Major interaction on record — check this product against your medications before combining. Based on 5 of 6 ingredients. Check your meds →
Dietary supplement

Tokkyo Test 400 Ingredients & Drug Interactions

by Tokkyo Nutrition

Tokkyo Test 400 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 Tokkyo Test 400 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

Tokkyo Test 400 is a dietary supplement by Tokkyo Nutrition with 6 active ingredients. Its ingredients are commonly taken for anxiety and stress, sleep problems, relaxation.Based on those ingredients, 984 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are 1,3, 7-trimethyl-H-purine-2,6(3H, 7H)-dione, 4-Aminobutanoic Acid, 5,7-dihydroxy-2-phenyl-4h-chromen-4-one. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Tokkyo Test 400 by Tokkyo Nutrition

Ask about any prescription or over-the-counter medication and we check it for interactions with Tokkyo Test 400 by Tokkyo Nutrition — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Tokkyo Test 400 by Tokkyo Nutrition

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 Sep 17, 2026

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 0 of its 6 active ingredients.
  • “Proprietary Blend” is a proprietary blend — the label gives one combined amount (150 mg) without saying how much of each component you get.

Tokkyo Test 400 contains 6 active ingredients in a proprietary blend. The key components are GABA (gamma-aminobutyric acid)—a neurotransmitter that plays a role in relaxation—chrysin, a compound from plants; diindolylmethane, a substance derived from cruciferous vegetables like broccoli; caffeine, a stimulant; tribulus, a plant extract; and 5-androsten-3beta-ol-17-one.

The capsule itself is made from gelatin, and the blend includes silica, magnesium stearate, maltodextrose, cellulose, and arginine as inactive ingredients.

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

This product doesn't appear to be marketed for a specific use, so we graded its ingredients' overall clinical evidence instead.

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Neonatal apnea — rated "Effective" (Caffeine) (Natural Medicines).
  • On file: Postoperative headache — rated "Effective" (Caffeine) (Natural Medicines).
  • On file: Athletic performance — rated "Likely Effective" (Caffeine) (Natural Medicines).
  • On file: Mental alertness — rated "Likely Effective" (Caffeine) (Natural Medicines).
  • On file: Sexual dysfunction — rated "Possibly Effective" (Tribulus) (Natural Medicines).

The evidence for most ingredients in this product remains unclear. GABA shows insufficient reliable evidence for anxiety, ADHD, bronchitis, cerebral palsy, and athletic performance.

Chrysin similarly lacks sufficient evidence for anxiety, cancer, HIV/AIDS, muscle strength, gout, and athletic performance. Diindolylmethane has insufficient evidence for prostate health, breast cancer, colorectal cancer, cervical dysplasia, and breast pain.

Tribulus is possibly effective for sexual function but appears possibly ineffective for athletic performance, with insufficient evidence for prostate health. Caffeine is the only ingredient with stronger evidence—it's effective for neonatal apnea and postoperative headache, and likely effective for mental alertness and athletic performance.

The evidence, ingredient by ingredient Gamma-aminobutyric Acid (gaba) Chrysin Diindolylmethane Caffeine Tribulus

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 4 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

GABA is generally well tolerated for short-term use, but long-term safety hasn't been well studied; the most common side effects include drowsiness, nausea, gastric upset, muscle weakness, and minor throat burning. Chrysin is also generally well tolerated short-term, though long-term data are limited.

Diindolylmethane is well tolerated and considered likely safe, with common side effects being diarrhea, gas, headache, nausea, rash, and vomiting. Caffeine in moderate amounts is generally safe for healthy adults but high doses can cause serious effects; common effects are anxiety, insomnia, jitteriness, tremors, and nausea.

Tribulus is well tolerated short-term in healthy adults, though quality and long-term safety data are sparse; uncommon but serious side effects like liver injury, kidney injury, and seizures have been reported. Regarding pregnancy: chrysin and tribulus safety data advise against use during pregnancy; diindolylmethane is considered likely safe; and caffeine carries possibly safe and possibly unsafe ratings—talk with your doctor about safe intake limits.

