Major interaction on record — check this product against your medications before combining. Based on 14 of 17 ingredients. Check your meds →
Dietary supplement

Royal XXI Queen Ingredients & Drug Interactions

by 1st Phorm

Capsule Category: Other Combinations
Most serious interaction: Major
The interaction bottom line Most serious interaction: Major

Royal XXI Queen is a dietary supplement by 1st Phorm with 17 active ingredients. Its ingredients are commonly taken for stress and anxiety, sleep problems, fatigue and low energy.Based on those ingredients, 1,648 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Ashwagandha, Bacopa monniera, Higenamine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Royal XXI Queen by 1st Phorm

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

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 1 of its 17 active ingredients.
  • “Nootro-Q Blend” is a proprietary blend — the label gives one combined amount (275 mg) without saying how much of each component you get.
  • “Valley Matrix” is a proprietary blend — the label gives one combined amount (235 mg) without saying how much of each component you get.
  • “FAC-T Blend” is a proprietary blend — the label gives one combined amount (50 mg) without saying how much of each component you get.

Royal XXI Queen contains 17 ingredients, several of which are active compounds. The main players are L-Theanine and Theacrine (amino-acid-like compounds), Sulbutiamine (a form of B1 vitamin), CDP Choline and Choline Bitartrate (choline sources for brain function), Huperzine A (an alkaloid that affects acetylcholine), Ashwagandha (an adaptogenic herb), Hordenine, Higenamine, and Damiana (stimulant-type compounds), Bacopa monniera (an herb used for cognition), Dimethylethanolamine (also called Deanol), and two forms of caffeine.

The product also contains inactive ingredients—gelatin capsule material, silicon dioxide, and magnesium stearate as processing aids.

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: Control appetite, boost energy, minimize hormone fluctuation.
  • We looked for evidence on: Anxiety, Athletic performance, Attention deficit-hyperactivity disorder (ADHD), Cognitive function, Cognitive impairment, Depression — and 4 related terms.
  • The strongest evidence on file: Caffeine is rated "Likely Effective" for Athletic performance (Natural Medicines).
  • Also on file: Ashwagandha is rated "Possibly Effective" for Anxiety, Generalized anxiety disorder (GAD).
  • Also on file: Theanine is rated "Possibly Effective" for Cognitive function.

The evidence for what this product actually does is mixed and often thin. L-Theanine is possibly effective for cognitive function, but evidence for its other claimed uses—age-related cognitive decline, Alzheimer's, anxiety, and obsessive-compulsive disorder—is insufficient.

Theacrine, sulbutiamine, damiana, and higenamine all lack reliable evidence for athletic performance, cognition, fatigue, or mental alertness. CDP Choline is possibly effective for age-related cognitive decline and possibly effective for glaucoma, but ineffective for stroke recovery.

Huperzine A is possibly effective for Alzheimer's disease but has insufficient evidence for memory, cognitive impairment, vascular dementia, depression, and athletic performance. Bacopa's evidence is too limited to rate across its claimed uses.

Caffeine is well-established as effective for alertness and athletic performance and effective for neonatal apnea. Deanol is rated likely ineffective for Alzheimer's and tardive dyskinesia.

Ashwagandha is possibly effective for insomnia, anxiety, stress, and generalized anxiety disorder. Overall, you're getting a few ingredients with some evidence backing specific claims, but many with little to no proven benefit.

The evidence, ingredient by ingredient Ashwagandha Damiana Sulbutiamine Citicoline Huperzine A Choline Deanol Bacopa

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 13 of the 14 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 11 of 14.
  • General safety write-ups exist for 14 of 14.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most of these ingredients are generally well tolerated short-term in healthy adults, but long-term safety data are limited across the board. The biggest safety concerns are with ashwagandha—rare but serious cases of acute hepatitis and liver failure have been reported—and higenamine, which has cardiac stimulant effects and is banned in competitive sports.

Huperzine A can cause cholinergic side effects (nausea, vomiting, diarrhea, blurred vision, dry mouth, constipation) at higher doses. L-Theanine may cause headaches, drowsiness, or (rarely) facial tics.

Caffeine at high doses causes anxiety, insomnia, tremor, and heart palpitations. Bacopa commonly causes gastrointestinal upset (12–30% of users report it).

Choline Bitartrate at doses above 3.5 grams daily can cause nausea, vomiting, and fishy body odor. Theacrine, sulbutiamine, CDP Choline, and damiana are generally well tolerated but have limited human safety data.

For pregnancy, the data advise against L-Theanine, Theacrine, Sulbutiamine, CDP Choline, Huperzine A, Ashwagandha, Hordenine, Damiana, Higenamine, and Bacopa. Caffeine should be limited in pregnancy (ask your doctor about safe amounts).

Choline is considered likely safe in pregnancy but should only be used at doses advised by your doctor. Deanol has insufficient data in pregnancy.

For breastfeeding, most ingredients lack enough safety data; caffeine in small amounts is usually acceptable but can affect the baby, and choline needs are higher while breastfeeding (use supplements only under professional guidance).

