Major interaction on record — check this product against your medications before combining. Based on 8 of 13 ingredients. Check your meds →
Dietary supplement

Intellect Ingredients & Drug Interactions

by 8WeeksOut

Intellect label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Intellect against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Major

Intellect is a dietary supplement by 8WeeksOut with 13 active ingredients. Its ingredients are commonly taken for memory and cognitive support, brain blood flow, stroke recovery.Based on those ingredients, 1,454 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Adrafinil, Bacopa monniera, Dicaffeine Malate. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Intellect by 8WeeksOut

Ask about any prescription or over-the-counter medication and we check it for interactions with Intellect by 8WeeksOut — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Intellect by 8WeeksOut

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 13, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 13 of its 13 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Intellect contains 13 active ingredients targeting cognitive function and mental performance. The formula includes docosahexaenoic acid (an omega-3 fatty acid), vinpocetine (a plant-derived compound), phosphatidylserine and alpha-GPC (both brain-supporting fats), bacopa monniera and huperzine A (herbal extracts), plus caffeine from dicaffeine malate for alertness.

It also contains adrafinil and L-theanine (amino acid derivatives), along with noopept, phenylpiracetam, oxiracetam, and N-acetyl L-tyrosine—compounds with proposed cognitive effects. The capsules are filled with inactive ingredients including gelatine, rice flour, and magnesium stearate.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: optimize brain performance and cognitive function.
  • We looked for evidence on: Age-related cognitive decline, Alzheimer disease, Attention deficit-hyperactivity disorder (ADHD), Cognitive function, Cognitive impairment, Dementia — and 4 related terms.
  • The strongest evidence on file: Caffeine is rated "Likely Effective" for Mental alertness (Natural Medicines).
  • Also on file: Vinpocetine is rated "Possibly Effective" for Dementia.
  • Also on file: Huperzine A is rated "Possibly Effective" for Alzheimer disease.

Evidence for this formula's ingredients is mixed. Vinpocetine is possibly effective for dementia but has insufficient evidence for tinnitus, motion sickness, stroke, and chronic fatigue.

Phosphatidylserine is possibly effective for age-related cognitive decline and Alzheimer disease, but insufficient evidence exists for ADHD, cognitive function, and dementia. Bacopa has insufficient evidence across its tested uses including Alzheimer disease, ADHD, cognitive function, and back pain.

Dicaffeine malate (caffeine) is effective for postoperative headache and neonatal apnea, likely effective for mental alertness and athletic performance, and possibly effective for a breathing condition in newborns. Adrafinil, alpha-GPC, huperzine A, and L-theanine all lack sufficient reliable evidence for most of their proposed uses; L-theanine is possibly effective for cognitive function.

The data we hold does not establish effectiveness for noopept, phenylpiracetam, and oxiracetam.

The evidence, ingredient by ingredient Vinpocetine Phosphatidylserine Bacopa Caffeine Adrafinil Alpha-gpc Theanine Huperzine A

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 8 of the 8 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 8 of 8.
  • General safety write-ups exist for 8 of 8.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most ingredients are generally well tolerated in short-term use, but long-term safety data are limited across the board. Vinpocetine is FDA-warned against in pregnancy and should be avoided while breastfeeding; common side effects include anxiety, dizziness, headache, sleep disturbance, and stomach upset, with rare serious effects like arrhythmias.

Bacopa, phosphatidylserine, adrafinil, alpha-GPC, and huperzine A should all be avoided in pregnancy and breastfeeding due to insufficient safety data. Bacopa causes gastrointestinal upset in 12–30% of users; huperzine A can cause dose-dependent cholinergic side effects (nausea, diarrhea, blurred vision, dizziness).

Adrafinil converts to a stimulant-like drug and may stress the liver. Dicaffeine malate (caffeine) is possibly unsafe in high doses during pregnancy and passes into breast milk; it commonly causes anxiety, insomnia, jitteriness, and stomach upset.

L-theanine and alpha-GPC are rarely associated with headache and insomnia. We hold no safety data for docosahexaenoic acid, noopept, N-acetyl L-tyrosine, phenylpiracetam, or oxiracetam.

Side effects, ingredient by ingredient Vinpocetine Phosphatidylserine Bacopa Caffeine Adrafinil Alpha-gpc Theanine Huperzine A

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 8 of the 8 matched ingredients can interact with medications — Vinpocetine, Bacopa, Huperzine A, Caffeine, Phosphatidylserine, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; lithium.
  • For scale: 1,455 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Check with your doctor or pharmacist before using this product if you take ephedrine (risk of serious stimulant toxicity); modafinil (major interaction with adrafinil); blood thinners or anticoagulants like warfarin (vinpocetine increases bleeding risk); blood pressure medications (adrafinil and L-theanine may reduce effectiveness); anticonvulsants like phenobarbital or carbamazepine (caffeine may reduce effects and raise seizure risk); antipsychotics like clozapine (caffeine increases toxicity); sedatives like pentobarbital (caffeine reduces effect); anticholinergic or cholinergic drugs (bacopa, phosphatidylserine, and huperzine A create conflicting effects); or quinolone antibiotics, cimetidine, and other medications metabolized by CYP1A2, CYP2C9, CYP2C19, or CYP3A4 enzymes (bacopa and adrafinil may alter drug levels).

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

Intellect targets cognitive performance with a broad mix of herbal and synthetic compounds, but the evidence for most ingredients is either limited or conflicting. The serious concern here is the combination of stimulants (caffeine and adrafinil) with multiple enzyme-affecting ingredients—this product requires careful medication review before you start.

Anyone on blood thinners, blood pressure drugs, seizure medications, antipsychotics, anticholinergics, or cholinergic medications, or taking the stimulant prescription drug modafinil, needs to talk with their doctor or pharmacist first.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 8 of 13 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 24, 2020.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Intellect, straight from the product label.