For breastfeeding: chrysin and tribulus safety data advise against use; diindolylmethane and caffeine data are limited (small amounts of caffeine pass into milk and moderate intake is usually considered acceptable). We hold no pregnancy or breastfeeding data for GABA or 5-androsten-3beta-ol-17-one—ask your doctor or pharmacist for personalized guidance on these.

Side effects, ingredient by ingredient Gamma-aminobutyric Acid (gaba) Chrysin Diindolylmethane Caffeine Tribulus

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?
  • 5 of the 5 matched ingredients can interact with medications — Tribulus, Gamma-aminobutyric Acid (gaba), Caffeine, Chrysin, Diindolylmethane.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; lithium.
  • For scale: 984 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 taking Tokkyo Test 400, double-check with your doctor or pharmacist if you use ephedrine (or any stimulant), blood pressure medications, diabetes drugs, birth control pills or patches, blood thinners like warfarin, diclofenac or other NSAIDs, seizure medications like carbamazepine or phenobarbital, lithium, antipsychotics like clozapine, antidepressants, diuretics (water pills), barbiturates, or dipyridamole. The Major interaction between caffeine and ephedrine carries the highest risk.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with strong clinical evidence behind its ingredients' uses. Major medication interactions have been identified, and safety information is well characterized.

This is a multi-ingredient supplement with significant medication interactions across blood pressure drugs, diabetes medications, birth control, blood thinners, seizure medications, antipsychotics, and several others—the caffeine–ephedrine combination is particularly serious. Most ingredients lack solid evidence for their claimed uses.

If you take any regular medications, check each one against our search tool before starting. Discuss this product with your doctor or pharmacist, especially if you're pregnant, breastfeeding, or manage a chronic condition.

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

Assessment coverage: 5 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Apr 25, 2014.

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 Tokkyo Test 400, straight from the product label.

Brand Tokkyo Nutrition
Barcode (UPC) 896896002552
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Apr 25, 2014
DSLD ID 16514
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult Male (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 Tokkyo Test 400 by Tokkyo Nutrition, 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
60
UPC/BARCODE
896896002552
IngredientAmount% DV
Proprietary Blend150 mg--
4-Aminobutanoic Acid0 NP--
5,7-dihydroxy-2-phenyl-4h-chromen-4-one0 NP--
5-Androsten-3Beta-Ol-17-One0 NP--
3-(1H-Indol-3-ylmethyl)-1H-indole0 NP--
1,3, 7-trimethyl-H-purine-2,6(3H, 7H)-dione0 NP--
Tribulus extract0 NP--

Other ingredients: Gelatin, Silica, Magnesium Stearate, Maltodextrose, Cellulose, Arginine

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.
Suggested/Recommended/Usage/Directions

As a dietary supplement take (1) one capsules in the morning and (1) one capsules in the afternoon. For maximum absorption, take this supplement with at least 15 grams of fat. It is recommended that you take Tokkyo Liver-900 for the duration of this supplement, and take Tokkyo Letro-Z for at least two weeks after discontinuing use of this supplement.

This product is only intended to be consumed by healthy adult males 18 years of age or older.

Precautions

Warning: CONSULT YOUR PHYSICIAN BEFORE USING THIS PRODUCT.

Warning: NOT FOR WOMEN OR INDIVIDUALS UNDER THE AGE OF 18 YEARS.

Consult a physician or licensed qualified health care professional before using this product if you have any pre-existing medical condition including but not limited to: high or low blood pressure, cardiac arrhythmia, anxiety, depression, stroke, heart, liver, kidney or thyroid disease, seizure disorder, psychiatric disease, diabetes, prostate cancer, prostate enlargement, low "good" cholesterol (HDL), any other medical condition or if you are using any other dietary supplements, prescription drug, or over-the-counter drug. Do not exceed recommended serving. Exceeding recommended serving may cause serious adverse health effects. Possible side effects include acne, hair loss, hair growth on the face (in women) aggressiveness, irritability, and increased levels of estrogen. Discontinue use and call a physician or licensed qualified health care professional immediately if you experience rapid heartbeat, dizziness, blurred vision, or other similar symptoms.