Side effects, ingredient by ingredient Ashwagandha Damiana Sulbutiamine Citicoline Huperzine A Choline Deanol Bacopa

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?
  • 12 of the 14 matched ingredients can interact with medications — Choline, Deanol, Damiana, Bacopa, Huperzine A, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; lithium.
  • For scale: 1,649 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.

Before you take Royal XXI Queen, double-check with your pharmacist if you're on ephedrine (Major risk with caffeine), or any of these Moderate-severity categories: blood pressure medications, blood sugar medications, sedatives and benzodiazepines, blood thinners or antiplatelet drugs, heart stimulants, immune-suppressing drugs, thyroid hormones, liver-damaging drugs, older antidepressants (MAOIs), seizure-prevention drugs, antibiotics (quinolones), stomach acid reducers, or medications processed through your liver's CYP2D6 or CYP3A4 pathways. We could not check interactions for Evodiamine, N-Acetyl-Tyrosine, or Queen Complex.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with clinical evidence supporting its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

Royal XXI Queen is a multi-ingredient cognitive and energy product built mainly on caffeine, ashwagandha, and several cholinergic compounds. If you take blood pressure meds, diabetes drugs, sedatives, blood thinners, immune suppressants, heart drugs, antidepressants (especially MAOIs), or seizure preventers, you need to check each of your medications against this product before starting.

Pregnant or breastfeeding people should not take it without talking to their doctor or pharmacist first. The evidence that most of its ingredients actually work for what they're claimed to do is weak or absent.

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

Assessment coverage: 15 of 17 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Dec 22, 2019.

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 Royal XXI Queen, straight from the product label.

Brand 1st Phorm
Net contents 80 Capsule(s)
Market status On market
Date entered into DSLD Dec 22, 2019
DSLD ID 211508
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult Female (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 Royal XXI Queen by 1st Phorm, 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:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
80
IngredientAmount% DV
L-Theanine0 NP--
Theacrine0 NP--
Sulbutiamine0 NP--
CDP Choline0 NP--
Huperzine A0 NP--
Evodiamine0 NP--
Ashwagandha0 NP--
Choline Bitartrate0 NP--
N-Acetyl-Tyrosine0 NP--
Hordenine0 NP--
Damiana0 NP--
Higenamine0 NP--
Dimethylethanolamine0 NP--
Bacopa monniera0 NP--
Nootro-Q Blend275 mg--
micro-encapsulated sustained release Caffeine Anhydrous0 NP--
Valley Matrix235 mg--
1,3,7-Trimethylxanthine0 NP--
FAC-T Blend50 mg--
Queen Complex50 mg--

Other ingredients: Gelatin, Silicon Dioxide, 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.
General Statements

Cutting-edge feminine Nothing compares

Formulation

Control appetite & curb cravings Incredible focused energy boost Minimize hormone fluctuation

Thermo-lipolytic formula

FDA Statement of Identity

Dietary Supplement

See for yourself

Royal XXI Queen by 1st Phorm label

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

What’s inside

The Ingredients in Royal XXI Queen by 1st Phorm

These are the 17 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container80 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.

Ashwagandha

Interacts with
1,372 drugs
0 NP per serving

Ashwagandha is an Ayurvedic herb most often taken to help with stress, anxiety, and sleep, and some small studies suggest it may help, though the evid...

Ashwagandha monograph & interactions

Damiana

Interacts with
86 drugs
0 NP per serving

Damiana is a traditional herb most famous as an aphrodisiac and mild mood-lifter, but solid human evidence for any of its uses is very limited. It is...

Damiana monograph & interactions

Nootro-Q Blend

275 mg per serving

FAC-T Blend

50 mg per serving

Queen Complex

Interacts with
804 drugs
50 mg per serving

Ayahuasca is a powerful psychoactive brew that combines a DMT-containing plant with a vine that allows the DMT to take effect, causing intense halluci...

Queen Complex monograph & interactions

Other (inactive) ingredients: Gelatin, Silicon Dioxide, Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Royal XXI Queen by 1st Phorm Drug Interactions

Want to check YOUR meds against Royal XXI Queen?

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
1,648Drugs
8 Major 1,629 Moderate 11 Minor

Ingredients driving the most interactions

Ashwagandha 1,372

Each ingredient & the kinds of drugs it affects

For each ingredient in Royal XXI Queen 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.

Ashwagandha10 drug types · 1,372 drugs

Antidiabetes Drugs

Theoretically, taking ashwagandha with antidiabetes drugs might increase the risk of hypoglycemia.
There is preliminary clinical evidence suggesting that ashwagandha might lower blood glucose levels. Theoretically, ashwagandha might have additive effects when used with antidiabetes drugs and increase the risk of hypoglycemia.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, taking ashwagandha with antihypertensive drugs might increase the risk of hypotension.
Animal research suggests that ashwagandha might lower systolic and diastolic blood pressure. Theoretically, ashwagandha might have additive effects when used with antihypertensive drugs and increase the risk of hypotension.

