaling vaporized cannabis containing cannabidiol 13.75 mg does not increase lane weaving when compared with placebo. The lane weaving seen in those inhaling this product was equivalent to having a blood alcohol concentration (BAC) of 0.02%, which is below the lower limit of clinically relevant impairment that is considered to occur with a BAC of 0.05%. Other research shows that taking a single oral dose of cannabidiol (GD Cann-C; GD Pharma Pty Ltd) 15 mg, 300 mg, or 1500 mg, confirmed to be devoid of delta-9-tetrahydrocannabinol (THC) and other cannabinoids, does not affect cognitive function or driving performance after 15-240 minutes when compared with placebo. The validity of these findings is limited because these studies only tested a single dose of cannabidiol, which does not mimic real-world use.
- Carlini EA, Cunha JM. Hypnotic and antiepileptic effects of cannabidiol. J Clin Pharmacol 1981;21(8-9 Suppl):417S-27S.
- Laux LC, Bebin EM, Checketts D, et al. Long-term safety and efficacy of cannabidiol in children and adults with treatment resistant Lennox-Gastaut syndrome or Dravet syndrome: Expanded access program results. Epilepsy Res. 2019;154:13-20.
- Klotz KA, Grob D, Hirsch M, Metternich B, Schulze-Bonhage A, Jacobs J. Efficacy and Tolerance of Synthetic Cannabidiol for Treatment of Drug Resistant Epilepsy. Front Neurol. 2019 Dec 10;10:1313.
- Chesney E, Oliver D, Green A, et al. Adverse effects of cannabidiol: a systematic review and meta-analysis of randomized clinical trials. Neuropsychopharmacology. 2020.
- Leehey MA, Liu Y, Hart F, et al. Safety and Tolerability of Cannabidiol in Parkinson Disease: An Open Label, Dose-Escalation Study. Cannabis Cannabinoid Res. 2020;5(4):326-336.
- Berger BA, Stolz U, Colvin J, Otten EJ. Epidemiology of cannabidiol related cases reported in the National Poison Data System - 2019-2020. Am J Emerg Med. 2021;48:218-223.
- Gaston TE, Ampah SB, Martina Bebin E, et al. Long-term safety and efficacy of highly purified cannabidiol for treatment refractory epilepsy. Epilepsy Behav. 2021;117:107862.
- Velayudhan L, McGoohan K, Bhattacharyya S. Safety and tolerability of natural and synthetic cannabinoids in adults aged over 50 years: A systematic review and meta-analysis. PLoS Med. 2021;18(3):e1003524.
- Berger M, Li E, Rice S, et al. Cannabidiol for treatment-resistant anxiety disorders in young people: An open-label trial. J Clin Psychiatry 2022;83(5):21m14130.
- Dahlgren MK, Lambros AM, Smith RT, Sagar KA, El-Abboud C, Gruber SA. Clinical and cognitive improvement following full-spectrum, high-cannabidiol treatment for anxiety: open-label data from a two-stage, phase 2 clinical trial. Commun Med (Lond) 2022;2(1):
- Perez-Vilar S, Karami S, Long K, Leishear K. Cannabidiol exposures in the United States, National Poison Data System, July 2014-June 2021. Clin Toxicol (Phila) 2022.
- Zubcevic K, Petersen M, Bach FW, et al. Oral capsules of tetra-hydro-cannabinol (THC), cannabidiol (CBD) and their combination in peripheral neuropathic pain treatment. Eur J Pain 2022.
- Ammendolia I, Mannucci C, Cardia L, et al. Pharmacovigilance on cannabidiol as an antiepileptic agent. Front Pharmacol 2023;14:1091978.
- Georgieva D, Langley J, Hartkopf K, et al. Real-world, long-term evaluation of the tolerability and therapy retention of Epidiolex® (cannabidiol) in patients with refractory epilepsy. Epilepsy Behav 2023;141:109159.
- Devinsky O, Cross JH, Laux L, et al. Trial of cannabidiol for drug-resistant seizures in the Dravet Syndrome. N Engl J Med. 2017 May 25;376(21):2011-2020.
- Hess EJ, Moody KA, Geffrey AL, et al. Cannabidiol as a new treatment for drug-resistant epilepsy in tuberous sclerosis complex. Epilepsia. 2016 Oct;57(10):1617-24.
- Devinsky O, Marsh E, Friedman D, et la. Cannabidiol in patients with treatment-resistant epilepsy: an open-label interventional trial. Lancet Neurol. 2016 Mar;15(3):270-8.
- Kaplan EH, Offermann EA, Sievers JW, Comi AM. Cannabidiol treatment for refractory seizures in Sturge-Weber Syndrome. Pediatr Neurol. 2017 Jun;71:18-23.e2.
- Devinsky O, Patel AD, Cross JH, et al. Effect of Cannabidiol on Drop Seizures in the Lennox-Gastaut Syndrome. N Engl J Med. 2018 May 17;378(20):1888-1897.
- Patel AD, Mazurkiewicz-Beldzinska M, Chin RF, et al. Long-term safety and efficacy of add-on cannabidiol in patients with Lennox-Gastaut syndrome: Results of a long-term open-label extension trial. Epilepsia 2021;62(9):2228-2239.
- Consroe P, Sandyk R, Snider SR. Open label evaluation of cannabidiol in dystonic movement disorders. Int J Neurosci 1986;30(4):277-82.
- Bass J, Linz DR. A Case of Toxicity from Cannabidiol Gummy Ingestion. Cureus. 2020;12(4):e7688.
- Davis BH, Beasley TM, Amaral M, et al. Pharmacogenetic Predictors of Cannabidiol Response and Tolerability in Treatment-Resistant Epilepsy. Clin Pharmacol Ther 2021;110(5):1368-1380.
- Martin RC, Gaston TE, Thompson M, et al. Cognitive functioning following long-term cannabidiol use in adults with treatment-resistant epilepsy. Epilepsy Behav. 2019;97:105-110.
- Rog, D. J., Nurmikko, T. J., Friede, T., and Young, C. A. Randomized, controlled trial of cannabis-based medicine in central pain in multiple sclerosis. Neurology 9-27-2005;65(6):812-819.
- Perras, C. Sativex for the management of multiple sclerosis symptoms. Issues Emerg.Health Technol. 2005;(72):1-4.
- Rog, D. J., Nurmikko, T. J., and Young, C. A. Oromucosal delta9-tetrahydrocannabinol/cannabidiol for neuropathic pain associated with multiple sclerosis: an uncontrolled, open-label, 2-year extension trial. Clin Ther. 2007;29(9):2068-2079.
- Lynch, M. E. and Campbell, F. Cannabinoids for treatment of chronic non-cancer pain; a systematic review of randomized trials. Br.J.Clin.Pharmacol. 2011;72(5):735-744.