Allergen Warning: manufactured on equipment which processes products containing milk, eggs, soybeans, fish oil, tree nuts, and peanut butter flavor.

Note: If you are a professional or amateur athlete subject to performance enhancing substances testing, do not use this product unless cleared by your sanctioning body as it may cause a false reactive result for a urine or blood drug test.

Real all label information and warnings. Do not exceed recommended dosage.

Keep out of reach of children.

General Statements

To report any adverse events call 1-800-332-1088.

CAUTION CAUTION CAUTION MUSCLE ACTIVATOR*

UNDERGROUND SERIES

Pro Testosterone* Build Muscle* Increase Strength* Increase Vascularity*

Advanced Japanese technology has influenced the formulation of the new Tokkyo Nutrition Underground Series in order to maximize every user's results. Utilizing the highest quality ingredients, Tokkyo Nutrition has made industry advancements with this specifically designed new line of products guaranteed to blow away expectations. Pumped. Rugged. Energized. Underground.

FDA Statement of Identity

DIETARY SUPPLEMENT

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.

Storage

Store in a cool, dry place away from sunlight. Always keep tightly sealed.

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

See for yourself

Tokkyo Test 400 by Tokkyo Nutrition label

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

Tokkyo Test 400 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 Tokkyo Test 400 by Tokkyo Nutrition

These are the 6 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 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.

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

Interaction report

Tokkyo Test 400 by Tokkyo Nutrition Drug Interactions

Want to check YOUR meds against Tokkyo Test 400?

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
984Drugs
8 Major 678 Moderate 298 Minor

Ingredients driving the most interactions

1,3, 7-trimethyl-H-purine-2,6(3H, 7H)-dione 655
4-Aminobutanoic Acid 419
5,7-dihydroxy-2-phenyl-4h-chromen-4-one 358
3-(1H-Indol-3-ylmethyl)-1H-indole 269
Tribulus extract 259

Individual Drug Interactions

The ingredients in Tokkyo Test 400 interact with 984 drugs. Click any drug to see the details.

5 of the 6 ingredients in Tokkyo Test 400 interact with drugs. Each result below shows which ingredient is responsible. 1,3, 7-trimethyl-H-purine-2,6(3H, 7H)-dione 4-Aminobutanoic Acid 5,7-dihydroxy-2-phenyl-4h-chromen-4-one 3-(1H-Indol-3-ylmethyl)-1H-indole Tribulus extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Tokkyo Test 400 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.

1,3, 7-trimethyl-H-purine-2,6(3H, 7H)-dione41 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
1,3, 7-trimethyl-H-purine-2,6(3H, 7H)-dione full monograph & all 41 interactions

4-Aminobutanoic Acid2 drug types · 419 drugs

Antihypertensive Drugs

Theoretically, taking GABA with antihypertensive drugs might increase the risk of hypotension.
Some clinical research shows that GABA can decrease blood pressure in patients with hypertension.

Likelihood Possible Evidence B
Cns Depressants

Theoretically, GABA might have additive sedative effects when used in conjunction with CNS depressants. However, it is unclear if this concern is clinically relevant.
Endogenous GABA has well-established relaxant effects and GABA(A) receptors have an established physiological role in sleep. However, the effects of GABA supplements are unclear, as it is unknown whether exogenous GABA crosses the blood-brain barrier. Although there have been limited reports of drowsiness or tiredness with GABA supplements, these effects have not been widely reported in clinical studies. Additionally, intravenous GABA 0.1-1 mg/kg has been shown to induce anxiety in a dose-dependent manner.

Likelihood Unlikely Evidence D
4-Aminobutanoic Acid full monograph & interactions

5,7-dihydroxy-2-phenyl-4h-chromen-4-one9 drug types · 358 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, chrysin might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
In vitro evidence suggests that chrysin might inhibit platelet aggregation.

Likelihood Possible Evidence D
Aromatase Inhibitors

Theoretically, chrysin might increase the effects and adverse effects of aromatase inhibitors.
In vitro research suggests that chrysin might decrease estrogen synthesis by acting as an aromatase (estrogen synthetase) inhibitor..

