Interactions on record — worth a quick check against your medications. Based on 4 of 6 ingredients. Check your meds →
Dietary supplement

Neuro-5-HTP Plus Ingredients & Drug Interactions

by Biotics Research Corporation

Neuro-5-HTP Plus label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Neuro-5-HTP Plus 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: Moderate

Neuro-5-HTP Plus is a dietary supplement by Biotics Research Corporation with 6 active ingredients. Its ingredients are commonly taken for anxiety and stress, relaxation and calm, sleep support.Based on those ingredients, 1,045 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Niacin, L-Theanine, L-5-Hydroxytryptophan. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Neuro-5-HTP Plus by Biotics Research Corporation

Ask about any prescription or over-the-counter medication and we check it for interactions with Neuro-5-HTP Plus by Biotics Research Corporation — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Neuro-5-HTP Plus by Biotics Research Corporation

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

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 27, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 6 of its 6 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Neuro-5-HTP Plus contains 6 active and inactive ingredients. The active components are L-theanine (an amino acid from tea that may support calm focus), niacin (vitamin B3, essential for energy and cell function), L-5-hydroxytryptophan (5-HTP, a precursor to serotonin), superoxide dismutase and catalase (enzymes), and vitamin B6 (pyridoxine, vital for brain and nervous system function).

The remaining ingredients—gelatin, water, and glycerin—are inactive and serve as the capsule material and carrier.

Does it work?

Moderate 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
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: mood, anxiety, sleep, and migraine support.
  • We looked for evidence on: Anxiety, Depression, Generalized anxiety disorder (GAD), Insomnia, Migraine headache, Panic disorder — and 4 related terms.
  • The strongest evidence on file: 5-htp is rated "Possibly Effective" for Depression (Natural Medicines).
  • Also on file: 5-htp is rated "Insufficient Reliable Evidence To Rate" for Anxiety, Migraine headache, Fibromyalgia, Insomnia, and more.
  • Also on file: Niacin is rated "Insufficient Reliable Evidence To Rate" for Migraine headache.

L-theanine is possibly effective for cognitive function but lacks reliable evidence for age-related cognitive decline, Alzheimer's disease, or anxiety disorders. Niacin is likely effective for pellagra (a niacin-deficiency disease) and possibly effective for certain lipid disorders and metabolic syndrome.

L-5-hydroxytryptophan is possibly effective for depression but appears possibly ineffective for Down syndrome and lacks reliable evidence for Alzheimer's disease, panic disorder, or cerebellar ataxia. Vitamin B6 is effective for sideroblastic anemia and vitamin B6 deficiency, likely effective for elevated homocysteine, and possibly effective for pregnancy-related nausea.

We hold no effectiveness data for superoxide dismutase or catalase.

The evidence, ingredient by ingredient Theanine Niacin 5-htp Vitamin B6

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

L-theanine is generally well tolerated for short-term use in healthy adults, though long-term safety isn't well studied; reported side effects include headaches, drowsiness, and increased dream activity. It should be avoided in pregnancy and while breastfeeding due to insufficient safety data.

Niacin is safe at normal dietary amounts and in prescription doses when monitored, but high supplemental doses can cause flushing (affecting up to 70% of users), stomach upset, liver problems, and rarely serious effects like muscle breakdown; normal amounts in prenatal vitamins are fine, but high-dose niacin should be prescribed. L-5-hydroxytryptophan is generally well tolerated short-term but should be avoided in pregnancy and while breastfeeding; common side effects include nausea, diarrhea, dizziness, headache, and drowsiness, with rare serious effects like mania or hallucinations at high doses.

Vitamin B6 is safe at normal dietary amounts and standard supplements, but high doses over time can damage nerves (sensory neuropathy); standard doses are generally acceptable during breastfeeding and pregnancy-related nausea under medical supervision, though some evidence raises questions about very high intake and cancer risk.

Side effects, ingredient by ingredient Theanine Niacin 5-htp Vitamin B6

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 4 of the 4 matched ingredients can interact with medications — 5-htp, Niacin, Vitamin B6, Theanine.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; Parkinson's medications.
  • For scale: 1,046 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 Neuro-5-HTP Plus, double-check with your own pharmacist or doctor if you take blood thinners or antiplatelet drugs (niacin raises bleeding risk—Moderate), blood pressure medications (L-theanine, niacin, and vitamin B6 may lower pressure further—Moderate), sedating drugs like sleep aids or opioids (5-HTP and L-theanine may add sedation—Moderate/Minor), antidepressants or other serotonin-affecting medications (5-HTP and L-theanine may intensify serotonin effects—Moderate/Minor), diabetes medications (niacin can raise blood sugar—Moderate), seizure drugs like phenobarbital or phenytoin (high-dose B6 may reduce their effectiveness—Moderate), the heart drug amiodarone (B6 may worsen sun sensitivity—Moderate), statins for cholesterol (niacin may raise muscle-breakdown risk—Moderate), or gout medications like allopurinol (niacin may interfere—Moderate). These are the medication types our data shows warrant a conversation before you start.