Likelihood Possible Evidence D
Benzodiazepines

Theoretically, taking ashwagandha might increase the sedative effects of benzodiazepines.
There is preliminary evidence that ashwagandha might have an additive effect with diazepam (Valium) and clonazepam (Klonopin). This may also occur with other benzodiazepines.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, taking ashwagandha might increase the sedative effects of CNS depressants.
Ashwagandha seems to have sedative effects. Theoretically, this may potentiate the effects of barbiturates, other sedatives, and anxiolytics.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Theoretically, taking ashwagandha with hepatotoxic drugs might increase the risk of liver damage.
Ashwagandha has been linked to cases of acute hepatitis, liver failure, hepatic encephalopathy, autoimmune hepatitis, the need for liver transplantation, and death due to liver failure.

Likelihood Possible Evidence D
Immunosuppressants

Theoretically, taking ashwagandha might decrease the effects of immunosuppressants.
Ashwagandha has demonstrated immunostimulant effects in humans. Animal research has shown that ashwagandha can attenuate the immunosuppression caused by cyclophosphamide.

Likelihood Possible Evidence D
Thyroid Hormone

Ashwagandha might increase the effects and adverse effects of thyroid hormone.
Concomitant use of ashwagandha with thyroid hormones may cause additive therapeutic and adverse effects. Preliminary clinical research and animal studies suggest that ashwagandha boosts thyroid hormone synthesis and secretion. In one clinical study, ashwagandha increased triiodothyronine (T3) and thyroxine (T4) levels by 41.5% and 19.6%, respectively, and reduced serum TSH levels by 17.4% from baseline in adults with subclinical hypothyroidism.

Likelihood Probable Evidence B
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, ashwagandha might decrease the levels and clinical effects of CYP1A2 substrates.
In vitro research shows that ashwagandha extract induces CYP1A2 enzymes.

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

Theoretically, ashwagandha might decrease the levels and clinical effects of CYP3A4 substrates.
In vitro research shows that ashwagandha extract induces CYP3A4 enzymes.

Likelihood Possible Evidence D
Serotonergic Drugs

Some animal studies have reported that ashwagandha can enhance serotonergic transmission by altering certain serotonin (5-HT) receptors. However, there is no evidence to suggest that ashwagandha increases the risk of serotonin-related effects, and there have been no published case reports of serotonin syndrome when combined with other serotonergic drugs. Nevertheless, due to the lack of extensive studies on the matter and the fact that ashwagandha appears to affect serotonergic pathways, it would be prudent to exercise caution when combining it with drugs that affect serotonin. [References: - Effects of Withania somnifera (Ashwaga ndha) on Stress and the Stress-Related Neuropsychiatric Disorders Anxiety, Depression, and Insomnia. Curr Neuropharmacol. 2021 Sep 14; 19: 1468–1495. - A Prospective, Randomized Double-Blind, Placebo-Controlled Study of Safety and Efficacy of a High-Concentration Full-Spectrum Extract of Ashwagandha Root in Reducing Stress and Anxiety in Adults. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3573577/]

Likelihood Possible Evidence C

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

Higenamine5 drug types · 891 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, higenamine might increase the risk of bleeding or bruising when taken with anticoagulant/antiplatelet drugs.
Animal research shows that higenamine inhibits platelet aggregation and reduces the size of thrombus formation.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, higenamine might increase the levels and clinical effects of drugs metabolized by CYP2D6.
In vitro research shows that higenamine inhibits CYP2D6 enzymes. However, this effect has not been reported in humans.

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

Theoretically, higenamine might increase the levels and clinical effects drugs metabolized by CYP3A4.
In vitro research shows that higenamine inhibits CYP3A4 enzymes by 21%. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Stimulant Drugs

Theoretically, higenamine might increase the risk of cardiovascular toxicity when taken with stimulant drugs.
Higenamine has stimulant effects due to agonist activity at beta2-adrenoreceptors. In cardiac muscle, higenamine appears to have a positive inotropic effect and increase heart rate. However, it does not appear to increase blood pressure.

Likelihood Possible Evidence D
Propranolol (Inderal)

Theoretically, the positive inotropic effects of higenamine might be reduced by propranolol.
Animal research shows that higenamine has a positive inotropic effect on the heart, and administering propranolol appears to block this cardiac effect. In animals, propranolol also appears to inhibit corpus cavernosum relaxation induced by higenamine.

Likelihood Possible Evidence D

Queen Complex4 drug types · 804 drugs

Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, ayahuasca might increase plasma concentrations of CYP2D6 substrates.
Ayahuasca contains beta-carboline alkaloids, including harmine and harmaline. In vitro research suggests that the beta-carboline alkaloids might inhibit CYP2D6 enzymes. This effect has not been reported in humans.

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

Theoretically, ayahuasca might increase plasma concentrations of CYP3A4 substrates.
Ayahuasca contains beta-carboline alkaloids. In vitro research suggests that beta-carboline alkaloids competitively inhibit CYP3A4 enzymes. This effect has not been reported in humans.

Likelihood Possible Evidence D
Dopamine Agonists

Theoretically, ayahuasca might have additive effects when used with dopamine agonists.
Ayahuasca contains the beta-carboline constituent harmine. Animal research shows that harmine increases extracellular dopamine levels.