Brand 8WeeksOut
Barcode (UPC) 647732635188
Net contents 180 Capsule(s)
Market status On market
Date entered into DSLD Jun 24, 2020
DSLD ID 228495
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Intellect by 8WeeksOut, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
3 Capsule(s)
Maximum serving Sizes:
3 Capsule(s)
Servings per container
60
UPC/BARCODE
647732635188
IngredientAmount% DV
Docosahexaenoic Acid100 mg--
Vinpocetine30 mg--
Phosphatidylserine150 mg--
Bacopa monniera200 mg--
Dicaffeine Malate60 mg--
Noopept30 mg--
Adrafinil200 mg--
Alpha GPC300 mg--
N Acetyl L Tyrosine250 mg--
Phenylpiracetam125 mg--
Oxiracetam800 mg--
L Theonine250 mg--
Huperzine150 mcg--

Other ingredients: Gelatine Caps, Rice Flour, Magnesium Stearate

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Formula

Actions: A blend of nootropics (neuropeptides) that optimize brain performance.

Formulation

Improves stress response Expand productivity Increase verbal fluency Improve mental endurance Find the right words faster Avoid distractions

Struggle less, accomplish more

Suggested/Recommended/Usage/Directions

Directions: Take 3 caps in the morning with food, then take 3 more caps in the afternoon with food. For maximum effectiveness take no more than 6 capsules a day.

Precautions

Warnings: For adults only.

Consult a physician if pregnant or nursing, taking medications or have a pre-existing medical condition. Individuals taking MAO inhibitors or who suffer compromised mental function should not take Intellect.

May interfere with the effects of alcohol.

Keep out of reach of children.

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

General Statements

100% Money back guarantee

FDA Statement of Identity

Dietary Supplement

Seals/Symbols

ASI Food Safety FDA Registered Facility GMP Good Manufacturing Practice Consistent Quality Made in U.S.A.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Intellect by 8WeeksOut label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Intellect label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Intellect by 8WeeksOut

These are the 13 active ingredients this product is made of. Select any to open its full monograph.

Serving size3 Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Docosahexaenoic Acid

100 mg per serving

Vinpocetine

Interacts with
208 drugs
30 mg per serving

Vinpocetine is a lab-made compound based on a chemical from the periwinkle plant, and it is marketed mainly for memory and brain health. The evidence...

Vinpocetine monograph & interactions

Phosphatidylserine

Interacts with
219 drugs
150 mg per serving

Phosphatidylserine is a natural fat-like compound found in cell membranes, especially in the brain, and it is sold mainly to support memory and thinki...

Phosphatidylserine monograph & interactions

Bacopa monniera

Interacts with
930 drugs
200 mg per serving

Bacopa is an Ayurvedic herb most often used for memory and thinking. Some small studies suggest it may modestly help memory when taken regularly for s...

Bacopa monniera monograph & interactions

Dicaffeine Malate

Interacts with
655 drugs
60 mg per serving

Caffeine is a natural stimulant found in coffee, tea, and many other plants and products. In moderate amounts it can boost alertness and reduce tiredn...

Dicaffeine Malate monograph & interactions

Noopept

30 mg per serving

Adrafinil

Interacts with
1,057 drugs
200 mg per serving

Adrafinil is a synthetic compound that the body converts into modafinil, a prescription wakefulness-promoting drug. It is sometimes sold as a nootropi...

Adrafinil monograph & interactions

Alpha GPC

Interacts with
16 drugs
300 mg per serving

Alpha-GPC is a choline-containing compound used mainly for memory, brain health, and as a choline source. There is some evidence it may help cognition...

Alpha GPC monograph & interactions

N Acetyl L Tyrosine

250 mg per serving

Phenylpiracetam

125 mg per serving

Oxiracetam

800 mg per serving

L Theonine

Interacts with
565 drugs
250 mg per serving

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong dro...

L Theonine monograph & interactions

Huperzine

Interacts with
219 drugs
150 mcg per serving

Huperzine A is a purified compound from a Chinese clubmoss that acts like a mild cholinesterase inhibitor, similar in mechanism to some prescription A...

Huperzine monograph & interactions

Other (inactive) ingredients: Gelatine Caps, Rice Flour, Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Intellect by 8WeeksOut Drug Interactions

Want to check YOUR meds against Intellect?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
1,454Drugs
9 Major 1,253 Moderate 192 Minor

Ingredients driving the most interactions

Adrafinil 1,057
Bacopa monniera 930
Dicaffeine Malate 655
L Theonine 565
Phosphatidylserine 219

Individual Drug Interactions

The ingredients in Intellect interact with 1,454 drugs. Click any drug to see the details.

8 of the 13 ingredients in Intellect interact with drugs. Each result below shows which ingredient is responsible. Adrafinil Bacopa monniera Dicaffeine Malate L Theonine Phosphatidylserine Huperzine Vinpocetine Alpha GPC

Each ingredient & the kinds of drugs it affects

For each ingredient in Intellect with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Adrafinil11 drug types · 1,057 drugs

Modafinil (Provigil)

Concomitant use might increase the risk for serious adverse effects.
Adrafinil is a precursor to the stimulant prescription drug modafinil. Concomitant use with modafinil would be expected to result in increased clinical and adverse effects.

Likelihood Likely Evidence D
Antihypertensive Drugs

Theoretically, adrafinil might reduce the effects of antihypertensive drugs.
Adrafinil is a precursor to the stimulant prescription drug modafinil. Modafinil has been shown to increase diastolic and systolic blood pressure. Retrospective analyses show that patients taking modafinil had a small but increased rate of requiring new antihypertensive drugs or increased use of antihypertensive drugs when compared with placebo.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, adrafinil might reduce the levels and clinical effects of CYP1A2 substrates.
Adrafinil is a precursor to the stimulant prescription drug modafinil. Modafinil has been shown to weakly induce CYP1A2 activity in vitro.