Likelihood Possible Evidence D
Contraceptive Drugs

Theoretically, chrysin might reduce the efficacy of estrogen-containing contraceptive drugs.
In vitro research suggests that chrysin might have antiestrogenic activity.

Likelihood Possible Evidence D
Diclofenac (Voltaren, Others)

Theoretically, chrysin might increase the effects and adverse effects of diclofenac.
In vitro research suggests that chrysin and its sulfate conjugate inhibit diclofenac metabolism. It is speculated that chrysin and its sulfate conjugate reduce the metabolism of diclofenac by inhibiting cytochrome P450 2C9. This effect has not been reported in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, chrysin might decrease the effects of estrogen therapy.
In vitro research suggests that chrysin might have antiestrogenic activity.

Likelihood Possible Evidence D
Mephenytoin (Mesantoin)

Theoretically, chrysin might increase the effects and adverse effects of mephenytoin.
In vitro research suggests that chrysin and its sulfate and glucuronide conjugates inhibit S-mephenytoin metabolism. It is speculated that chrysin and its conjugates reduce the metabolism of S-mephenytoin by inhibiting cytochrome P450 2C19. This effect has not been reported in humans.

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

Theoretically, chrysin might increase levels of drugs metabolized by CYP1A2.
In vitro research suggests that chrysin inhibits CYP1A2 isozymes. However, chrysin does not appear to inhibit CYP1A2-dependent caffeine metabolism in animals. Due to chrysin's low bioavailability and rapid metabolism to glucuronide and sulfate conjugates, this interaction is unlikely.

Likelihood Unlikely Evidence D
Glucuronidated Drugs

Theoretically, chrysin might increase the clearance of drugs that are UGT1A1 substrates, thereby reducing their effectiveness.
In vitro research suggests that chrysin might induce UDP-glucuronosyltransferase 1A1 (UGT1A1).

Likelihood Unlikely Evidence D
Testosterone

Theoretically, chrysin might increase the effects and adverse effects of testosterone.
In vitro research suggests that chrysin and its sulfate conjugate inhibit testosterone metabolism. It is speculated that chrysin and its sulfate conjugate reduce the metabolism of testosterone by inhibiting cytochrome P450 3A4. This effect has not been reported in humans.

Likelihood Possible Evidence D
5,7-dihydroxy-2-phenyl-4h-chromen-4-one full monograph & interactions

3-(1H-Indol-3-ylmethyl)-1H-indole3 drug types · 269 drugs

Diuretic Drugs

Theoretically, diindolylmethane might increase the risk of hyponatremia if used with sodium-depleting diuretics.
Large doses of diindolylmethane (600 mg daily) have been associated with two cases of asymptomatic hyponatremia in clinical research.

Likelihood Possible Evidence B
Estrogens

Theoretically, diindolylmethane might increase or decrease the effects of estrogens.
Diindolylmethane might have mild estrogenic or antiestrogenic effects. Theoretically, large amounts of diindolylmethane might interfere with hormone replacement therapy.

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

Theoretically, diindolylmethane might lower serum levels of CYP1A2 substrates.
In vitro evidence suggests that diindolylmethane can induce CYP1A2. Theoretically, it might increase metabolism of CYP1A2 substrates and lower serum concentrations. This interaction has not been reported in humans.

Likelihood Unlikely Evidence D
3-(1H-Indol-3-ylmethyl)-1H-indole full monograph & interactions

Tribulus extract3 drug types · 259 drugs

Antidiabetes Drugs

Taking tribulus with antidiabetes drugs might increase the risk of hypoglycemia.
Clinical research shows that Tribulus can lower blood glucose levels in adults with type 2 diabetes who are taking antidiabetes medications.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, taking tribulus with antihypertensive drugs might increase the risk of hypotension.
Animal research shows that tribulus can lower blood pressure by inhibiting angiotensin-converting enzyme (ACE). Tribulus has also demonstrated hypotensive effects in pre-hypertensive adults.

Likelihood Possible Evidence D
Lithium

Theoretically, tribulus might increase the levels and clinical effects of lithium.
Tribulus is thought to have diuretic properties. Due to these potential diuretic effects, tribulus might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

Likelihood Probable Evidence D
Tribulus extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Tokkyo Test 400, from the product label.