Likelihood Possible Evidence D
Serotonergic Drugs

Theoretically, ayahuasca might increase levels of serotonin, which may have additive effects with serotonergic drugs.
In vitro and animal research shows that harmaline and harmine, constituents of ayahuasca, strongly and reversibly inhibit monoamine oxidase A and weakly inhibit monoamine oxidase B. The dimethyltryptamine and tetrahydroharmine constituents of ayahuasca have also demonstrated serotonergic activity. A case of serotonin syndrome characterized by tremors, sweating, shivering, confusion, nausea, vomiting, and disorientation has been reported in a 36-year-old male who consumed 100 mL of ayahuasca while taking fluoxetine 20 mg daily. Combining serotonergic drugs with ayahuasca might increase the risk of serotonergic side effects including serotonin syndrome and cerebral vasoconstrictive disorders.

Likelihood Possible Evidence D

micro-encapsulated sustained release Caffeine Anhydrous41 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

L-Theanine3 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

Hordenine3 drug types · 329 drugs

Monoamine Oxidase Inhibitors (Maois)

Hordenine is structurally similar to tyramine In vitro research shows that hordenine is a selective substrate for monoamine oxidase-B in the liver. Theoretically, concomitant use of hordenine with MAOIs might increase blood pressure, potentially leading to a hypertensive crisis.
Some MAOIs include isocarboxazid (Marplan), phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), and tranylcypromine (Parnate).

Likelihood Possible Evidence D
Stimulant Drugs

Hordenine is structurally similar to N-methyltyramine and synephrine, constituents in bitter orange known to have stimulant properties. Theoretically, taking hordenine with drugs with stimulant properties might increase the risk of hypertension and other adverse cardiovascular effects.
Some of these drugs include amphetamine, caffeine, methylphenidate, pseudoephedrine, and many others.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Hordenine weakly inhibits cytochrome P450 2D6 (CYP2D6) enzymes in vitro. Theoretically, hordenine might increase the levels of CYP2D6 substrates.
Some of drugs that are CYP2D6 substrates include amitriptyline (Elavil), clozapine (Clozaril), codeine, desipramine (Norpramin), donepezil (Aricept), fentanyl (Duragesic), flecainide (Tambocor), fluoxetine (Prozac), meperidine (Demerol), methadone (Dolophine), metoprolol (Lopressor, Toprol XL), olanzapine (Zyprexa), ondansetron (Zofran), tramadol (Ultram), trazodone (Desyrel), and others.

Likelihood Possible Evidence D

Theacrine1 drug type · 248 drugs

Cns Depressants

Theoretically, theacrine might alter the effects of CNS depressants.
Animal research shows that low doses of theacrine have sedating effects, whereas high doses might have stimulant effects. Depending on the dose of theacrine used, it might increase or decrease the effects of CNS depressants. However, these effects have not yet been reported in humans.

Likelihood Possible Evidence D

Huperzine A2 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

Dimethylethanolamine2 drug types · 219 drugs

Anticholinergic Drugs

Theoretically, deanol might decrease the effectiveness of anticholinergic drugs.
Deanol is thought to increase acetylcholine levels.

Likelihood Unlikely Evidence D
Cholinergic Drugs

Theoretically, deanol might increase the effects and adverse effects of cholinergic drugs.
Deanol is thought to increase acetylcholine levels.

Likelihood Unlikely Evidence D

Damiana1 drug type · 86 drugs

Antidiabetes Drugs

Theoretically, taking damiana with antidiabetes drugs might increase the risk of hypoglycemia.
Animal research shows that taking damiana lowers blood glucose level.

Likelihood Possible Evidence D

Choline Bitartrate1 drug type · 16 drugs

Atropine

Theoretically, choline might decrease the effects of atropine in the brain.
Animal research shows that administering choline one hour before administering atropine can attenuate atropine-induced decreases in brain levels of acetylcholine. Theoretically, concomitant use of choline and atropine may decrease the effects of atropine.

Likelihood Possible Evidence D
The maker

Brand information

Manufacturer and brand details for Royal XXI Queen, from the product label.