Likelihood Possible Evidence D
Cytochrome P450 2B6 (Cyp2B6) Substrates

Theoretically, adrafinil might reduce the levels and clinical effects of CYP2B6 substrates.
Adrafinil is a precursor to the stimulant prescription drug modafinil. Modafinil has been shown to weakly induce CYP2B6 activity in vitro.

Likelihood Possible Evidence D
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, adrafinil might increase the levels and clinical effects of CYP2C19 substrates.
Adrafinil is a precursor to the stimulant prescription drug modafinil. Modafinil has been shown to inhibit CYP2C19 activity in vitro.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, adrafinil might increase the levels and clinical effects of CYP2C9 substrates.
Adrafinil is a precursor to the stimulant prescription drug modafinil. Modafinil has been shown to reduce CYP2C9 expression in vitro.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Inhibitors

Theoretically, drugs that inhibit CYP3A4 might increase the levels and clinical effects of adrafinil.
Adrafinil is a precursor to the stimulant prescription drug modafinil. Modafinil is metabolized by CYP3A4.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, adrafanil might reduce levels and clinical effects of CYP3A4 substrates.
Adrafinil is a precursor to the stimulant prescription drug modafinil. Modafinil has been shown to weakly induce CYP3A4 activity.

Likelihood Possible Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use might increase the risk for serious adverse effects.
Adrafinil is a precursor to the stimulant prescription drug modafinil. Modafinil, and a related drug, armodafinil, have been associated with reports of serious adverse effects, such as hypertensive crisis and hyperthermia, when used in combination with MAOIs.

Likelihood Possible Evidence D
Stimulant Drugs

Theoretically, taking adrafinil with stimulant drugs might have additive stimulant effects.
Adrafinil is a precursor to the prescription drug modafinil, which has stimulant effects.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, adrafinil might alter the effects and adverse effects of warfarin.
Adrafinil is a precursor to the stimulant prescription drug modafinil. Although pharmacokinetic research shows that modafinil does not alter levels of warfarin, this study was limited to a single dose. Experts recommend monitoring international normalized ratio (INR) in patients who are taking warfarin and initiating treatment with modafinil.

Likelihood Possible Evidence D
Adrafinil full monograph & interactions

Bacopa monniera8 drug types · 930 drugs

Anticholinergic Drugs

Theoretically, concurrent use might decrease the effectiveness of both agents.
Bacopa seems to inhibit acetylcholinesterase and might increase acetylcholine levels, which could counteract the effects of anticholinergic drugs. Similarly, anticholinergic drugs might counteract the cholinergic effects of bacopa.

Likelihood Possible Evidence D
Cevimeline (Evoxac)

Theoretically, bacopa might increase the effects and adverse effects of cevimeline.
In one case, a 58-year-old female taking cevimeline long-term for Sjogren syndrome experienced hyperhidrosis, malaise, nausea, and tachycardia shortly after taking a single dose of bacopa. Symptoms resolved after two days. Cevimeline is metabolized by cytochrome P450 (CYP) 2D6 and CYP3A4, and researchers theorize that bacopa may have inhibited these isoenzymes. However, it is unclear if bacopa causes clinically significant inhibition of either CYP2D6 or CYP3A4.

Likelihood Possible Evidence D
Cholinergic Drugs

Theoretically, concurrent use of bacopa with other cholinergic drugs might have additive effects.
Bacopa seems to inhibit acetylcholinesterase and might increase acetylcholine levels. Theoretically, this could result in additive cholinergic effects when used with cholinergic drugs.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, bacopa might increase the levels and adverse effects of CYP1A2 substrates.
Research on the effects of bacopa extracts on CYP1A2 enzymes is conflicting. Some in vitro evidence shows that bacopa extract can moderately and non-competitively inhibit CYP1A2, while other in vitro evidence suggests that any effect is unlikely to be clinically significant.

Likelihood Possible Evidence D
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, bacopa might increase the levels and adverse effects of CYP2C19 substrates.
In vitro evidence suggests that bacopa extract can moderately and non-competitively inhibit CYP2C19 enzymes. It is not known whether this is clinically significant.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, bacopa might increase the levels and adverse effects of CYP2C9 substrates.
Research on the effect of bacopa extracts on CYP2C9 enzymes is conflicting. Some in vitro evidence suggests that bacopa extract can moderately and non-competitively inhibit CYP2C9, while other in vitro evidence suggests that any effect is unlikely to be clinically significant.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, bacopa might increase the levels and adverse effects of CYP3A4 substrates.
Research on the effects of bacopa extracts on CYP3A4 enzymes is conflicting. Some in vitro evidence suggests that bacopa extract can moderately and competitively inhibit CYP3A4, while other in vitro evidence suggests that any effect is unlikely to be clinically significant.

Likelihood Possible Evidence D
Thyroid Hormone

Theoretically, bacopa might have additive effects when used with thyroid hormone.
Animal research suggests that bacopa increases thyroxine (T4) levels in mice by about 40%.

Likelihood Possible Evidence D
Bacopa monniera full monograph & interactions

Dicaffeine Malate41 drug types · 655 drugs

Ephedrine

Theoretically, concomitant use might increase the risk for stimulant adverse effects.
Use of ephedrine with caffeine can increase the risk of stimulatory adverse effects. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death.

Likelihood Probable Evidence D
Adenosine (Adenocard)

Theoretically, caffeine might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Some evidence shows that caffeine is a competitive inhibitor of adenosine and can reduce the vasodilatory effects of adenosine in humans. However, other research shows that caffeine does not seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine. It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests. However, methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Possible Evidence B
Anticoagulant/Antiplatelet Drugs

Theoretically, caffeine may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Caffeine is reported to have antiplatelet activity. Theoretically, it might increase the risk of bleeding when used concomitantly with these agents; however, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Beta-Adrenergic Agonists

Theoretically, large amounts of caffeine might increase the cardiac inotropic effects of beta-agonists.