Check your own medication Run your meds through the checker above

The bottom line

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

This product may appeal to someone looking for support with mood, cognition, or energy—niacin covers an essential nutrient, and 5-HTP and L-theanine address serotonin and calm focus. However, if you take blood pressure medications, blood thinners, diabetes drugs, seizure medications, or statins, you'll need to review your specific medications with your own doctor or pharmacist before starting.

The same goes if you're pregnant or breastfeeding—L-theanine, 5-HTP, and niacin have individual safety considerations you should discuss. Talk it over with your healthcare provider to make sure it's right for you.

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

Assessment coverage: 4 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 25, 2013.

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 Neuro-5-HTP Plus, straight from the product label.

Brand Biotics Research Corporation
Net contents 90 Capsule(s)
Market status On market
Date entered into DSLD Jun 25, 2013
DSLD ID 22112
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Neuro-5-HTP Plus by Biotics Research Corporation, 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)
IngredientAmount% DV
L-Theanine50 mg--
Niacin50 mg250%
L-5-Hydroxytryptophan50 mg--
Superoxide Dismutase50 mcg--
Catalase50 mcg--
Vitamin B610 mg500%

Other ingredients: Gelatin, Water, Glycerin

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

RECOMMENDATION: One (1) capsule taken two (2) times each day as a dietary supplement or as otherwise directed by a healthcare professional.

Precautions

Caution: Not recommended for pregnant or lactating women.

KEEP OUT OF REACH OF CHILDREN

Sealed with an imprinted safety seal for your protection.

Storage

Store in a cool, dry area.

General

Rev. 8/08

FDA Statement of Identity

Dietary Supplement

General Statements

Specially grown, biologically active containing naturally associated and/or organically bound phytochemicals including polyphenolic compounds with SOD and catalase, dehydrated at low temperature to preserve associated enzyme factors.

Brand IP Statement(s)

(C) Copyright 2010

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

See for yourself

Neuro-5-HTP Plus by Biotics Research Corporation label

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

Neuro-5-HTP Plus 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 Neuro-5-HTP Plus by Biotics Research Corporation

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

Serving size1 Capsule(s) Dosage formCapsule 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.

L-Theanine

Interacts with
565 drugs
50 mg per serving

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

L-Theanine monograph & interactions

Niacin

Interacts with
727 drugs
50 mg per serving Form: Niacinamide

Niacin (vitamin B3) is an essential nutrient your body needs for energy and metabolism, and deficiency is uncommon in most developed countries. Prescr...

Niacin monograph & interactions

L-5-Hydroxytryptophan

Interacts with
398 drugs
50 mg per serving

5-HTP is a compound your body uses to make serotonin, and people take it as a supplement hoping to improve mood, sleep, and headaches. Some early rese...

L-5-Hydroxytryptophan monograph & interactions

Superoxide Dismutase

50 mcg per serving

Catalase

50 mcg per serving

Vitamin B6

Interacts with
210 drugs
10 mg per serving Form: Pyridoxal 5-Phosphate

Vitamin B6 (pyridoxine) is an essential water-soluble vitamin that your body needs for metabolism, brain function, and making red blood cells. It is b...

Vitamin B6 monograph & interactions

Other (inactive) ingredients: Gelatin, Water, Glycerin. These complete the product’s ingredient list but are not active constituents.

Interaction report

Neuro-5-HTP Plus by Biotics Research Corporation Drug Interactions

Want to check YOUR meds against Neuro-5-HTP Plus?

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
1,045Drugs
1,043 Moderate 2 Minor

Ingredients driving the most interactions

Niacin 727
L-Theanine 565
L-5-Hydroxytryptophan 398
Vitamin B6 210

Individual Drug Interactions

The ingredients in Neuro-5-HTP Plus interact with 1,045 drugs. Click any drug to see the details.

4 of the 6 ingredients in Neuro-5-HTP Plus interact with drugs. Each result below shows which ingredient is responsible. Niacin L-Theanine L-5-Hydroxytryptophan Vitamin B6

Each ingredient & the kinds of drugs it affects

For each ingredient in Neuro-5-HTP Plus 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.

Niacin15 drug types · 727 drugs

Alcohol (Ethanol)

Concomitant use of alcohol and niacin might increase the risk of flushing and hepatotoxicity.
Alcohol can exacerbate the flushing and pruritus associated with niacin. Large doses of niacin might also exacerbate liver dysfunction associated with chronic alcohol use. A case report describes delirium and lactic acidosis in a patient taking niacin 3 grams daily who ingested 1 liter of wine. Advise patients to avoid large amounts of alcohol while taking niacin.