1st Phorm

Name
1st Phorm International LLC
Pharmacist Counseling Corner

Royal XXI Queen by 1st Phorm: Common Questions

Does Royal XXI Queen by 1st Phorm interact with any medications?
Yes. Based on its ingredients, Royal XXI Queen has a known interaction with 1,648 medications, including 8 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Royal XXI Queen contains 17 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 this while I'm pregnant or breastfeeding?
The safety data advise against most ingredients in this product during pregnancy—there isn't enough information to know they're safe. For breastfeeding, caffeine in small amounts is usually acceptable but can affect the baby, and most other ingredients lack enough safety data. Talk to your doctor or pharmacist for personalized advice; don't start this on your own.
What's L-Theanine actually good for?
L-Theanine is possibly effective for cognitive function, but we don't have solid evidence it works for age-related mental decline, Alzheimer's, anxiety, or OCD. It's possibly effective for one thing—that's about it.
Does ashwagandha in this product actually work?
Ashwagandha is possibly effective for insomnia, anxiety, stress, and generalized anxiety disorder. However, it's best to know that rare but serious liver damage has been reported with ashwagandha, so it's not a casual supplement—use it with medical guidance if you decide to use it at all.
Will this help my energy and focus?
Caffeine will definitely give you energy and alertness—that's well established. Most of the other ingredients (theacrine, hordenine, higenamine) lack solid evidence for athletic performance, mental sharpness, or fatigue. You're mainly paying for the caffeine effect.
What side effects should I watch for?
Common ones include headache, nausea, insomnia, anxiety, and jitteriness (mostly from caffeine). Bacopa commonly causes stomach upset in about 12–30% of users. Ashwagandha can cause drowsiness. At high doses, choline causes fishy body odor and gastrointestinal upset. If you have a heart condition or take heart drugs, higenamine's cardiac effects are a real concern.
Is this safe for long-term use?
Long-term safety data are limited for most ingredients here. Short-term use in healthy adults is generally tolerated, but we don't have enough information to say whether taking it for months or years is safe. Talk to your pharmacist if you're thinking of using it regularly.

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

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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.

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Go deeper

The Full Monographs Behind Royal XXI Queen’s Ingredients

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

Herb & supplement monograph

Ashwagandha

Interacts with 1,372 drugs

Ashwagandha is an Ayurvedic herb most often taken to help with stress, anxiety, and sleep, and some small studies suggest it may help, though the evidence is still limited. It is generally w...

Read the full Ashwagandha monograph →
Herb & supplement monograph

Damiana

Interacts with 86 drugs

Damiana is a traditional herb most famous as an aphrodisiac and mild mood-lifter, but solid human evidence for any of its uses is very limited. It is generally well tolerated in the small am...

Read the full Damiana monograph →
Herb & supplement monograph

Sulbutiamine

Sulbutiamine is a man-made, fat-soluble form of vitamin B1 (thiamine) developed in Japan, often taken for fatigue and to support mental energy and focus. Human evidence is limited and mostly...

Read the full Sulbutiamine monograph →
Herb & supplement monograph

Citicoline

Citicoline is a naturally occurring compound involved in making brain cell membranes and the messenger chemical acetylcholine. It is popularly taken for memory, focus, and brain aging, and s...

Read the full Citicoline 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 →
Herb & supplement monograph

Choline

Interacts with 16 drugs

Choline is an essential nutrient your body needs for liver function, brain health, and nerve signaling, and many people get enough from foods like eggs, meat, and fish. Supplements may help...

Read the full Choline monograph →
Herb & supplement monograph

Deanol

Interacts with 219 drugs

Deanol (DMAE) is a compound related to choline that is marketed for memory, focus, and mood, but solid human evidence for most of these uses is limited or mixed. It can cause side effects in...

Read the full Deanol 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

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

Theacrine

Interacts with 248 drugs

Theacrine is a caffeine-like compound found naturally in certain tea plants and is sold in supplements for energy, focus, and mood. Early human studies suggest it may give a stimulant-like b...

Read the full Theacrine 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

Hordenine

Interacts with 329 drugs

Hordenine is a natural alkaloid found in barley and some cacti that is marketed as a stimulant for energy, focus, and fat loss, but solid human evidence for these benefits is lacking. Its sa...

Read the full Hordenine monograph →
Herb & supplement monograph

Higenamine

Interacts with 891 drugs

Higenamine is a plant-based stimulant compound added to many weight-loss and pre-workout supplements, but there is very little human evidence that it works and real concerns about heart and...

Read the full Higenamine monograph →
Herb & supplement monograph

Ayahuasca

Interacts with 804 drugs

Ayahuasca is a powerful psychoactive brew that combines a DMT-containing plant with a vine that allows the DMT to take effect, causing intense hallucinations. It is illegal in many places, c...

Read the full Ayahuasca monograph →
Sources

Sources & How We Checked

Royal XXI Queen'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 395 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.

Theanine 6 references
  1. Yokogoshi H, Kobayashi M. Hypotensive effect of gamma-glutamylethylamide in spontaneously hypertensive rats. Life Sci 1998;62:1065-8.
  2. Haskell, C. F., Kennedy, D. O., Milne, A. L., Wesnes, K. A., and Scholey, A. B. The effects of L-theanine, caffeine and their combination on cognition and mood. Biol.Psychol. 2008;77(2):113-122. PubMed
  3. Yokogoshi, H., Kato, Y., Sagesaka, Y. M., Takihara-Matsuura, T., Kakuda, T., and Takeuchi, N. Reduction effect of theanine on blood pressure and brain 5-hydroxyindoles in spontaneously hypertensive rats. Biosci.Biotechnol.Biochem. 1995;59(4):615-618. PubMed
  4. Lyon MR, Kapoor MP, Juneja LR. The effects of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD): a randomized, double-blind, placebo-controlled clinical trial. Altern Med Rev. 2011;16(4):348-
  5. Hidese S, Ota M, Wakabayashi C, et al. Effects of chronic l-theanine administration in patients with major depressive disorder: an open-label study. Acta Neuropsychiatr 2017;29(2):72-9.
  6. Tsuchiya T, Honda H, Oikawa M, et al. Oral administration of the amino acids cystine and theanine attenuates the adverse events of S-1 adjuvant chemotherapy in gastrointestinal cancer patients. Int J Clin Oncol 2016;21(6):1085-90. PubMed