- Richards, B. L., Whittle, S. L., and Buchbinder, R. Neuromodulators for pain management in rheumatoid arthritis. Cochrane.Database.Syst.Rev. 2012;1:CD008921.
- Duran M, Pérez E, Abanades S, et al. Preliminary efficacy and safety of an oromucosal standardized cannabis extract in chemotherapy-induced nausea and vomiting. Br J Clin Pharmacol. 2010;70(5):656-63.
- Zamarripa CA, Spindle TR, Surujunarain R, et al. Assessment of orally administered ?9-tetrahydrocannabinol when coadministered with cannabidiol on ?9-tetrahydrocannabinol pharmacokinetics and pharmacodynamics in healthy adults: A randomized clinical trial
- Taylor L, Crockett J, Tayo B, Checketts D, Sommerville K. Abrupt withdrawal of cannabidiol (CBD): A randomized trial. Epilepsy Behav. 2020;104(Pt A):106938.
- Arkell TR, Vinckenbosch F, Kevin RC, Theunissen EL, McGregor IS, Ramaekers JG. Effect of Cannabidiol and ?9-Tetrahydrocannabinol on Driving Performance: A Randomized Clinical Trial. JAMA. 2020;324(21):2177-2186.
- McCartney D, Suraev AS, Doohan PT, et al. Effects of cannabidiol on simulated driving and cognitive performance: A dose-ranging randomised controlled trial. J Psychopharmacol 2022.
- Cole TB, Saitz R. Cannabis and Impaired Driving. JAMA. 2020;324(21):2163-2164.
Constipation Gastrointestinal
Orally, cannabidiol has caused dry mouth in some patients in clinical research. In children and adults, cannabidiol oil has caused mild to moderate diarrhea, decreased appetite, weight loss, nausea, and vomiting. Diarrhea, decreased appetite, and weight loss or weight gain have been reported at a higher frequency with doses greater than 15-20 mg/kg daily. In one case, persistent diarrhea and eosinophilic esophagitis due to cannabidiol oil were resolved with dose reduction from 20 mg/kg/day to 15 mg/kg/day in a 13-year-old female with epilepsy. Weight loss also seems to be more prevalent with long-term cannabidiol use. Other adverse effects like diarrhea and vomiting also seem to be more prevalent during long-term (42-96 weeks) cannabidiol treatment when compared with short-term (about 12-14 weeks). Pharmacogenetic variation has also been shown to affect susceptibility to cannabidiol-associated diarrhea. In a 75-year-old female, chronic cannabidiol use for one year was associated with microscopic colitis. Colitis resolved when cannabidiol was discontinued, and recurred after a re-challenge. A systematic review of randomized controlled trials shows that gastrointestinal symptoms, including diarrhea, nausea, vomiting, abdominal pain, abdominal distention, and constipation, make up approximately 60% of all adverse effects related to oral cannabidiol use. About 17% of patients report loss of appetite. However, other rare gastrointestinal events are reported. One case reports cannabinoid hyperemesis syndrome that resolved completely 2 months after cessation in a teenaged male taking cannabidiol 15 mg/kg/day chronically.
Cannabis oromucosal spray that contains cannabidiol 2.5 mg and delta-9-tetrahydrocannabinol (THC) 2.7 mg per actuation (Sativex, GW Pharmaceuticals) can cause dizziness, dry mouth, nausea, and bad taste. Less commonly, this product may cause red and white buccal mucosal patches to develop inside the mouth.
- Consroe P, Sandyk R, Snider SR. Open label evaluation of cannabidiol in dystonic movement disorders. Int J Neurosci 1986;30(4):277-82.
- Velayudhan L, McGoohan K, Bhattacharyya S. Safety and tolerability of natural and synthetic cannabinoids in adults aged over 50 years: A systematic review and meta-analysis. PLoS Med. 2021;18(3):e1003524.
- Berger M, Li E, Rice S, et al. Cannabidiol for treatment-resistant anxiety disorders in young people: An open-label trial. J Clin Psychiatry 2022;83(5):21m14130.
- Dahlgren MK, Lambros AM, Smith RT, Sagar KA, El-Abboud C, Gruber SA. Clinical and cognitive improvement following full-spectrum, high-cannabidiol treatment for anxiety: open-label data from a two-stage, phase 2 clinical trial. Commun Med (Lond) 2022;2(1):
- Zubcevic K, Petersen M, Bach FW, et al. Oral capsules of tetra-hydro-cannabinol (THC), cannabidiol (CBD) and their combination in peripheral neuropathic pain treatment. Eur J Pain 2022.
- Devinsky O, Cross JH, Laux L, et al. Trial of cannabidiol for drug-resistant seizures in the Dravet Syndrome. N Engl J Med. 2017 May 25;376(21):2011-2020.
- Hess EJ, Moody KA, Geffrey AL, et al. Cannabidiol as a new treatment for drug-resistant epilepsy in tuberous sclerosis complex. Epilepsia. 2016 Oct;57(10):1617-24.
- 97021 Jadoon KA, Ratcliffe SH, Barrett DA, et al. Efficacy and safety of cannabidiol and tetrahydrocannabivarin on glycemic and lipid parameters in patients with type 2 diabetes: a randomized, double-blind, placebo-controlled, parallel group pilot study.
- Devinsky O, Marsh E, Friedman D, et la. Cannabidiol in patients with treatment-resistant epilepsy: an open-label interventional trial. Lancet Neurol. 2016 Mar;15(3):270-8.
- Kaplan EH, Offermann EA, Sievers JW, Comi AM. Cannabidiol treatment for refractory seizures in Sturge-Weber Syndrome. Pediatr Neurol. 2017 Jun;71:18-23.e2.
- Devinsky O, Patel AD, Cross JH, et al. Effect of Cannabidiol on Drop Seizures in the Lennox-Gastaut Syndrome. N Engl J Med. 2018 May 17;378(20):1888-1897.
- Thiele EA, Marsh ED, French JA, et al. Cannabidiol in patients with seizures associated with Lennox-Gastaut syndrome (GWPCARE4): a randomised, double-blind, placebo-controlled phase 3 trial. Lancet. 2018 Mar 17;391(10125):1085-1096.
- Klotz KA, Grob D, Hirsch M, Metternich B, Schulze-Bonhage A, Jacobs J. Efficacy and Tolerance of Synthetic Cannabidiol for Treatment of Drug Resistant Epilepsy. Front Neurol. 2019 Dec 10;10:1313.
- Chesney E, Oliver D, Green A, et al. Adverse effects of cannabidiol: a systematic review and meta-analysis of randomized clinical trials. Neuropsychopharmacology. 2020.
- Taylor L, Crockett J, Tayo B, Checketts D, Sommerville K. Abrupt withdrawal of cannabidiol (CBD): A randomized trial. Epilepsy Behav. 2020;104(Pt A):106938.