Tokkyo Nutrition

See all Tokkyo Nutrition products
Name
FPL Wholesalers, LLC
Street Address
P.O. Box 10696
City
Bedford
State
NH
ZipCode
03110
Phone Number
1-866-320-0141
Web Address
www.tokkyonutrition.com
Pharmacist Counseling Corner

Tokkyo Test 400 by Tokkyo Nutrition: Common Questions

Does Tokkyo Test 400 by Tokkyo Nutrition interact with any medications?
Yes. Based on its ingredients, Tokkyo Test 400 has a known interaction with 984 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?
Tokkyo Test 400 contains 6 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.
Does this product interact with blood pressure medications?
Yes—both GABA and tribulus can theoretically increase the risk of low blood pressure (hypotension) when taken with blood pressure drugs. This is a Moderate concern, so check your specific medications with your doctor or pharmacist before starting.
Can I take this if I'm on birth control?
Chrysin in this product may theoretically reduce the effectiveness of estrogen-containing contraceptives. This is a Moderate interaction, so discuss it with your doctor or pharmacist to make sure your birth control remains reliable.
Is it safe to take while breastfeeding?
Chrysin and tribulus data advise against use while breastfeeding. Diindolylmethane is considered likely safe, and small amounts of caffeine pass into milk—moderate caffeine intake is usually acceptable but can affect the baby. There isn't enough data on GABA or the other ingredient for us to advise either way, so talk with your doctor or pharmacist for personalized guidance.
What are the most common side effects?
GABA may cause drowsiness, nausea, or gastric upset. Diindolylmethane commonly causes diarrhea, gas, headache, or nausea. Caffeine often causes anxiety, insomnia, jitteriness, and restlessness, especially at higher doses.
Does this supplement have solid evidence that it works?
Most ingredients lack sufficient evidence to rate their effectiveness for their intended uses. Caffeine is the exception—it's proven effective for mental alertness and athletic performance. The other ingredients show insufficient evidence or mixed results.
Can I take this with my diabetes medications?
Tribulus in this product may lower blood sugar, and taking it with diabetes drugs could theoretically increase the risk of low blood sugar (hypoglycemia). Check with your doctor or pharmacist about whether this combination is safe for you.

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.

Tokkyo Test 400 label
Go deeper

The Full Monographs Behind Tokkyo Test 400’s Ingredients

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

Herb & supplement monograph

Gamma-aminobutyric Acid (gaba)

Interacts with 419 drugs

GABA is a calming chemical messenger (neurotransmitter) that your body makes on its own, and it is sold as a supplement for stress, anxiety, and sleep. The science behind oral GABA supplemen...

Read the full Gamma-aminobutyric Acid (gaba) monograph → Herb & supplement monograph

Chrysin

Interacts with 358 drugs

Chrysin is a plant flavonoid sold mainly as a bodybuilding supplement claimed to raise testosterone or block estrogen, but human studies have not shown these benefits, largely because the bo...

Read the full Chrysin monograph → Herb & supplement monograph

Diindolylmethane

Interacts with 269 drugs

Diindolylmethane (DIM) is a compound made when your body digests cruciferous vegetables, and it is sold as a supplement mainly for hormone balance and cancer prevention. Although early lab s...

Read the full Diindolylmethane 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

Tribulus

Interacts with 259 drugs

Tribulus is a plant supplement most often marketed to boost libido, testosterone, and athletic performance, but the human evidence behind these claims is weak and inconsistent. It is general...

Read the full Tribulus monograph →
Sources

Sources & How We Checked

Tokkyo Test 400'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 295 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.