Likelihood Probable Evidence D
Carbamazepine (Tegretol)

Theoretically, caffeine might reduce the effects of carbamazepine and increase the risk for convulsions.
Animal research suggests that taking caffeine can lower the anticonvulsant effects of carbamazepine and can induce seizures when taken in doses above 400 mg/kg. Human research has shown that taking caffeine 300 mg in three divided doses along with carbamazepine 200 mg reduces the bioavailability of carbamazepine by 32% and prolongs the plasma half-life of carbamazepine 2-fold in healthy individuals.

Likelihood Possible Evidence D
Cimetidine (Tagamet)

Theoretically, cimetidine might increase the levels and adverse effects of caffeine.
Cimetidine decreases the rate of caffeine clearance by 31% to 42%.

Likelihood Likely Evidence B
Clozapine (Clozaril)

Caffeine might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
Caffeine might increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg per day inhibit clozapine metabolism. Clozapine is metabolized by cytochrome P450 1A2 (CYP1A2). Although researchers speculate that caffeine might inhibit CYP1A2, there is no reliable evidence that caffeine affects CYP1A2. There is also speculation that genetic factors might make some patients more sensitive to an interaction between clozapine and caffeine. In one case report, severe, life-threatening clozapine toxicity and multiorgan system failure occurred in a patient with schizophrenia stabilized on clozapine who consumed caffeine 600 mg daily.

Likelihood Possible Evidence B
Dipyridamole (Persantine)

Theoretically, caffeine might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Caffeine inhibits dipyridamole-induced vasodilation. It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests. Methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Probable Evidence B
Disulfiram (Antabuse)

Theoretically, disulfiram use might increase the levels and adverse effects of caffeine.
Disulfiram decreases the rate of caffeine clearance.

Likelihood Probable Evidence B
Diuretic Drugs

Theoretically, using caffeine with diuretic drugs might increase the risk of hypokalemia.
Caffeine, especially in excessive amounts, can reduce potassium levels due to stimulation of the sodium-potassium pump. Diuretics can also cause lower potassium levels.

Likelihood Possible Evidence D
Estrogens

Theoretically, estrogens might increase the levels and adverse effects of caffeine.
Estrogen inhibits caffeine metabolism.

Likelihood Probable Evidence B
Ethosuximide (Zarontin)

Theoretically, caffeine might reduce the effects of ethosuximide and increase the risk for convulsions.
Animal research suggests that caffeine 92.4 mg/kg can decrease the anticonvulsant activity of ethosuximide. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Felbamate (Felbatol)

Theoretically, caffeine might reduce the effects of felbamate and increase the risk for convulsions.
Animal research suggests that a high dose of caffeine 161.7 mg/kg can decreases the anticonvulsant activity of felbamate. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Flutamide (Eulexin)

Theoretically, caffeine might increase the levels and adverse effects of flutamide.
In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide. However, this effect has not been reported in humans.

Likelihood Probable Evidence D
Fluvoxamine (Luvox)

Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.
Fluvoxamine reduces caffeine metabolism.

Likelihood Probable Evidence D
Lithium

Abrupt caffeine withdrawal might increase the levels and adverse effects of lithium.
Caffeine has diuretic activity. When abruptly discontinued, caffeine may alter the clearance of lithium. There are two case reports of lithium tremor that worsened upon abrupt coffee withdrawal and 6 case reports of elevated serum lithium levels after reducing or eliminating caffeine intake. In one case, a male with schizoaffective disorder stabilized on lithium had an elevated lithium level after reducing his caffeine intake by 87%. At a later date, he increased his caffeine intake by 6-fold, resulting in a subtherapeutic lithium level and a recurrence of psychiatric symptoms.

Likelihood Probable Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use might increase the risk of a hypertensive crisis.
Caffeine has been shown to inhibit monoamine oxidase (MAO) A and B in laboratory studies. Concomitant intake of large amounts of caffeine with MAOIs might precipitate a hypertensive crisis. In a case report, a patient that consumed 10-12 cups of caffeinated coffee and took the MAOI tranylcypromine presented with severe hypertension. Hypertension was resolved after the patient switched to drinking decaffeinated coffee.

Likelihood Possible Evidence D
Nicotine

Theoretically, concomitant use might increase the risk of hypertension.
Concomitant use of caffeine and nicotine has been shown to have additive cardiovascular effects, including increased heart rate and blood pressure. Blood pressure was increased by 10.8/12.4 mmHg when the agents were used concomitantly.

Likelihood Probable Evidence B
Pentobarbital (Nembutal)

Theoretically, caffeine might decrease the effects of pentobarbital.
Caffeine might negate the hypnotic effects of pentobarbital.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

Theoretically, caffeine might reduce the effects of phenobarbital and increase the risk for convulsions.
Animal research suggests that caffeine can decrease the anticonvulsant activity of phenobarbital. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Phenylpropanolamine

Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of caffeine.
Concomitant use of phenylpropanolamine and caffeine might cause an additive increase in blood pressure. Phenylpropanolamine also seems to increase caffeine serum levels.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Theoretically, caffeine might reduce the effects of phenytoin and increase the risk for convulsions.
Animal research suggests that caffeine can decrease the anticonvulsant activity of phenytoin. The effect does not seem to be related to the seizure threshold-lowering effects of caffeine. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Pioglitazone (Actos)

Theoretically, caffeine might increase the levels and clinical effects of pioglitazone.
Animal research suggests that caffeine can modestly increase the maximum concentration, area under the curve, and half-life of pioglitazone, and also reduce its clearance. This increased the antidiabetic effects of pioglitazone. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Quinolone Antibiotics

Theoretically, quinolone antibiotics might increase the levels and adverse effects of caffeine.
Quinolones (also called fluoroquinolones) can decrease caffeine clearance by inhibiting cytochrome P450 1A2 (CYP1A2) enzyme.

Likelihood Probable Evidence B
Riluzole (Rilutek)

Theoretically, concomitant use might increase the levels and adverse effects of both caffeine and riluzole.
Caffeine and riluzole are both metabolized by cytochrome P450 1A2 (CYP1A2), and concomitant use might reduce the metabolism of one or both agents.