- Leehey MA, Liu Y, Hart F, et al. Safety and Tolerability of Cannabidiol in Parkinson Disease: An Open Label, Dose-Escalation Study. Cannabis Cannabinoid Res. 2020;5(4):326-336.
- Berger BA, Stolz U, Colvin J, Otten EJ. Epidemiology of cannabidiol related cases reported in the National Poison Data System - 2019-2020. Am J Emerg Med. 2021;48:218-223.
- Gaston TE, Ampah SB, Martina Bebin E, et al. Long-term safety and efficacy of highly purified cannabidiol for treatment refractory epilepsy. Epilepsy Behav. 2021;117:107862.
- Patel AD, Mazurkiewicz-Beldzinska M, Chin RF, et al. Long-term safety and efficacy of add-on cannabidiol in patients with Lennox-Gastaut syndrome: Results of a long-term open-label extension trial. Epilepsia 2021;62(9):2228-2239.
- Scheffer IE, Halford JJ, Miller I, et al. Add-on cannabidiol in patients with Dravet syndrome: Results of a long-term open-label extension trial. Epilepsia 2021;62(10):2505-2517.
- Thiele EA, Bebin EM, Filloux F, et al. Long-term cannabidiol treatment for seizures in patients with tuberous sclerosis complex: An open-label extension trial. Epilepsia 2021.
- Atieh J, Maselli D, Breen-Lyles M, et al. Cannabidiol for functional dyspepsia with normal gastric emptying: A randomized controlled trial. Am J Gastroenterol 2022;117(8):1296-1304.
- Perez-Vilar S, Karami S, Long K, Leishear K. Cannabidiol exposures in the United States, National Poison Data System, July 2014-June 2021. Clin Toxicol (Phila) 2022.
- Patel M, Middleton JP, Goodkin HP, Barnes B, McGowan E, Eid R. Persistent Diarrhea and Eosinophilic Esophagitis Resulting From Chronic Cannabidiol Usage for Refractory Epilepsy. JPGN Rep 2022;3(4):e253.
- de Carvalho Reis R, Almeida KJ, da Silva Lopes L, de Melo Mendes CM, Bor-Seng-Shu E. Efficacy and adverse event profile of cannabidiol and medicinal cannabis for treatment-resistant epilepsy: Systematic review and meta-analysis. Epilepsy Behav. 2020;102:1
- Davis BH, Beasley TM, Amaral M, et al. Pharmacogenetic Predictors of Cannabidiol Response and Tolerability in Treatment-Resistant Epilepsy. Clin Pharmacol Ther 2021;110(5):1368-1380.
- Oruganti P, Betcher S, Wakade Z, Ding X, Abegunde AT. Cannabidiol Oil-Associated Microscopic Colitis. Cureus. 2020;12(9):e10528.
- Souza JDR, Pacheco JC, Rossi GN, et al. Adverse Effects of Oral Cannabidiol: An Updated Systematic Review of Randomized Controlled Trials (2020-2022). Pharmaceutics 2022;14(12):2598.
- Katz DT, Fifi A, Milesi-Halle A, Saps M. A Rare Case of Cannabinoid Hyperemesis Syndrome Secondary to Cannabidiol for Refractory Epilepsy. JPGN Rep 2023;4(1):e280.
- Rog, D. J., Nurmikko, T. J., Friede, T., and Young, C. A. Randomized, controlled trial of cannabis-based medicine in central pain in multiple sclerosis. Neurology 9-27-2005;65(6):812-819.
- Perras, C. Sativex for the management of multiple sclerosis symptoms. Issues Emerg.Health Technol. 2005;(72):1-4.
- Rog, D. J., Nurmikko, T. J., and Young, C. A. Oromucosal delta9-tetrahydrocannabinol/cannabidiol for neuropathic pain associated with multiple sclerosis: an uncontrolled, open-label, 2-year extension trial. Clin Ther. 2007;29(9):2068-2079.
- Lynch, M. E. and Campbell, F. Cannabinoids for treatment of chronic non-cancer pain; a systematic review of randomized trials. Br.J.Clin.Pharmacol. 2011;72(5):735-744.
- Richards, B. L., Whittle, S. L., and Buchbinder, R. Neuromodulators for pain management in rheumatoid arthritis. Cochrane.Database.Syst.Rev. 2012;1:CD008921.
- Busse JW, Vankrunkelsven P, Zeng L, et al. Medical cannabis or cannabinoids for chronic pain: a clinical practice guideline. BMJ 2021;374:n2040.
Epilepsy Dermatologic
Orally, cannabidiol might cause rare skin reactions. In a clinical study in healthy adults, 2 cases of skin reactions, one severe and one mild, were reported. These and 2 additional cases were reported in a follow-up publication specific to cannabidiol-induced skin rash. The rash occurred in 4 female patients after taking oral cannabidiol 300 mg daily for up to 9 days. The earliest case started 6 hours after initial use; all rashes resolved within 5-11 days of treatment discontinuation. The cannabidiol was 99.6% pure (PurMed Global; United States) and dissolved in medium chain triglyceride oil. Taking the medium chain triglyceride oil alone did not reproduce symptoms. In one case, the patient required treatment with oral prednisone 0.5 mg/kg daily. A systematic review of randomized controlled trials suggests that rash makes up approximately 6% of all adverse effects related to oral cannabidiol use, and one meta-analysis of 3 clinical trials in patients with epilepsy shows that taking cannabidiol is associated with about a 3-fold relative risk of rash compared with placebo.
Topically, cannabidiol has resulted in pain on application, as well as dryness, rash, and itching.
- Crippa JAS, Zuardi AW, Guimarães FS, et al. Burnout and Distress Prevention With Cannabidiol in Front-line Health Care Workers Dealing With COVID-19 (BONSAI) Trial Investigators. Efficacy and Safety of Cannabidiol Plus Standard Care vs Standard Care Alone
- Souza JDS, Fassoni-Ribeiro M, Batista RM, et al. Case report: Cannabidiol-induced skin rash: A case series and key recommendations. Front Pharmacol 2022;13:881617.
- Souza JDR, Pacheco JC, Rossi GN, et al. Adverse Effects of Oral Cannabidiol: An Updated Systematic Review of Randomized Controlled Trials (2020-2022). Pharmaceutics 2022;14(12):2598.
- Fazlollahi A, Zahmatyar M, ZareDini M, et al. Adverse Events of Cannabidiol Use in Patients With Epilepsy: A Systematic Review and Meta-analysis. JAMA Netw Open 2023;6(4):e239126.
- Berry-Kravis E, Hagerman R, Budimirovic D, et al. A randomized, controlled trial of ZYN002 cannabidiol transdermal gel in children and adolescents with fragile X syndrome (CONNECT-FX). J Neurodev Disord 2022;14(1):56.