Gamma-aminobutyric Acid (gaba) 12 references
  1. Cavagnini F, Invitti C, Pinto M, et al. Effect of acute and repeated administration of gamma aminobutyric acid (GABA) on growth hormone and prolactin secretion in man. Acta Endocrinol (Copenh) 1980;93:149-54.
  2. Nurnberger JI Jr, Berrettini WH, Simmons-Alling S, et al. Intravenous GABA administration is anxiogenic in man. Psychiatry Res 1986;19:113-7. PubMed
  3. Gershman RN, Vasilenko MA, Iliushina GG, et al. [Gammalon in the rehabilitation in infantile cerebral palsy]. Pediatr.Akus.Ginekol. 1977;(6):26-7.
  4. Loeb C, Benassi E, Bo, GP, et al. Preliminary evaluation of the effect of GABA and phosphatidylserine in epileptic patients. Epilepsy Res. 1987;1:209-12 . PubMed
  5. Inoue K, Shirai T, Ochiai H, et al. Blood-pressure-lowering effect of a novel fermented milk containing gamma-aminobutyric acid (GABA) in mild hypertensives. Eur J Clin Nutr 2003;57:490-95.
  6. ELLIOTT, K. A. and JASPER, H. H. Gammaaminobutyric acid. Physiol Rev. 1959;39(2):383-406.
  7. Winsky-Sommerer, R. Role of GABAA receptors in the physiology and pharmacology of sleep. Eur.J.Neurosci. 2009;29(9):1779-1794.
  8. Meldrum, B. S. GABAergic mechanisms in the pathogenesis and treatment of epilepsy. Br.J.Clin.Pharmacol. 1989;27 Suppl 1:3S-11S. PubMed
  9. Loeb, C., Marinari, U. M., Benassi, E., Besio, G., Cottalasso, D., Cupello, A., Maffini, M., Mainardi, P., Pronzato, M. A., and Scotto, P. A. Phosphatidylserine increases in vivo the synaptosomal uptake of exogenous GABA in rats. Exp.Neurol. 1988;99(2):4 PubMed
  10. Melis, G. B., Paoletti, A. M., Mais, V., and Fioretti, P. Interference of dopamine infusion on gamma-amino butyric acid (GABA)-stimulated prolactin increase. J.Endocrinol.Invest 1980;3(4):445-448.
  11. Boonstra E, de Kleijn R, Colzato LS, Alkemade A, Forstmann BU, Nieuwenhuis S. Neurotransmitters as food supplements: the effects of GABA on brain and behavior. Front Psychol. 2015 Oct 6;6:1520. doi: 10.3389/fpsyg.2015.01520. eCollection 2015. PubMed
  12. de Bie TH, Witkamp RF, Balvers MG, Jongsma MA. Effects of ?-aminobutyric acid supplementation on glucose control in adults with prediabetes: A double-blind, randomized, placebo-controlled trial. Am J Clin Nutr 2023;118(3):708-719. PubMed