See these in context on the Theanine monograph →

Theacrine 1 reference
  1. Xu JK, Kurihara H, Zhao L, Yao XS. Theacrine, a special purine alkaloid with sedative and hypnotic properties from Cammelia assamica var. kucha in mice. J Asian Nat Prod Res 2007;9(6-8):665-72.

See these in context on the Theacrine monograph →

Sulbutiamine 4 references
  1. Shah S. Adjuvant role of vitamin B analogue (sulbutiamine) with anti-infective treatment in infection associated asthenia. J Assoc Physicians India. 2003;51:891-5.
  2. Loo H, Poirier M, Ollat H, et al. [Effects of subutiamine (Arcalion 200) on psycho-behavioral inhibition in major depressive episodes]. Encephale. 2000;26(2):70-5.
  3. Kiew K, Wan Mohamad W, Ridzuan A, et al. Effects of sulbutiamine on diabetic polyneuropathy: an open randomized controlled study in type 2 diabetics. Malays J Med Sci. 2002;9(1):21-7.
  4. Sevim S, Kaleagasi H, Tasdelen B. Sulbutiamine shows promising results in reducing fatigue in patients with multiple sclerosis. Mult Scler Relat Disord. 2017;16:40-43. PubMed

See these in context on the Sulbutiamine monograph →

Citicoline 11 references
  1. Spiers PA, Myers D, Hochanadel GS, et al. Citicoline improves verbal memory in aging. Arch Neurol 1996;53:441-8. PubMed
  2. Fioravanti M, Yanagi M. Cytidinediphosphocholine (CDP-choline) for cognitive and behavioural disturbances associated with chronic cerebral disorders in the elderly. Cochrane Database Syst Rev 2005;(2):CD000269. PubMed
  3. Conant R, Schauss AG. Therapeutic applications of citicoline for stroke and cognitive function in the elderly: A review of the literature. Altern Med Rev 2004;9:17-31.
  4. Warach, S., Pettigrew, L. C., Dashe, J. F., Pullicino, P., Lefkowitz, D. M., Sabounjian, L., Harnett, K., Schwiderski, U., and Gammans, R. Effect of citicoline on ischemic lesions as measured by diffusion-weighted magnetic resonance imaging. Citicoline 0 DOI
  5. Lukas, S. E., Kouri, E. M., Rhee, C., Madrid, A., and Renshaw, P. F. Effects of short-term citicoline treatment on acute cocaine intoxication and cardiovascular effects. Psychopharmacology.(Berl.) 2001;157(2):163-167. PubMed
  6. Dinsdale, J. R., Griffiths, G. K., Castello, J., Maddock, J., Ortiz, J. A., and Aylward, M. CDP-choline: repeated oral dose tolerance studies in adult healthy volunteers. Arzneimittelforschung. 1983;33(7A):1061-1065.
  7. Clark BC, Georgekutty J, Berul CI. Myocardial ischemia secondary to synthetic cannabinoid (K2) use in pediatric patients. J Pediatr 2015;167(3):757-61.e1. PubMed
  8. Ghajar A, Gholamian F, Tabatabei-Motlagh M, et al. Citicoline (CDP-choline) add-on therapy to risperidone for treatment of negative symptoms in patients with stable schizophrenia: a double-blind, randomized placebo-controlled trial. Hum Psychopharmacol. 2
  9. Castagna A, Manzo C, Fabbo A, Lacava R, Ruberto C, Ruotolo G. The CITIMERIVA Study: CITIcoline plus MEmantina plus RIVAstigmine in Older Patients Affected with Alzheimer's Disease. Clin Drug Investig. 2021 Feb;41(2):177-182. PubMed
  10. Jeong H, Yoon S, Sung YH, et al. Effects of cytidine-5'-diphosphate choline on gray matter volumes in methamphetamine-dependent patients: A randomized, double-blind, placebo-controlled study. J Psychiatr Res 2021;143:215-221. PubMed
  11. Nakazaki E, Mah E, Sanoshy K, Citrolo D, Watanabe F. Citicoline and Memory Function in Healthy Older Adults: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial. J Nutr 2021;151(8):2153-2160. PubMed