Hypertension Cardiovascular
Orally, cannabidiol has been associated with cardiovascular effects in some reports. In one clinical study, some patients experienced hypotension, orthostatic hypotension, and lightheadedness. Also, cannabidiol has also been linked to tachycardia and hypertension. In Poison Control Center reports of up to 5248 oral single-substance exposures to cannabidiol in adults and children, up to 7% of cases involved tachycardia. However, the doses of cannabidiol that precipitated these reports are unclear. Other research suggests that taking cannabidiol orally does not significantly change blood pressure or heart rate when compared with placebo. A case of ventricular bigeminy and a case of circulatory collapse have been considered to be related to treatment with a specific oromucosal spray that contains cannabidiol 2.5 mg and delta-9-tetrahydrocannabinol (THC) 2.7 mg per actuation (Sativex, GW Pharmaceuticals).
- Consroe P, Sandyk R, Snider SR. Open label evaluation of cannabidiol in dystonic movement disorders. Int J Neurosci 1986;30(4):277-82.
- Berger BA, Stolz U, Colvin J, Otten EJ. Epidemiology of cannabidiol related cases reported in the National Poison Data System - 2019-2020. Am J Emerg Med. 2021;48:218-223.
- Perez-Vilar S, Karami S, Long K, Leishear K. Cannabidiol exposures in the United States, National Poison Data System, July 2014-June 2021. Clin Toxicol (Phila) 2022.
- Consroe, P., Laguna, J., Allender, J., Snider, S., Stern, L., Sandyk, R., Kennedy, K., and Schram, K. Controlled clinical trial of cannabidiol in Huntington's disease. Pharmacol Biochem.Behav. 1991;40(3):701-708.
- Bergamaschi MM, Queiroz RH, Chagas MH, et al. Cannabidiol reduces the anxiety induced by simulated public speaking in treatment-naïve social phobia patients. Neuropsychopharmacology 2011;36(6):1219-26.
- Zuardi AW, Cosme RA, Graeff FG, Guimaraes FS. Effects of ipsapirone and cannabidiol on human experimental anxiety. J Psychopharmacol 1993;7(1 Suppl):82-8.
- Rog, D. J., Nurmikko, T. J., Friede, T., and Young, C. A. Randomized, controlled trial of cannabis-based medicine in central pain in multiple sclerosis. Neurology 9-27-2005;65(6):812-819.
- Rog, D. J., Nurmikko, T. J., and Young, C. A. Oromucosal delta9-tetrahydrocannabinol/cannabidiol for neuropathic pain associated with multiple sclerosis: an uncontrolled, open-label, 2-year extension trial. Clin Ther. 2007;29(9):2068-2079.
Myasthenia gravis Hepatic
Orally, cannabidiol oil has been associated with an elevation in liver transaminases and drug-induced liver injury (DILI). A meta-analysis of 12 clinical trials shows that taking cannabidiol daily is associated with approximately 5 times greater odds of DILI and 6 times greater odds of liver enzyme elevations when compared with placebo. However, many patients were on concomitant medications that can also cause liver injury. A systematic review has also found that elevated liver transaminases make up about 13% of adverse effects related to cannabidiol use. In another study, abnormal liver transaminases occurred in 4 of 25 patients after taking cannabidiol up to 20 mg/kg daily for 4 weeks; levels normalized within 4 weeks of study completion. In an observational study, elevated liver function tests occurred in 2.7% of patients who took prescription cannabidiol oil (Epidiolex) and were the reason for discontinuation in 1 of 25 patients. Pharmacogenetic variation has also been shown to affect susceptibility to liver transaminase elevations with cannabidiol use.
Conversely, 2 large observational studies suggest that the prevalence of elevated liver transaminases in those taking cannabidiol for at least 30 days is similar when compared with the general adult population. The mean daily dose of cannabidiol used in these studies was about 50-55 mg, which is much lower than the doses reported in cases of elevated liver transaminases.
The elevation in liver transaminases appears to occur more frequently at higher doses (20-25 mg/kg), in patients with elevated levels at baseline, and in patients already taking valproic acid or clobazam. While most reported elevations have been mild, some patients taking cannabidiol oil alone or with valproic acid have experienced significant elevations which required discontinuation of either valproic acid or cannabidiol.
- Lo LA, Christiansen A, Eadie L, et al. Cannabidiol-associated hepatotoxicity: A systematic review and meta-analysis. J Intern Med 2023;293(6):724-752.
- Souza JDR, Pacheco JC, Rossi GN, et al. Adverse Effects of Oral Cannabidiol: An Updated Systematic Review of Randomized Controlled Trials (2020-2022). Pharmaceutics 2022;14(12):2598.
- Atieh J, Maselli D, Breen-Lyles M, et al. Cannabidiol for functional dyspepsia with normal gastric emptying: A randomized controlled trial. Am J Gastroenterol 2022;117(8):1296-1304.
- Georgieva D, Langley J, Hartkopf K, et al. Real-world, long-term evaluation of the tolerability and therapy retention of Epidiolex® (cannabidiol) in patients with refractory epilepsy. Epilepsy Behav 2023;141:109159.
- Davis BH, Beasley TM, Amaral M, et al. Pharmacogenetic Predictors of Cannabidiol Response and Tolerability in Treatment-Resistant Epilepsy. Clin Pharmacol Ther 2021;110(5):1368-1380.
- Kaufmann R, Aqua K, Lombardo J, Lee M. Observed Impact of Long-term Consumption of Oral Cannabidiol on Liver Function in Healthy Adults. Cannabis Cannabinoid Res 2021.
- Kaufmann R, Harris Bozer A, Jotte ARK, Aqua K. The Effects of Long-Term Self-Dosing of Cannabidiol on Drowsiness, Testosterone Levels, and Liver Function. Med Cannabis Cannabinoids 2023;6(1):32-40.
- Devinsky O, Cross JH, Laux L, et al. Trial of cannabidiol for drug-resistant seizures in the Dravet Syndrome. N Engl J Med. 2017 May 25;376(21):2011-2020.
- Gaston TE, Bebin EM, Cutter GR, Liu Y, Szaflarski JP; UAB CBD Program. Interactions between cannabidiol and commonly used antiepileptic drugs. Epilepsia. 2017 Sep;58(9):1586-92.
- Hess EJ, Moody KA, Geffrey AL, et al. Cannabidiol as a new treatment for drug-resistant epilepsy in tuberous sclerosis complex. Epilepsia. 2016 Oct;57(10):1617-24.
- Devinsky O, Marsh E, Friedman D, et la. Cannabidiol in patients with treatment-resistant epilepsy: an open-label interventional trial. Lancet Neurol. 2016 Mar;15(3):270-8.
- Kaplan EH, Offermann EA, Sievers JW, Comi AM. Cannabidiol treatment for refractory seizures in Sturge-Weber Syndrome. Pediatr Neurol. 2017 Jun;71:18-23.e2.