See these in context on the Gamma-aminobutyric Acid (gaba) monograph →

Chrysin 23 references
  1. Galijatovic A, Otake Y, Walle UK, Walle T. Extensive metabolism of the flavonoid chrysin by human Caco-2 and Hep G2 cells. Xenobiotica 1999;29:1241-56. PubMed
  2. Lee H, Yeom H, Kim YG, et al. Structure-related inhibition of human hepatic caffeine N3-demethylation by naturally occurring flavonoids. Biochem Pharmacol 1998;55:1369-75. PubMed
  3. Galijatovic A, Walle UK, Walle T. Induction of UDP-glucuronosyltransferase by the flavonoids chrysin and quercetin in Caco-2 cells. Pharm Res 2000;17:21-6.
  4. Walle UK, Galijatovic A, Walle T. Transport of the flavonoid chrysin and its conjugated metabolites by the human intestinal cell line Caco-2. Biochem Pharmacol 1999;58:431-8. PubMed
  5. Kao YC, Zhou C, Sherman M, et al. Molecular basis of the inhibition of human aromatase (estrogen synthetase) by flavone and isoflavone phytoestrogens: A site-directed mutagenesis study. Environ Health Perspect 1998;106:85-92. PubMed
  6. Jeong HJ, Shin YG, Kim IH, Pezzuto JM. Inhibition of aromatase activity by flavonoids. Arch Pharm Res 1999;22:309-12. PubMed
  7. Walle T, Otake Y, Galijatovic A, et al. Induction of UDP-glucuronosyltransferase UGT1A1 by the flavonoid chrysin in the human hepatoma cell line hep G2. Drug Metab Dispos 2000;28:1077-82. DOI
  8. Walle T, Otake Y, Brubaker JA, et al. Disposition and metabolism of the flavonoid chrysin in normal volunteers. Br J Clin Pharmacol 2001;51:143-6. DOI
  9. Galijatovic A, Otake Y, Walle UK, Walle T. Induction of UDP-glucuronosyltransferase UGT1A1 by the flavonoid chrysin in Caco-2 cells--potential role in carcinogen bioinactivation. Pharm Res 2001;18:374-9. PubMed
  10. Lautraite S, Musonda AC, Doehmer J, et al. Flavonoids inhibit genetic toxicity produced by carcinogens in cells expressing CYP1A2 and CYP1A1. Mutagenesis 2002;17:45-53. PubMed
  11. Han, D. H., Denison, M. S., Tachibana, H., and Yamada, K. Relationship between estrogen receptor-binding and estrogenic activities of environmental estrogens and suppression by flavonoids. Biosci.Biotechnol.Biochem 2002;66(7):1479-1487. PubMed
  12. O'Leary, K. A., de Pascual-Tereasa, S., Needs, P. W., Bao, Y. P., O'Brien, N. M., and Williamson, G. Effect of flavonoids and vitamin E on cyclooxygenase-2 (COX-2) transcription. Mutat.Res 7-13-2004;551(1-2):245-254. PubMed
  13. Woodman, O. L. and Chan, E. C. Vascular and anti-oxidant actions of flavonols and flavones. Clin Exp Pharmacol Physiol 2004;31(11):786-790. PubMed
  14. Simons, A. L., Renouf, M., Hendrich, S., and Murphy, P. A. Human gut microbial degradation of flavonoids: structure-function relationships. J Agric.Food Chem 5-18-2005;53(10):4258-4263. PubMed
  15. Kim, H. J., Lee, S. B., Park, S. K., Kim, H. M., Park, Y. I., and Dong, M. S. Effects of hydroxyl group numbers on the B-ring of 5,7-dihydroxyflavones on the differential inhibition of human CYP 1A and CYP1B1 enzymes. Arch Pharm Res 2005;28(10):1114-1121 PubMed
  16. Moon, Y. J., Wang, X., and Morris, M. E. Dietary flavonoids: effects on xenobiotic and carcinogen metabolism. Toxicol In Vitro 2006;20(2):187-210. PubMed
  17. Landolfi, R., Mower, R. L., and Steiner, M. Modification of platelet function and arachidonic acid metabolism by bioflavonoids. Structure-activity relations. Biochem Pharmacol 5-1-1984;33(9):1525-1530. PubMed
  18. Tsyrlov, I. B., Mikhailenko, V. M., and Gelboin, H. V. Isozyme- and species-specific susceptibility of cDNA-expressed CYP1A P-450s to different flavonoids. Biochim.Biophys Acta 4-13-1994;1205(2):325-335. PubMed
  19. Collins, B. M., McLachlan, J. A., and Arnold, S. F. The estrogenic and antiestrogenic activities of phytochemicals with the human estrogen receptor expressed in yeast. Steroids 1997;62(4):365-372. PubMed
  20. Kuiper, G. G., Lemmen, J. G., Carlsson, B., Corton, J. C., Safe, S. H., van der Saag, P. T., van der Burg, B., and Gustafsson, J. A. Interaction of estrogenic chemicals and phytoestrogens with estrogen receptor beta. Endocrinology 1998;139(10):4252-4263. PubMed
  21. Liu G, Xie W, He AD, et al. Antiplatelet activity of chrysin via inhibiting platelet aIIbß3-mediated signaling pathway. Mol Nutr Food Res 2016;60(9):1984-93.
  22. Noh K, Oh do G, Nepal MR, et al. Pharmacokinetic interaction of chrysin with caffeine in rats. Biomol Ther (Seoul) 2016;24(4):446-52. PubMed
  23. Mohos V, Fliszár-Nyúl E, Ungvári O, et al. Effects of Chrysin and Its Major Conjugated Metabolites Chrysin-7-Sulfate and Chrysin-7-Glucuronide on Cytochrome P450 Enzymes and on OATP, P-gp, BCRP, and MRP2 Transporters. Drug Metab Dispos 2020;48(10):1064-10 PubMed