Likelihood Possible Evidence D
Dicaffeine Malate full monograph & all 41 interactions

L Theonine3 drug types · 565 drugs

Antihypertensive Drugs

Theanine might lower blood pressure, potentiating the effects of antihypertensive drugs.
Animal research shows that theanine can lower blood pressure in spontaneously hypertensive animals. Theoretically, concomitant use of theanine and antihypertensive drugs might potentiate the antihypertensive activity.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, theanine might have additive sedative effects when used in conjunction with CNS depressants. However, it is unclear if this concern is clinically relevant.
Theoretically, theanine may compete with glutamate and/or increase plasma gamma-aminobutyric acid (GABA) levels, which could cause CNS depression. In one clinical study, some subjects taking oral theanine reported drowsiness.

Likelihood Unlikely Evidence D
Serotonergic Drugs

Clinical studies regarding the effects of L-theanine on serotonin levels are conflicting. Some studies suggest it can increase serotonin levels in the brain while others report that it may decrease them. Nevertheless, there have been no reports of l-theanine being a causative agent in serotonergic-related side effects or serotonin syndrome.

Likelihood Unlikely Evidence C
L Theonine full monograph & interactions

Phosphatidylserine2 drug types · 219 drugs

Anticholinergic Drugs

Theoretically, phosphatidylserine might decrease the effectiveness anticholinergic drugs.
Phosphatidylserine is thought to increase acetylcholine levels, which could theoretically interfere with the activity of anticholinergic agents.

Likelihood Possible Evidence B
Cholinergic Drugs

Theoretically, phosphatidylserine might have additive effects with cholinergic drugs.
Phosphatidylserine is thought to increase acetylcholine levels, which could theoretically lead to additive cholinergic effects when used with cholinergic drugs.

Likelihood Possible Evidence B
Phosphatidylserine full monograph & interactions

Huperzine2 drug types · 219 drugs

Anticholinergic Drugs

Theoretically, huperzine A might decrease the effects of anticholinergic drugs.
Huperzine A has acetylcholinesterase (AChE) inhibiting effects. In animal models, huperzine A reversed cognitive deficits induced by scopolamine, an anticholinergic drug.

Likelihood Possible Evidence D
Cholinergic Drugs

Theoretically, concurrent use of huperzine A with cholinergic drugs might increase the effects and side effects of these medications.
Huperzine A can inhibit acetylcholinesterase (AChE) and might cause cumulative effects if used with cholinergic drugs.

Likelihood Possible Evidence B
Huperzine full monograph & interactions

Vinpocetine3 drug types · 208 drugs

Anticoagulant/Antiplatelet Drugs

Vinpocetine might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
Clinical research shows that vinpocetine decreases red blood cell aggregation, as well as plasma and whole blood viscosity. This effect has been seen with intravenous vinpocetine 1 mg/kg and oral vinpocetine 30 mg daily. Vinpocetine also seems to have antiplatelet effects.

Likelihood Possible Evidence B
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, vinpocetine might increase levels of drugs metabolized by CYP2C9.
In vitro research shows that vinpocetine weakly inhibits CYP2C9. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Vinpocetine might modestly increase the risk of bleeding when taken with warfarin.
Clinical research shows that the combination of warfarin and vinpocetine leads to slight increases in prothrombin time and the area under the concentration curve for warfarin. However, these increases were small, and researchers suggest that this interaction is not likely to be clinically significant in most patients.

Likelihood Possible Evidence B
Vinpocetine full monograph & interactions

Alpha GPC1 drug type · 16 drugs

Scopolamine (Transderm Scop)

Theoretically, alpha-GPC might decrease the effects of scopolamine.
A small clinical study shows that alpha-GPC can partially counteract the attention and memory impairment effects caused by scopolamine given intramuscularly. Whether alpha-GPC can decrease the beneficial anti-motion sickness effects of the scopolamine patch (Transderm Scop) is unclear.

Likelihood Possible Evidence B
Alpha GPC full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Intellect, from the product label.

8WeeksOut

See all 8WeeksOut products
Name
8WeeksOut
City
San Antonio
State
TX
ZipCode
78259
Web Address
www.8weeksoutlabs.com
Pharmacist Counseling Corner

Intellect by 8WeeksOut: Common Questions

Does Intellect by 8WeeksOut interact with any medications?
Yes. Based on its ingredients, Intellect has a known interaction with 1,454 medications, including 9 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Intellect contains 13 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take Intellect if I'm pregnant or breastfeeding?
No. Vinpocetine is FDA-warned against in pregnancy, and bacopa, phosphatidylserine, adrafinil, alpha-GPC, huperzine A, and L-theanine all lack enough safety data—they should be avoided during pregnancy and breastfeeding. Caffeine is possibly unsafe in high doses during pregnancy and passes into breast milk. Talk to your doctor before considering this product.
What does vinpocetine do in this formula?
Vinpocetine is included for its possibly effective role in dementia, though it has insufficient evidence for other uses like tinnitus and motion sickness. It decreases blood cell stickiness, which may improve blood flow to the brain but also raises bleeding risk when combined with blood thinners.
Will this product actually improve my memory and focus?
The evidence is limited. Only caffeine has strong data (it's likely effective for mental alertness), L-theanine is possibly effective for cognitive function, and phosphatidylserine and huperzine A are possibly effective for Alzheimer disease. Most other ingredients lack reliable evidence for the uses claimed here.
What are the most common side effects?
Caffeine commonly causes anxiety, insomnia, jitteriness, restlessness, and stomach upset. Bacopa causes gastrointestinal upset in about 12–30% of users. Vinpocetine, huperzine A, and other ingredients may cause headache, dizziness, nausea, and sleep disturbances. Long-term safety data are limited.
Is it safe to combine this with my prescription medications?
Not necessarily—this product has documented interactions with over 1,400 individual medications. Before starting, use the medication checker on this page with your exact prescriptions, and confirm with your doctor or pharmacist, especially if you take blood thinners, blood pressure drugs, seizure medications, antipsychotics, or stimulants.
What ingredients in this product could I not check for interactions?
We hold no interaction data for docosahexaenoic acid, noopept, N-acetyl L-tyrosine, phenylpiracetam, and oxiracetam. This doesn't mean they're safe with all medications—it means we couldn't assess them from our available sources.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Not sure if Intellect is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Intellect label
Go deeper

The Full Monographs Behind Intellect’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Vinpocetine

Interacts with 208 drugs

Vinpocetine is a lab-made compound based on a chemical from the periwinkle plant, and it is marketed mainly for memory and brain health. The evidence behind these uses is limited and not str...