- Devinsky O, Patel AD, Cross JH, et al. Effect of Cannabidiol on Drop Seizures in the Lennox-Gastaut Syndrome. N Engl J Med. 2018 May 17;378(20):1888-1897.
- Thiele EA, Marsh ED, French JA, et al. Cannabidiol in patients with seizures associated with Lennox-Gastaut syndrome (GWPCARE4): a randomised, double-blind, placebo-controlled phase 3 trial. Lancet. 2018 Mar 17;391(10125):1085-1096.
- Klotz KA, Grob D, Hirsch M, Metternich B, Schulze-Bonhage A, Jacobs J. Efficacy and Tolerance of Synthetic Cannabidiol for Treatment of Drug Resistant Epilepsy. Front Neurol. 2019 Dec 10;10:1313.
- Chesney E, Oliver D, Green A, et al. Adverse effects of cannabidiol: a systematic review and meta-analysis of randomized clinical trials. Neuropsychopharmacology. 2020.
- Leehey MA, Liu Y, Hart F, et al. Safety and Tolerability of Cannabidiol in Parkinson Disease: An Open Label, Dose-Escalation Study. Cannabis Cannabinoid Res. 2020;5(4):326-336.
- Watkins PB, Church RJ, Li J, Knappertz V. Cannabidiol and Abnormal Liver Chemistries in Healthy Adults: Results of a Phase I Clinical Trial. Clin Pharmacol Ther. 2020.
- Patel AD, Mazurkiewicz-Beldzinska M, Chin RF, et al. Long-term safety and efficacy of add-on cannabidiol in patients with Lennox-Gastaut syndrome: Results of a long-term open-label extension trial. Epilepsia 2021;62(9):2228-2239.
- Scheffer IE, Halford JJ, Miller I, et al. Add-on cannabidiol in patients with Dravet syndrome: Results of a long-term open-label extension trial. Epilepsia 2021;62(10):2505-2517.
- Thiele EA, Bebin EM, Filloux F, et al. Long-term cannabidiol treatment for seizures in patients with tuberous sclerosis complex: An open-label extension trial. Epilepsia 2021.
- Ammendolia I, Mannucci C, Cardia L, et al. Pharmacovigilance on cannabidiol as an antiepileptic agent. Front Pharmacol 2023;14:1091978.
Myasthenia gravis Other
There is some concern that cannabidiol could be used as a substance of abuse. Cannabidiol derived from marijuana is classified as a Schedule I controlled substance by the United States Drug Enforcement Administration (DEA). Epidiolex, an approved prescription formulation of cannabidiol, is classified as a schedule V controlled substance. In a clinical study of healthy recreational polydrug abusers, a single dose of cannabidiol 750 mg was rated no differently than placebo for drug-liking, likelihood of repeat use, or the occurrence of positive effects, such as feeling high or feeling stoned. However, a single dose of cannabidiol 1500 mg or 4500 mg scored higher for likelihood of repeat use and occurrence of positive effects when compared with placebo, although these ratings were lower than those for dronabinol and alprazolam.
- Drug Enforcement Administration, Department of Justice. Schedules of Controlled Substances: Placement in Schedule V of Certain FDA-Approved Drugs Containing Cannabidiol; Corresponding Change to Permit Requirements. Final order. Fed Regist. 2018 Sep 28;83(
- Schoedel KA, Szeto I, Setnik B, et al. Abuse potential assessment of cannabidiol (CBD) in recreational polydrug users: A randomized, double-blind, controlled trial. Epilepsy Behav. 2018 Nov;88:162-171. doi: 10.1016/j.yebeh.2018.07.027. Epub 2018 Oct 2.
Pain Ocular/Otic
Ocular pain and irritation and mydriasis related to oral cannabidiol exposures have been reported in a Poison Control Center report.
Adverse-effects data: Natural Medicines, Therapeutic Research Center
Dosing
There is no single standard dose of CBD for general supplement use. The right amount can depend on the product, the reason for use, and the person. Because of this, it is best to follow the directions on the product label and start with a low amount.
The only well-established dosing comes from the prescription CBD medicine used for seizures, which is carefully dosed by a doctor based on body weight. This is not the same as taking an over-the-counter supplement.
Before starting CBD, talk with your pharmacist or doctor. They can help you decide whether it is appropriate for you and review your other medicines for possible problems.
Cannabidiol (cbd) & Pregnancy
Cannabidiol (cbd) & Breastfeeding
© 2026 Therapeutic Research Center
Pregnancy & lactation ratings: Natural Medicines, Therapeutic Research Center
References & further reading
The 93 references that drive our Cannabidiol (cbd) monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.
- Rog, D. J., Nurmikko, T. J., Friede, T., and Young, C. A. Randomized, controlled trial of cannabis-based medicine in central pain in multiple sclerosis. Neurology 9-27-2005;65(6):812-819. PubMed
- Perras, C. Sativex for the management of multiple sclerosis symptoms. Issues Emerg.Health Technol. 2005;(72):1-4.
- Rog, D. J., Nurmikko, T. J., and Young, C. A. Oromucosal delta9-tetrahydrocannabinol/cannabidiol for neuropathic pain associated with multiple sclerosis: an uncontrolled, open-label, 2-year extension trial. Clin Ther. 2007;29(9):2068-2079.
- Consroe, P., Laguna, J., Allender, J., Snider, S., Stern, L., Sandyk, R., Kennedy, K., and Schram, K. Controlled clinical trial of cannabidiol in Huntington's disease. Pharmacol Biochem.Behav. 1991;40(3):701-708. PubMed
- Lynch, M. E. and Campbell, F. Cannabinoids for treatment of chronic non-cancer pain; a systematic review of randomized trials. Br.J.Clin.Pharmacol. 2011;72(5):735-744. PubMed
- Richards, B. L., Whittle, S. L., and Buchbinder, R. Neuromodulators for pain management in rheumatoid arthritis. Cochrane.Database.Syst.Rev. 2012;1:CD008921. PubMed
- Carlini EA, Cunha JM. Hypnotic and antiepileptic effects of cannabidiol. J Clin Pharmacol 1981;21(8-9 Suppl):417S-27S. PubMed
- Bergamaschi MM, Queiroz RH, Chagas MH, et al. Cannabidiol reduces the anxiety induced by simulated public speaking in treatment-naïve social phobia patients. Neuropsychopharmacology 2011;36(6):1219-26. PubMed
- Yamaori S, Kushihara M, Yamamoto I, Watanabe K. Characterization of major phytocannabinoids, cannabidiol and cannabinol, as isoform-selective potent inhibitors of human CYP1 enzymes. Biochem Pharmacol 2010;79(11):1691-8.