See these in context on the Citicoline monograph →

Huperzine A 13 references
  1. Skolnick AA. Old Chinese herbal medicine used for fever yields possible new Alzheimer Disease therapy. JAMA 1997;277:776. DOI
  2. Ye JW, Cai JX, Wang LM, Tang XC. Improving effects of huperzine A on spatial working memory in aged monkeys and young adult monkeys with experimental cognitive impairment. J Pharmacol Exp Ther 1999;288:814-9.. DOI
  3. Wang T, Tang XC. Reversal of scopolamine-induced deficits in radial maze performance by (-)-huperzine A: comparison with E2020 and tacrine. Eur J Pharmacol 1998;349:137-42. PubMed
  4. Xu SS, Gao ZX, Weng Z, et al. Efficacy of tablet huperzine-A on memory, cognition, and behavior in Alzheimer's disease. Zhongguo Yao Li Xue Bao 1995;16:391-5.
  5. Zhang RW, Tang XC, Han YY, et al. [Drug evaluation of huperzine A in the treatment of senile memory disorders]. Chung Kuo Yao Li Hsueh Pao 1991;12:250-2.
  6. Xu SS, Cai ZY, Qu ZW, et al. Huperzine-A in capsules and tablets for treating patients with Alzheimer disease. Zhongguo Yao Li Xue Bao 1999;20:486-90.
  7. Felgenhauer N, Zilker T, Worek F, Eyer P. Intoxication with huperzine A, a potent anticholinesterase found in the fir club moss. J Toxicol Clin Toxicol 2000;38:803-8.. PubMed
  8. Zhang, Z., Wang, X., Chen, Q., Shu, L., Wang, J., and Shan, G. [Clinical efficacy and safety of huperzine Alpha in treatment of mild to moderate Alzheimer disease, a placebo-controlled, double-blind, randomized trial]. Zhonghua Yi Xue Za Zhi 7-25-2002;82
  9. Cheng, D. H., Ren, H., and Tang, X. C. Huperzine A, a novel promising acetylcholinesterase inhibitor. Neuroreport 12-20-1996;8(1):97-101. PubMed
  10. Wang BS, Wang H, Wei ZH, Song YY, Zhang L, Chen HZ. Efficacy and safety of natural acetylcholinesterase inhibitor huperzine A in the treatment of Alzheimer's disease: an updated meta-analysis. J Neural Transm (Vienna) 2009;116(4):457-65. PubMed
  11. Xu ZQ, Liang XM, Juan-Wu, Zhang YF, Zhu CX, Jiang XJ. Treatment with Huperzine A improves cognition in vascular dementia patients. Cell Biochem Biophys 2012;62(1):55-8. PubMed
  12. Yang G, Wang Y, Tian J, Liu JP. Huperzine A for Alzheimer's disease: a systematic review and meta-analysis of randomized clinical trials. PLoS One 2013;8(9):e74916. PubMed
  13. Xing SH, Zhu CX, Zhang R, An L. Huperzine a in the treatment of Alzheimer's disease and vascular dementia: a meta-analysis. Evid Based Complement Alternat Med 2014;2014:363985. PubMed