See these in context on the Chrysin monograph →

Diindolylmethane 14 references
  1. Natl Inst Health, Natl Inst Environmental Health Sci. Indole-3-carbinol. Available at: http://ntp-server.niehs.nih.gov.
  2. Balk JL. Indole-3-carbinol for cancer prevention. Altern Med Alert 2000; 3:105-7.
  3. Riby JE, Chang GHF, Firestone GL, Bjeldanes LF. Ligand-independent activation of estrogen receptor function by 3,3'-diindolylmethane in human breast cancer cells. Biochem Pharmacol 2000;60:167-77. PubMed
  4. Lake BG, Tredger JM, Renwick AB, et al. 3'3-diindolylmethane induces CYP1A2 in cultured precision-cut human liver slices. Xenobiotica 1998;28:803-11. PubMed
  5. Dalessandri, K. M., Firestone, G. L., Fitch, M. D., Bradlow, H. L., and Bjeldanes, L. F. Pilot study: effect of 3,3'-diindolylmethane supplements on urinary hormone metabolites in postmenopausal women with a history of early-stage breast cancer. Nutr Canc PubMed
  6. Reed, G. A., Arneson, D. W., Putnam, W. C., Smith, H. J., Gray, J. C., Sullivan, D. K., Mayo, M. S., Crowell, J. A., and Hurwitz, A. Single-dose and multiple-dose administration of indole-3-carbinol to women: pharmacokinetics based on 3,3'-diindolylmetha
  7. Reed, G. A., Sunega, J. M., Sullivan, D. K., Gray, J. C., Mayo, M. S., Crowell, J. A., and Hurwitz, A. Single-dose pharmacokinetics and tolerability of absorption-enhanced 3,3'-diindolylmethane in healthy subjects. Cancer Epidemiol.Biomarkers Prev. 2008; PubMed
  8. Del Priore G., Gudipudi, D. K., Montemarano, N., Restivo, A. M., Malanowska-Stega, J., and Arslan, A. A. Oral diindolylmethane (DIM): pilot evaluation of a nonsurgical treatment for cervical dysplasia. Gynecol.Oncol. 2010;116(3):464-467. PubMed
  9. Heath, E. I., Heilbrun, L. K., Li, J., Vaishampayan, U., Harper, F., Pemberton, P., and Sarkar, F. H. A phase I dose-escalation study of oral BR-DIM (BioResponse 3,3'- Diindolylmethane) in castrate-resistant, non-metastatic prostate cancer. Am.J.Transl.R
  10. Jellinck, P. H., Forkert, P. G., Riddick, D. S., Okey, A. B., Michnovicz, J. J., and Bradlow, H. L. Ah receptor binding properties of indole carbinols and induction of hepatic estradiol hydroxylation. Biochem.Pharmacol. 3-9-1993;45(5):1129-1136. PubMed
  11. Bui PV, Moualla M, Upson DJ. A Possible Association of Diindolylmethane with Pulmonary Embolism and Deep Venous Thrombosis. Case Rep Med. 2016;2016:7527098. PubMed
  12. Castañon A, Tristram A, Mesher D, Powell N, Beer H, Ashman S, Rieck G, Fielder H, Fiander A, Sasieni P. Effect of diindolylmethane supplementation on low-grade cervical cytological abnormalities: double-blind, randomised, controlled trial. Br J Cancer. 20 PubMed
  13. Le TM, Sanders CJ, van de Corput L, van Erpecum KJ, Röckmann H. Drug rash with eosinophilia and systemic symptoms caused by the dietary supplement diindolylmethane. J Allergy Clin Immunol Pract. 2016 Jan-Feb;4(1):175-6. PubMed
  14. Pence ST, Mehta K, Crum-Bailey J. The Serious Side of Supplements: An Ischemic Stroke in a Healthy 38-year-old Female. Mil Med 2022. PubMed

See these in context on the Diindolylmethane monograph →

Caffeine 236 references
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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.

© 2021 Therapeutic Research Center, LLC

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