- Yamaori S, Maeda C, Yamamoto I, Watanabe K. Differential inhibition of human cytochrome P450 2A6 and 2B6 by major phytocannabinoids. Forensic Toxicol 2011;29:117-24. DOI
- Yamaori S, Okamoto Y, Yamamoto I, Watanabe K. Cannabidiol, a major phytocannabinoid, as a potent atypical inhibitor for CYP2D6. Drug Metab Dispos 2011;39(11):2049-56. PubMed
- Yamaori S, Ebisawa J, Okushima Y, et al. Potent inhibition of human cytochrome P450 3A isoforms by cannabidiol: role of phenolic hydroxyl groups in the resorcinol moiety. Life Sci 2011;88(15-16):730-6. PubMed
- Harvey DJ. Absorption, distribution, and biotransformation of the cannabinoids. Marijuana and Medicine. 1999;91-103. DOI
- Bornheim LM, Everhart ET, Li J, Correia MA. Characterization of cannabidiol-mediated cytochrome P450 inactivation. Biochem Pharmacol 1993;45(6):1323-31. PubMed
- Consroe P, Sandyk R, Snider SR. Open label evaluation of cannabidiol in dystonic movement disorders. Int J Neurosci 1986;30(4):277-82. PubMed
- Zuardi AW, Cosme RA, Graeff FG, Guimaraes FS. Effects of ipsapirone and cannabidiol on human experimental anxiety. J Psychopharmacol 1993;7(1 Suppl):82-8. PubMed
- Monti JM. Hypnoticlike effects of cannabidiol in the rat. Psychopharmacology (Berl) 1977;55(3):263-5. PubMed
- Pickens JT. Sedative activity of cannabis in relation to its delta'-trans-tetrahydrocannabinol and cannabidiol content. Br J Pharmacol 1981;72(4):649-56.
- Duran M, Pérez E, Abanades S, et al. Preliminary efficacy and safety of an oromucosal standardized cannabis extract in chemotherapy-induced nausea and vomiting. Br J Clin Pharmacol. 2010;70(5):656-63. PubMed
- Devinsky O, Cross JH, Laux L, et al. Trial of cannabidiol for drug-resistant seizures in the Dravet Syndrome. N Engl J Med. 2017 May 25;376(21):2011-2020. PubMed
- Gaston TE, Bebin EM, Cutter GR, Liu Y, Szaflarski JP; UAB CBD Program. Interactions between cannabidiol and commonly used antiepileptic drugs. Epilepsia. 2017 Sep;58(9):1586-92. PubMed
- Hess EJ, Moody KA, Geffrey AL, et al. Cannabidiol as a new treatment for drug-resistant epilepsy in tuberous sclerosis complex. Epilepsia. 2016 Oct;57(10):1617-24. PubMed
- 97021 Jadoon KA, Ratcliffe SH, Barrett DA, et al. Efficacy and safety of cannabidiol and tetrahydrocannabivarin on glycemic and lipid parameters in patients with type 2 diabetes: a randomized, double-blind, placebo-controlled, parallel group pilot study. PubMed
- Devinsky O, Marsh E, Friedman D, et la. Cannabidiol in patients with treatment-resistant epilepsy: an open-label interventional trial. Lancet Neurol. 2016 Mar;15(3):270-8.
- Geffrey AL, Pollack SF, Bruno PL, Thiele EA. Drug-drug interaction between clobazam and cannabidiol in children with refractory epilepsy. Epilepsia. 2015 Aug;56(8):1246-51. PubMed
- Kaplan EH, Offermann EA, Sievers JW, Comi AM. Cannabidiol treatment for refractory seizures in Sturge-Weber Syndrome. Pediatr Neurol. 2017 Jun;71:18-23.e2. PubMed
- Devinsky O, Patel AD, Cross JH, et al. Effect of Cannabidiol on Drop Seizures in the Lennox-Gastaut Syndrome. N Engl J Med. 2018 May 17;378(20):1888-1897. PubMed
- Thiele EA, Marsh ED, French JA, et al. Cannabidiol in patients with seizures associated with Lennox-Gastaut syndrome (GWPCARE4): a randomised, double-blind, placebo-controlled phase 3 trial. Lancet. 2018 Mar 17;391(10125):1085-1096.
- Schoedel KA, Szeto I, Setnik B, et al. Abuse potential assessment of cannabidiol (CBD) in recreational polydrug users: A randomized, double-blind, controlled trial. Epilepsy Behav. 2018 Nov;88:162-171. doi: 10.1016/j.yebeh.2018.07.027. Epub 2018 Oct 2. PubMed
- Drug Enforcement Administration, Department of Justice. Schedules of Controlled Substances: Placement in Schedule V of Certain FDA-Approved Drugs Containing Cannabidiol; Corresponding Change to Permit Requirements. Final order. Fed Regist. 2018 Sep 28;83(
- Epidiolex (cannabidiol) prescribing information. Greenwich Biosciences, Inc., Carlsbad, CA, 2019. Available at: https://www.epidiolex.com/sites/default/files/EPIDIOLEX_Full_Prescribing_Information.pdf (accessed 5/9/2019)
- Product information for Marinol. AbbVie. North Chicago, IL 60064. August 2017. Available at: https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/018651s029lbl.pdf.