See these in context on the Huperzine A monograph →

Ashwagandha 32 references
  1. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  2. Upton R, ed. Ashwagandha Root (Withania somnifera): Analytical, quality control, and therapuetic monograph. Santa Cruz, CA: American Herbal Pharmacopoeia 2000:1-25.
  3. Davis L, Kuttan G. Effect of Withania somnifera on cyclophosphamide-induced urotoxicity. Cancer Lett 2000;148:9-17. PubMed
  4. Davis L, Kuttan G. Suppressive effect of cyclophosphamide-induced toxicity by Withania somnifera extract in mice. J Ethnopharmacol 1998;62:209-14. PubMed
  5. Mishra LC, Singh BB, Dagenais S. Scientific basis for the therapeutic use of Withania somnifera (ashwagandha): a review. Altern Med Rev 2000;5:334-46. DOI
  6. Andallu B, Radhika B. Hypoglycemic, diuretic and hypocholesterolemic effect of winter cherry (Withania somnifera, Dunal) root. Indian J Exp Biol 2000;38:607-9.
  7. Kulkarni RR, Patki PS, Jog VP, et al. Treatment of osteoarthritis with a herbomineral formulation: a double-blind, placebo-controlled, cross-over study. J Ethnopharmacol 1991;33:91-5. PubMed
  8. Ahumada F, Aspee F, Wikman G, Hancke J. Withania somnifera exract. Its effects on arterial blood pressure in anaesthetized dogs. Phytother Res 1991;5:111-14.
  9. Panda S, Kar A. Withania somnifera and Bauhinia purpurea in the regulation of circulating thyroid hormone concentrations in female mice. J Ethnopharmacol 1999;67:233-39. PubMed
  10. Panda S, Kar A. Changes in thyroid hormone concentrations after administration of ashwagandha root extract to adult male mice. J Pharm Pharmacol 1998;50:1065-68. PubMed
  11. Sehgal, V. N., Verma, P., and Bhattacharya, S. N. Fixed-drug eruption caused by ashwagandha (Withania somnifera): a widely used Ayurvedic drug. Skinmed. 2012;10(1):48-49.
  12. Agnihotri AP, Sontakke SD, Thawani VR, Saoji A, Goswami VS. Effects of Withania somnifera in patients of schizophrenia: a randomized, double blind, placebo controlled pilot trial study. Indian J Pharmacol. 2013;45(4):417-8. PubMed
  13. Biswal BM, Sulaiman SA, Ismail HC, Zakaria H, Musa KI. Effect of Withania somnifera (Ashwagandha) on the development of chemotherapy-induced fatigue and quality of life in breast cancer patients. Integr Cancer Ther. 2013;12(4):312-22.
  14. Sharma AK, Basu I, Singh S. Efficacy and safety of Ashwagandha root extract in subclinical hypothyroid patients: a double-blind, randomized placebo-controlled trial. J Altern Complement Med. 2018 Mar;24(3):243-248. PubMed
  15. Durg S, Bavage S, Shivaram SB. Withania somnifera (Indian ginseng) in diabetes mellitus: A systematic review and meta-analysis of scientific evidence from experimental research to clinical application. Phytother Res. 2020;34(5):1041-1059.
  16. Björnsson HK, Björnsson ES, Avula B, et al. Ashwagandha-induced liver injury: A case series from Iceland and the US Drug-Induced Liver Injury Network. Liver Int. 2020;40(4):825-829. PubMed
  17. Tharakan A, Shukla H, Benny IR, Tharakan M, George L, Koshy S. Immunomodulatory Effect of Withania somnifera (Ashwagandha) Extract-A Randomized, Double-Blind, Placebo Controlled Trial with an Open Label Extension on Healthy Participants. J Clin Med 2021;1 PubMed
  18. Ireland PJ, Hardy T, Burt AD, Donnelly MC. Drug-induced hepatocellular injury due to herbal supplement ashwagandha. J R Coll Physicians Edinb. 2021;51(4):363-365. PubMed
  19. Kamal HI, Patel K, Brdak A, Heffernan J, Ahmad N. Ashwagandha as a unique cause of thyrotoxicosis presenting with supraventricular tachycardia. Cureus. 2022 Mar 25;14(3):e23494. PubMed
  20. Suryawanshi G, Abdallah M, Thomson M, Desai N, Chauhan A, Lim N. Ashwagandha-Associated Acute Liver Failure Requiring Liver Transplantation. Am J Ther 2023;30(1):e80-e83. PubMed
  21. Pusec CM, Wolsky R, Llerena C, Sura P. A Case of Supplement-Induced Hepatitis. Cureus 2022;14(10):e30433. PubMed
  22. Ajgaonkar A, Jain M, Debnath K. Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract for Improvement of Sexual Health in Healthy Women: A Prospective, Randomized, Placebo-Controlled Study. Cureus 2022;14(10):e30787. PubMed
  23. Haron MH, Dale O, Martin K, et al. Evaluation of the Herb-Drug Interaction Potential of Commonly Used Botanicals on the US Market with Regard to PXR- and AhR-Mediated Influences on CYP3A4 and CYP1A2. J Diet Suppl 2022. PubMed
  24. Lubarska M, Halasinski P, Hryhorowicz S, et al. Liver Dangers of Herbal Products: A Case Report of Ashwagandha-Induced Liver Injury. Int J Environ Res Public Health 2023;20(5):3921. PubMed
  25. Tóth M, Benedek AE, Longerich T, Seitz HK. Ashwagandha-induced acute liver injury: A case report. Clin Case Rep 2023;11(3):e7078.
  26. Bokan G, Glamocanin T, Mavija Z, et al. Herb-Induced Liver Injury by Ayurvedic Ashwagandha as Assessed for Causality by the Updated RUCAM: An Emerging Cause. Pharmaceuticals (Basel) 2023;16(8):1129. PubMed
  27. Patel PA, Sanborn E, Then R, Williams DM. Recurrent Reversible Cerebral Vasoconstriction Syndrome: A Report of Two Cases. Cureus 2023;15(8):e42992. PubMed
  28. Majeed M, Nagabhushanam K, Murali A, Vishwanathan DT, Mamidala RV, Mundkur L. A Standardized Withania somniferra (Linn.) Root Extract with Piperine Alleviates the Symptoms of Anxiety and Depression by Increasing Serotonin Levels: A Double-Blind, Randomize
  29. Philips CA, Valsan A, Theruvath AH, et al. Ashwagandha-induced liver injury-A case series from India and literature review. Hepatol Commun 2023;7(10):e0270. PubMed
  30. Hayashi M, Hamada H, Azuma SI, Hayashi K. Painless Thyroiditis by Withania somnifera (Ashwagandha). Cureus 2024;16(3):e55352. PubMed
  31. Vazirani S, Kothari A, Fujimoto J, Gomez M. Supplements Are Not a Synonym for Safe: Suspected Liver Injury From Ashwagandha. Fed Pract 2023;40(9):315-319. PubMed
  32. Patel M, Newell R, Hillier M, Ramalingam R. Herbal remedies as a potential cause of hypoadrenalism. Br J Hosp Med (Lond) 2024;85(6):1-4. PubMed

See these in context on the Ashwagandha monograph →

Choline 14 references
  1. Yates AA, Schlicker SA, Suitor CW. Dietary reference intakes: The new basis for recommendations for calcium and related nutrients, B vitamins, and choline. J Am Diet Assoc 1998;98:699-706. 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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