Read the full Vinpocetine monograph → Herb & supplement monograph

Phosphatidylserine

Interacts with 219 drugs

Phosphatidylserine is a natural fat-like compound found in cell membranes, especially in the brain, and it is sold mainly to support memory and thinking. Some research suggests possible bene...

Read the full Phosphatidylserine monograph → Herb & supplement monograph

Bacopa

Interacts with 930 drugs

Bacopa is an Ayurvedic herb most often used for memory and thinking. Some small studies suggest it may modestly help memory when taken regularly for several weeks, but the evidence is limite...

Read the full Bacopa monograph → Herb & supplement monograph

Caffeine

Interacts with 655 drugs

Caffeine is a natural stimulant found in coffee, tea, and many other plants and products. In moderate amounts it can boost alertness and reduce tiredness for most healthy adults, but too muc...

Read the full Caffeine monograph → Herb & supplement monograph

Adrafinil

Interacts with 1,057 drugs

Adrafinil is a synthetic compound that the body converts into modafinil, a prescription wakefulness-promoting drug. It is sometimes sold as a nootropic supplement, but it is unregulated, car...

Read the full Adrafinil monograph → Herb & supplement monograph

Alpha-gpc

Interacts with 16 drugs

Alpha-GPC is a choline-containing compound used mainly for memory, brain health, and as a choline source. There is some evidence it may help cognition in people with dementia, but evidence i...

Read the full Alpha-gpc monograph → Herb & supplement monograph

Theanine

Interacts with 565 drugs

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong drowsiness. Early research suggests it may...

Read the full Theanine monograph → Herb & supplement monograph

Huperzine A

Interacts with 219 drugs

Huperzine A is a purified compound from a Chinese clubmoss that acts like a mild cholinesterase inhibitor, similar in mechanism to some prescription Alzheimer's drugs. Some small studies sug...

Read the full Huperzine A monograph →
Sources

Sources & How We Checked

Intellect's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 314 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Vinpocetine 27 references
  1. Hindmarch I, Fuchs HH, Erzigkeit H. Efficacy and tolerance of vinpocetine in ambulant patients suffering from mild to moderate organic psychosyndromes. Int Clin Psychopharmacol 1991;6:31-43. PubMed
  2. Balestreri R, Fontana L, Astengo F. A double-blind placebo controlled evaluation of the safety and efficacy of vinpocetine in the treatment of patients with chronic vascular senile cerebral dysfunction. J Am Geriatr Soc 1987;35:425-30. PubMed
  3. Akopov SE, Gabrielian ES. Effects of aspirin, dipyridamole, nifedipine and cavinton which act on platelet aggregation induced by different aggregating agents alone and in combination. Eur J Clin Pharmacol 1992;42:257-9. PubMed
  4. Kidd PM. A review of nutrients and botanicals in the integrative management of cognitive dysfunction. Altern Med Rev 1999;4:144-61..
  5. Wollschlaeger B. Efficacy of vinpocetine in the management of cognitive impairment and memory loss. JANA 2001;4:25-30.
  6. Hitzenberger G, Sommer W, Grandt R. Influence of vinpocetine on warfarin-induced inhibition of coagulation. Int J Clin Pharmacol Ther Toxicol 1990;28:323-8..
  7. Dekoninck, W. J., Jocquet, P., Jacquy, J., and Henriet, M. Comparative study of the clinical effects of vincamine + glycerol versus glycerol + placebo in the acute phase of stroke. Arzneimittelforschung. 1978;28(9):1654-1657.
  8. Fischhof, P. K., Moslinger-Gehmayr, R., Herrmann, W. M., Friedmann, A., and Russmann, D. L. Therapeutic efficacy of vincamine in dementia. Neuropsychobiology 1996;34(1):29-35. PubMed
  9. Feher, G., Koltai, K., Kesmarky, G., Horvath, B., Toth, K., Komoly, S., and Szapary, L. Effect of parenteral or oral vinpocetine on the hemorheological parameters of patients with chronic cerebrovascular diseases. Phytomedicine. 2009;16(2-3):111-117. PubMed
  10. Kuzuya, F. Effects of vinpocetine on platelet aggregability and erythrocyte deformability. Ther Hung. 1985;33(1):22-34.
  11. Kovacs, L. Cavinton in the treatment of acute stroke. Ther Hung. 1985;33(1):50-57.
  12. Osawa, M. and Maruyama, S. Effects of TCV-3B (vinpocetine) on blood viscosity in ischemic cerebrovascular diseases. Ther.Hung. 1985;33(1):7-12.
  13. Ebi, O. Open-labeled phase III clinical trials with vinpocetine in Japan. Ther.Hung. 1985;33(1):41-49.
  14. Richichi, I., Valsecchi, O., Falcone, C., Sofi, A., and Zanini, L. [A case of "torsade de pointe" during vincamine therapy]. Minerva Cardioangiol. 1978;26(3):197-200.
  15. Dany, F., Merle, L., Goudoud, J. C., Liozon, F., Blanc, P., Bouvot, J. C., Nicot, G., and Dangoumau, J. [Cardiac toxicity of vincamine: a seven cases report of ventricular arrhythmias by parenteral administration of vincamine (author's transl)]. Therapie
  16. Fenzl, E., Apecechea, M., Schaltenbr, R., and Fridel, R. Long term study concerning tolerance and efficacy of vinpocetine in elderly patients suffering from a mild to moderate organic psychosyndrome. Senile dementia: early detection 1986;580-585.
  17. Peruzza, M. and DeJacobis, M. A double-blind placebo controlled evaluation of the efficacy and safety of vinpocetine in the treatment of patients with chronic vascular or degenerative senile cerebral dysfunction. ADV THER 1986;3(4):201-209.
  18. Manconi, E., Binaghi, F., and Pitzus, F. A double-blind clinical trial of vinpocetine in the treatment of cerebral insufficiency of vascular and degenerative origin. CURR THER RES, CLIN EXP 1986;40(4):702-709.
  19. Blaha, L., Erzigkeit, H. L., Adamczyk, L. A., Freytag, L. S., and Schaltenbrand, R. Clinical evidence of the effectiveness of vinpocetine in the treatment of organic psychosyndrome. Human Psychopharmacology: Clinical & Experimental 1989;4(2):103-111. DOI
  20. Shimizu, Y., Saitoh, K., Nakayama, M., Suto, K., Daikohara, R., and Nemoto, T. Agranulocytosis induced by vinpocetine. Medicine On-line 2011;
  21. Kong L, Song C, Ye L, et al. The Effect of Vinpocetine on Human Cytochrome P450 Isoenzymes by Using a Cocktail Method. Evid Based Complement Alternat Med. 2016;2016:5017135. PubMed
  22. Vinpocetine in Dietary Supplements. FDA Food/Dietary Supplements/Products & Ingredients. Available at: http://www.fda.gov/Food/DietarySupplements/ProductsIngredients/ucm518478.htm. Accessed 6 September 2016.
  23. Statement on warning for women of childbearing age about possible safety risks of dietary supplements containing vinpocetine. FDA Food/Dietary Supplements/Products & Ingredients. Available at: https://www.fda.gov/news-events/press-announcements/statement-
  24. Zhang W, Huang Y, Li Y, et al. Efficacy and safety of vinpocetine as part of treatment for acute cerebral infarction: A randomized, open-label, controlled, multicenter CAVIN (Chinese Assessment for Vinpocetine in Neurology) trial. Clin Drug Investig 2016; PubMed
  25. National Toxicology Program. NTP technical report on the prenatal development toxicity studies of vinpocetine (CAS No. 42971-09-5) in Sprague Dawley Rats and New Zealand White Rabbits (Gavage Studies). Research Triangle Park, NC: National Toxicology Progr
  26. Gutiérrez-Farfán I, Reyes-Legorreta C, Solís-Olguín M, Alatorre-Miguel E, Verduzco-Mendoza A, Durand-Rivera A. Evaluation of vinpocetine as a therapy in patients with sensorineural hearing loss: a phase II, open-label, single-center study. J Pharmacol Sci PubMed
  27. Hu X, Guo K, Li J, et al. Postoperative ecchymoma of eyelid after botulinum toxin injection for hemifacial spasm: a case report. Front Neurol 2023;14:1171303. PubMed