- Klotz KA, Hirsch M, Heers M, Schulze-Bonhage A, Jacobs J. Effects of cannabidiol on brivaracetam plasma levels. Epilepsia. 2019;60(7):e74-e77. PubMed
- Laux LC, Bebin EM, Checketts D, et al. Long-term safety and efficacy of cannabidiol in children and adults with treatment resistant Lennox-Gastaut syndrome or Dravet syndrome: Expanded access program results. Epilepsy Res. 2019;154:13-20. PubMed
- Leino AD, Emoto C, Fukuda T, Privitera M, Vinks AA, Alloway RR. Evidence of a clinically significant drug-drug interaction between cannabidiol and tacrolimus. Am J Transplant. 2019;19(10):2944-2948. PubMed
- Martin RC, Gaston TE, Thompson M, et al. Cognitive functioning following long-term cannabidiol use in adults with treatment-resistant epilepsy. Epilepsy Behav. 2019;97:105-110. PubMed
- FDA Consumer Updates: What You Should Know About Using Cannabis, Including CBD, When Pregnant or Breastfeeding. U. S. Food and Drug Administration (FDA). October 2019. Available at: https://www.fda.gov/consumers/consumer-updates/what-you-should-know-about
- Wiemer-Kruel A, Stiller B, Bast T. Cannabidiol Interacts Significantly with Everolimus-Report of a Patient with Tuberous Sclerosis Complex. Neuropediatrics. 2019. PubMed
- Klotz KA, Grob D, Hirsch M, Metternich B, Schulze-Bonhage A, Jacobs J. Efficacy and Tolerance of Synthetic Cannabidiol for Treatment of Drug Resistant Epilepsy. Front Neurol. 2019 Dec 10;10:1313. PubMed
- Madden K, Tanco K, Bruera E. Clinically Significant Drug-Drug Interaction Between Methadone and Cannabidiol. Pediatrics. 2020;e20193256. PubMed
- Bass J, Linz DR. A Case of Toxicity from Cannabidiol Gummy Ingestion. Cureus. 2020;12(4):e7688. PubMed
- Ben-Menachem E, Gunning B, Arenas Cabrera CM, et al. A Phase II Randomized Trial to Explore the Potential for Pharmacokinetic Drug-Drug Interactions with Stiripentol or Valproate when Combined with Cannabidiol in Patients with Epilepsy. CNS Drugs. 2020;34 PubMed
- Chesney E, Oliver D, Green A, et al. Adverse effects of cannabidiol: a systematic review and meta-analysis of randomized clinical trials. Neuropsychopharmacology. 2020. PubMed
- Darweesh RS, Khamis TN, El-Elimat T. The effect of cannabidiol on the pharmacokinetics of carbamazepine in rats. Naunyn Schmiedebergs Arch Pharmacol. 2020. PubMed
- de Carvalho Reis R, Almeida KJ, da Silva Lopes L, de Melo Mendes CM, Bor-Seng-Shu E. Efficacy and adverse event profile of cannabidiol and medicinal cannabis for treatment-resistant epilepsy: Systematic review and meta-analysis. Epilepsy Behav. 2020;102:1 PubMed
- Ebrahimi-Fakhari D, Agricola KD, Tudor C, Krueger D, Franz DN. Cannabidiol Elevates Mechanistic Target of Rapamycin Inhibitor Levels in Patients With Tuberous Sclerosis Complex. Pediatr Neurol. 2020;105:59-61. PubMed
- Morrison G, Crockett J, Blakey G, Sommerville K. A Phase 1, Open-Label, Pharmacokinetic Trial to Investigate Possible Drug-Drug Interactions Between Clobazam, Stiripentol, or Valproate and Cannabidiol in Healthy Subjects. Clin Pharmacol Drug Dev. 2019;8(8 PubMed
- McNamara NA, Dang LT, Sturza J, et al. Thrombocytopenia in pediatric patients on concurrent cannabidiol and valproic acid. Epilepsia. 2020. PubMed
- Taylor L, Crockett J, Tayo B, Checketts D, Sommerville K. Abrupt withdrawal of cannabidiol (CBD): A randomized trial. Epilepsy Behav. 2020;104(Pt A):106938. PubMed
- Cortopassi J. Warfarin dose adjustment required after cannabidiol initiation and titration. Am J Health Syst Pharm. 2020;77(22):1846-1851. PubMed
- Singh RK, Dillon B, Tatum DA, Van Poppel KC, Bonthius DJ. Drug-Drug Interactions Between Cannabidiol and Lithium. Child Neurol Open. 2020;7:2329048X20947896. PubMed
- Arkell TR, Vinckenbosch F, Kevin RC, Theunissen EL, McGregor IS, Ramaekers JG. Effect of Cannabidiol and ?9-Tetrahydrocannabinol on Driving Performance: A Randomized Clinical Trial. JAMA. 2020;324(21):2177-2186.
- Cole TB, Saitz R. Cannabis and Impaired Driving. JAMA. 2020;324(21):2163-2164. PubMed
- Leehey MA, Liu Y, Hart F, et al. Safety and Tolerability of Cannabidiol in Parkinson Disease: An Open Label, Dose-Escalation Study. Cannabis Cannabinoid Res. 2020;5(4):326-336. PubMed
- Oruganti P, Betcher S, Wakade Z, Ding X, Abegunde AT. Cannabidiol Oil-Associated Microscopic Colitis. Cureus. 2020;12(9):e10528. PubMed
- Parihar V, Rogers A, Blain AM, Zacharias SRK, Patterson LL, Siyam MA. Reduction in Tamoxifen Metabolites Endoxifen and N-desmethyltamoxifen With Chronic Administration of Low Dose Cannabidiol: A CYP3A4 and CYP2D6 Drug Interaction. J Pharm Pract. 2020:8971 PubMed
- Watkins PB, Church RJ, Li J, Knappertz V. Cannabidiol and Abnormal Liver Chemistries in Healthy Adults: Results of a Phase I Clinical Trial. Clin Pharmacol Ther. 2020. PubMed
- Anderson LL, Doohan PT, Oldfield L, et al. Citalopram and Cannabidiol: In Vitro and In Vivo Evidence of Pharmacokinetic Interactions Relevant to the Treatment of Anxiety Disorders in Young People. J Clin Psychopharmacol. 2021. PubMed
- Berger BA, Stolz U, Colvin J, Otten EJ. Epidemiology of cannabidiol related cases reported in the National Poison Data System - 2019-2020. Am J Emerg Med. 2021;48:218-223. PubMed
- Gaston TE, Ampah SB, Martina Bebin E, et al. Long-term safety and efficacy of highly purified cannabidiol for treatment refractory epilepsy. Epilepsy Behav. 2021;117:107862. PubMed
- Thai C, Tayo B, Critchley D. A Phase 1 Open-Label, Fixed-Sequence Pharmacokinetic Drug Interaction Trial to Investigate the Effect of Cannabidiol on the CYP1A2 Probe Caffeine in Healthy Subjects. Clin Pharmacol Drug Dev. 2021. PubMed
- Velayudhan L, McGoohan K, Bhattacharyya S. Safety and tolerability of natural and synthetic cannabinoids in adults aged over 50 years: A systematic review and meta-analysis. PLoS Med. 2021;18(3):e1003524. PubMed
- Crippa JAS, Zuardi AW, Guimarães FS, et al. Burnout and Distress Prevention With Cannabidiol in Front-line Health Care Workers Dealing With COVID-19 (BONSAI) Trial Investigators. Efficacy and Safety of Cannabidiol Plus Standard Care vs Standard Care Alone
- Patel AD, Mazurkiewicz-Beldzinska M, Chin RF, et al. Long-term safety and efficacy of add-on cannabidiol in patients with Lennox-Gastaut syndrome: Results of a long-term open-label extension trial. Epilepsia 2021;62(9):2228-2239. PubMed
- Scheffer IE, Halford JJ, Miller I, et al. Add-on cannabidiol in patients with Dravet syndrome: Results of a long-term open-label extension trial. Epilepsia 2021;62(10):2505-2517. PubMed
- Davis BH, Beasley TM, Amaral M, et al. Pharmacogenetic Predictors of Cannabidiol Response and Tolerability in Treatment-Resistant Epilepsy. Clin Pharmacol Ther 2021;110(5):1368-1380. PubMed
- Nasrin S, Watson CJW, Perez-Paramo YX, Lazarus P. Cannabinoid Metabolites as Inhibitors of Major Hepatic CYP450 Enzymes, with Implications for Cannabis-Drug Interactions. Drug Metab Dispos 2021;49(12):1070-1080. PubMed
- Thiele EA, Bebin EM, Filloux F, et al. Long-term cannabidiol treatment for seizures in patients with tuberous sclerosis complex: An open-label extension trial. Epilepsia 2021. PubMed
- Kaufmann R, Aqua K, Lombardo J, Lee M. Observed Impact of Long-term Consumption of Oral Cannabidiol on Liver Function in Healthy Adults. Cannabis Cannabinoid Res 2021. PubMed
- Busse JW, Vankrunkelsven P, Zeng L, et al. Medical cannabis or cannabinoids for chronic pain: a clinical practice guideline. BMJ 2021;374:n2040. PubMed
- Gardener H, Wallin C, Bowen J. Heavy metal and phthalate contamination and labeling integrity in a large sample of US commercially available cannabidiol (CBD) products. Sci Total Environ 2022;851(Pt 1):158110. PubMed
- Atieh J, Maselli D, Breen-Lyles M, et al. Cannabidiol for functional dyspepsia with normal gastric emptying: A randomized controlled trial. Am J Gastroenterol 2022;117(8):1296-1304. PubMed
- Berger M, Li E, Rice S, et al. Cannabidiol for treatment-resistant anxiety disorders in young people: An open-label trial. J Clin Psychiatry 2022;83(5):21m14130. PubMed
- Souza JDS, Fassoni-Ribeiro M, Batista RM, et al. Case report: Cannabidiol-induced skin rash: A case series and key recommendations. Front Pharmacol 2022;13:881617. PubMed
- McCartney D, Suraev AS, Doohan PT, et al. Effects of cannabidiol on simulated driving and cognitive performance: A dose-ranging randomised controlled trial. J Psychopharmacol 2022. PubMed
- Anderson LL, Arnold JC, McGregor IS, Nation TR. A potential drug-gene-drug interaction between cannabidiol, CYP2D6*4, and fluoxetine: A case report. J Clin Psychopharmacol 2022;42(4):422-424. PubMed
- Berry-Kravis E, Hagerman R, Budimirovic D, et al. A randomized, controlled trial of ZYN002 cannabidiol transdermal gel in children and adolescents with fragile X syndrome (CONNECT-FX). J Neurodev Disord 2022;14(1):56. PubMed
- Souza JDR, Pacheco JC, Rossi GN, et al. Adverse Effects of Oral Cannabidiol: An Updated Systematic Review of Randomized Controlled Trials (2020-2022). Pharmaceutics 2022;14(12):2598. PubMed
- Dahlgren MK, Lambros AM, Smith RT, Sagar KA, El-Abboud C, Gruber SA. Clinical and cognitive improvement following full-spectrum, high-cannabidiol treatment for anxiety: open-label data from a two-stage, phase 2 clinical trial. Commun Med (Lond) 2022;2(1): PubMed
- Hardy J, Greer R, Huggett G, Kearney A, Gurgenci T, Good P. Phase IIb Randomized, Placebo-Controlled, Dose-Escalating, Double-Blind Study of Cannabidiol Oil for the Relief of Symptoms in Advanced Cancer (MedCan1-CBD). J Clin Oncol 2022. PubMed
- Perez-Vilar S, Karami S, Long K, Leishear K. Cannabidiol exposures in the United States, National Poison Data System, July 2014-June 2021. Clin Toxicol (Phila) 2022. PubMed
- Zubcevic K, Petersen M, Bach FW, et al. Oral capsules of tetra-hydro-cannabinol (THC), cannabidiol (CBD) and their combination in peripheral neuropathic pain treatment. Eur J Pain 2022.
- Zamarripa CA, Spindle TR, Surujunarain R, et al. Assessment of orally administered ?9-tetrahydrocannabinol when coadministered with cannabidiol on ?9-tetrahydrocannabinol pharmacokinetics and pharmacodynamics in healthy adults: A randomized clinical trial PubMed
- Treyer A, Reinhardt JK, Eigenmann DE, Oufir M, Hamburger M. Phytochemical comparison of medicinal cannabis extracts and study of their CYP-mediated interactions with coumarinic oral anticoagulants. Med Cannabis Cannabinoids. 2023;6(1):21-31. PubMed
- Ammendolia I, Mannucci C, Cardia L, et al. Pharmacovigilance on cannabidiol as an antiepileptic agent. Front Pharmacol 2023;14:1091978. PubMed
- Bansal S, Zamarripa CA, Spindle TR, et al. Evaluation of Cytochrome P450-Mediated Cannabinoid-Drug Interactions in Healthy Adult Participants. Clin Pharmacol Ther 2023.
- Fazlollahi A, Zahmatyar M, ZareDini M, et al. Adverse Events of Cannabidiol Use in Patients With Epilepsy: A Systematic Review and Meta-analysis. JAMA Netw Open 2023;6(4):e239126. PubMed
- Georgieva D, Langley J, Hartkopf K, et al. Real-world, long-term evaluation of the tolerability and therapy retention of Epidiolex® (cannabidiol) in patients with refractory epilepsy. Epilepsy Behav 2023;141:109159. PubMed
- Katz DT, Fifi A, Milesi-Halle A, Saps M. A Rare Case of Cannabinoid Hyperemesis Syndrome Secondary to Cannabidiol for Refractory Epilepsy. JPGN Rep 2023;4(1):e280. PubMed
- Kaufmann R, Harris Bozer A, Jotte ARK, Aqua K. The Effects of Long-Term Self-Dosing of Cannabidiol on Drowsiness, Testosterone Levels, and Liver Function. Med Cannabis Cannabinoids 2023;6(1):32-40. PubMed
- Lo LA, Christiansen A, Eadie L, et al. Cannabidiol-associated hepatotoxicity: A systematic review and meta-analysis. J Intern Med 2023;293(6):724-752. PubMed
- Patel M, Middleton JP, Goodkin HP, Barnes B, McGowan E, Eid R. Persistent Diarrhea and Eosinophilic Esophagitis Resulting From Chronic Cannabidiol Usage for Refractory Epilepsy. JPGN Rep 2022;3(4):e253. PubMed
- Wray L, Berwaerts J, Critchley D, et al. Pharmacokinetic Drug-Drug Interaction With Coadministration of Cannabidiol and Everolimus in a Phase 1 Healthy Volunteer Trial. Clin Pharmacol Drug Dev 2023. PubMed
This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.
Parts of this content are provided by the Therapeutic Research Center, LLC.
DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
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Cannabidiol (cbd): Common Questions
What is Cannabidiol (cbd) used for, and does it work?
Does Cannabidiol (cbd) interact with prescription medications?
How are Cannabidiol (cbd) interactions rated?
Is it safe to take Cannabidiol (cbd) with my medications?
Where does this Cannabidiol (cbd) interaction information come from?
Will CBD make me feel high?
What do people use CBD for?
Is CBD safe to take every day?
Can I take CBD while pregnant or breastfeeding?
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