See these in context on the Vinpocetine monograph →

Phosphatidylserine 9 references
  1. Crook T, Petrie W, Wells C, Massari DC. Effects of phosphatidylserine in Alzheimer's disease. Psychopharmacol Bull 1992;28:61-6.
  2. Pepping J. Phosphatidylserine. Am J Health-Syst Pharm 1999;56:2038,2043-4.
  3. Kidd PM. Phosphatidylserine; Membrane nutrient for memory. A clinical and mechanistic assessment. Altern Med Rev 1996;1:70-84.
  4. Kim HY, Akbar M, Lau A, et al. Inhibition of neuronal apoptosis by docosahexaenoic acid (22:6n-3). Role of phosphatidylserine in antiapoptotic effect. J Biol Chem 2000;275:35215-23.. PubMed
  5. Zanotti A, Valzelli L, Toffano G. Chronic phosphatidylserine treatment improves spatial memory and passive avoidance in aged rats. Psychopharmacology (Berl) 1989;99:316-21.. PubMed
  6. Schreiber S, Kampf-Sherf O, Gorfine M, et al. An open trial of plant-source derived phosphatydilserine for treatment of age-related cognitive decline. Isr J Psychiatry Relat Sci 2000;37:302-7.
  7. Pepping, J. Phosphatidylserine. Am J Health Syst.Pharm. 10-15-1999;56(20):2038, 2043-2038, 2044.
  8. Monteverde, A., Gnemmi, P., Rossi, F., Monteverde, A., and Finali, G. C. Selegiline in the treatment of mild to moderate Alzheimer-type dementia. Clin.Ther 1990;12(4):315-322.
  9. Vakhapova V, Cohen T, Richter Y, Herzog Y, Kam Y, Korczyn AD. Phosphatidylserine containing omega-3 Fatty acids may improve memory abilities in nondemented elderly individuals with memory complaints: results from an open-label extension study. Dement Geri PubMed

See these in context on the Phosphatidylserine monograph →

Bacopa 12 references
  1. Stough C, Lloyd J, Clarke J, et al. The chronic effects of an extract of Bacopa monniera (Brahmi) on cognitive function in healthy human subjects. Psychopharmacology 2001;156:481-4..
  2. Yadav SK, Jain AK, Tripathi SN, Gupta JP. Irritable bowel syndrome: therapeutic evaluation of indigenous drugs. Indian J Med Res 1989;90:496-503..
  3. Morgan A, Stevens J. Does Bacopa monnieri improve memory performance in older persons? Results of a randomized, placebo-controlled, double-blind trial. J Altern Complement Med 2010;16:753-9.
  4. Kar, A., Panda, S., and Bharti, S. Relative efficacy of three medicinal plant extracts in the alteration of thyroid hormone concentrations in male mice. J Ethnopharmacol. 2002;81(2):281-285. PubMed
  5. Mukherjee, G. D. and Dey, C. D. Clinical trial on Brahmi. I. J.Exp.Med.Sci. 1966;10(1):5-11.
  6. Kar A, Pandit S, Mukherjee K, Bahadur S, Mukherjee PK. Safety assessment of selected medicinal food plants used in Ayurveda through CYP450 enzyme inhibition study. J Sci Food Agric 2017;97(1):333-40. doi: 10.1002/jsfa.7739. PubMed
  7. Kongkeaw C, Dilokthornsakul P, Thanarangsarit P, et al. Meta-analysis of randomized controlled trials on cognitive effects of Bacopa monnieri extract. J Ethnopharmacol 2014;151(1):528-35. PubMed
  8. Ramasamy S, Kiew LV, Chung LY. Inhibition of human cytochrome P450 enzymes by Bacopa monnieri standardized extract and constituents. Molecules 2014;19(2):2588-601. PubMed
  9. Prabhakar S, Vishnu VY, Modi M, et al. Efficacy of Bacopa monnieri (Brahmi) and donepezil in Alzheimer's disease and mild cognitive impairment: a randomized double-blind parallel phase 2b study. Ann Indian Acad Neurol 2020;23(6):767-73. PubMed
  10. Acquarulo B, Tandon P, Macica CM. Suspected cholinergic toxicity due to cevimeline hydrochloride and Bacopa monnieri interaction: a case report. J Med Case Rep 2022;16(1):253. PubMed
  11. Keegan AP, Stough C, Paris D, et al. Bacopa monnieri supplementation has no effect on serum brain-derived neurotrophic factor levels but beneficially modulates nuclear factor kappa B and cyclic AMP response element-binding protein levels in healthy elderl
  12. Yaworski AM, Blyumin M, Chang T, Mammen AL, Greene M. Necrotizing myopathy with elevated anti-HMGCR antibodies following exposure to the supplement Bacopa. Muscle Nerve 2023;67(2):E1-E3.

See these in context on the Bacopa monograph →

Caffeine 236 references
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  2. Harder S, Fuhr U, Staib AH, Wolff T. Ciprofloxacin-caffeine: a drug interaction established using in vivo and in vitro investigations. Am J Med 1989;87:89S-91S. PubMed
  3. Carbo M, Segura J, De la Torre R, et al. Effect of quinolones on caffeine disposition. Clin Pharmacol Ther 1989;45:234-40. PubMed
  4. Healy DP, Polk RE, Kanawati L, et al. Interaction between oral ciprofloxacin and caffeine in normal volunteers. Antimicrob Agents Chemother 1989;33:474-8. PubMed
  5. Mester R, Toren P, Mizrachi I, et al. Caffeine withdrawal increases lithium blood levels. Biol Psychiatry 1995;37:348-50. PubMed
  6. Jefferson JW. Lithium tremor and caffeine intake: two cases of drinking less and shaking more. J Clin Psychiatry 1988;49:72-3.
  7. Joeres R, Klinker H, Heusler H, et al. Influence of mexiletine on caffeine elimination. Pharmacol Ther 1987;33:163-9. PubMed
  8. Vahedi K, Domingo V, Amarenco P, Bousser MG. Ischemic stroke in a sportsman who consumed MaHuang extract and creatine monohydrate for bodybuilding. J Neurol Neurosurg Psychiatr 2000;68:112-3.
  9. Wakabayashi K, Kono S, Shinchi K, et al. Habitual coffee consumption and blood pressure: A study of self-defense officials in Japan. Eur J Epidemiol 1998;14:669-73. PubMed
  10. Hodgson JM, Puddey IB, Burke V, et al. Effects on blood pressure of drinking green and black tea. J Hypertens 1999;17:457-63. PubMed
  11. Rapuri PB, Gallagher JC, Kinyamu HK, Ryschon KL. Caffeine intake increases the rate of bone loss in elderly women and interacts with vitamin D receptor genotypes. Am J Clin Nutr 2001;74:694-700. PubMed
  12. The National Toxicology Program (NTP). Caffeine. Center for the Evaluation of Risks to Human Reproduction (CERHR). Available at: http://cerhr.niehs.nih.gov/common/caffeine.html.
  13. Klebanoff MA, Levine RJ, DerSimonian R, et al. Maternal serum paraxanthine, a caffeine metabolite, and the risk of spontaneous abortion. N Engl J Med 1999;341:1639-44. PubMed
  14. Eskenazi B. Caffeine—filtering the facts. N Engl J Med 1999;341:1688-9. PubMed
  15. Fernandes O, Sabharwal M, Smiley T, et al. Moderate to heavy caffeine consumption during pregnancy and relationship to spontaneous abortion and abnormal fetal growth: a meta-analysis. Reprod Toxicol 1998;12:435-44. PubMed
  16. Pollock BG, Wylie M, Stack JA, et al. Inhibition of caffeine metabolism by estrogen replacement therapy in postmenopausal women. J Clin Pharmacol 1999;39:936-40. PubMed
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  18. Dews PB, Curtis GL, Hanford KJ, O'Brien CP. The frequency of caffeine withdrawal in a population-based survey and in a controlled, blinded pilot experiment. J Clin Pharmacol 1999;39:1221-32. PubMed
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  23. Watson JM, Jenkins EJ, Hamilton P, et al. Influence of caffeine on the frequency and perception of hypoglycemia in free-living patients with type 1 diabetes. Diabetes Care 2000;23:455-9. PubMed
  24. Lloyd T, Johnson-Rollings N, Eggli DF, et al. Bone status among postmenopausal women with different habitual caffeine intakes: a longitudinal investigation. J Am Coll Nutr 2000;19:256-61. PubMed
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  45. Abernethy DR, Todd EL. Impairment of caffeine clearance by chronic use of low-dose oestrogen-containing oral contraceptives. Eur J Clin Pharmacol 1985;28:425-8. PubMed
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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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