Likelihood Probable Evidence D
Allopurinol (Zyloprim)

Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as allopurinol.
Large doses of niacin can reduce urinary excretion of uric acid, potentially resulting in hyperuricemia. Doses of uricosurics such as allopurinol might need to be increased to maintain control of gout in patients who start taking niacin. People who have frequent attacks of gout despite uricosuric therapy should avoid niacin.

Likelihood Probable Evidence C
Anticoagulant/Antiplatelet Drugs

Theoretically, niacin may have additive effects when used with anticoagulant or antiplatelet drugs.
Several cases of clotting factor synthesis deficiency and coagulopathy have been reported in patients taking sustained-release niacin. Also, thrombocytopenia has been reported in patients treated with niacin or niacin plus lovastatin.

Likelihood Possible Evidence D
Antidiabetes Drugs

Niacin can increase blood glucose levels and may diminish the effects of antidiabetes drugs.
Niacin impairs glucose tolerance in a dose-dependent manner, probably by causing or aggravating insulin resistance and increasing hepatic production of glucose. In diabetes patients, niacin 4.5 grams daily for 5 weeks can increase plasma glucose by an average of 16% and glycated hemoglobin (HbA1c) by 21%. However, lower doses of 1.5 grams daily or less appear to have minimal effects on blood glucose. In some patients, glucose levels increase when niacin is started, but then return to baseline when a stable dose is reached. Up to 35% of patients with diabetes may need adjustments in hypoglycemic therapy when niacin is added.

Likelihood Probable Evidence B
Antihypertensive Drugs

Theoretically, niacin may increase the risk of hypotension when used with antihypertensive drugs.
The vasodilating effects of niacin can cause hypotension. Furthermore, some clinical evidence suggests that a one-hour infusion of niacin can reduce systolic, diastolic, and mean blood pressure in hypertensive patients. This effect is not observed in normotensive patients.

Likelihood Possible Evidence B
Bile Acid Sequestrants

Bile acid sequestrants can bind niacin and decrease absorption. Separate administration by 4-6 hours to avoid an interaction.
In vitro studies show that colestipol (Colestid) binds about 98% of available niacin and cholestyramine (Questran) binds 10% to 30%.

Likelihood Possible Evidence D
Gemfibrozil (Lopid)

Theoretically, concomitant use of niacin and gemfibrozil might increase the risk of myopathy in some patients.
A case of myopathy from concomitant use of niacin and gemfibrozil has been reported. Niacin alone has also been associated with cases of myopathy. Using gemfibrozil with niacin might further increase the risk of developing myopathy.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Theoretically, concomitant use of niacin and hepatotoxic drugs might increase the risk of hepatotoxicity.
Niacin has been associated with cases of liver toxicity, especially when used in pharmacologic doses. Sustained-release niacin preparations appear to be associated with a higher risk of hepatotoxicity than immediate-release niacin.

Likelihood Possible Evidence D
Hmg-Coa Reductase Inhibitors ("Statins")

Theoretically, concomitant use of niacin and statins might increase the risk of myopathy and rhabdomyolysis in some patients.
Some case reports have raised concerns that niacin might increase the risk of myopathy and rhabdomyolysis when combined with statins. However, a significantly increased risk of myopathy has not been demonstrated in clinical trials, including those using an FDA-approved combination of lovastatin and niacin (Advicor).

Likelihood Possible Evidence D
Probenecid (Benemid)

Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as probenecid.
Large doses of niacin reduce urinary excretion of uric acid, potentially causing hyperuricemia. Doses of uricosurics such as probenecid might need to be increased to maintain control of gout in patients who start taking niacin. People who have frequent attacks of gout despite uricosuric therapy should avoid niacin.

Likelihood Probable Evidence C
Sulfinpyrazone (Anturane)

Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as sulfinpyrazone.
Large doses of niacin reduce urinary excretion of uric acid, potentially causing hyperuricemia. Doses of uricosurics such as sulfinpyrazone might need to be increased to maintain control of gout in patients who start taking niacin. People who have frequent attacks of gout despite uricosuric therapy should avoid niacin.

Likelihood Probable Evidence C
Thyroid Hormone

Theoretically, niacin might antagonize the therapeutic effects of thyroid hormones.
Clinical research and case reports suggests that taking niacin can reduce serum levels of thyroxine-binding globulin by up to 25% and moderately reduce levels of thyroxine (T4). Patients taking thyroid hormone for hypothyroidism might need dose adjustments when using niacin.

Likelihood Probable Evidence D
Transdermal Nicotine (Nicoderm)

Theoretically, concomitant use of niacin and transdermal nicotine might increase the risk of flushing and dizziness.
Niacin and nicotine can both cause flushing and dizziness.

Likelihood Possible Evidence D
Warfarin (Coumadin)

There is limited evidence that niacin may increase the anticoagulant effects of warfarin.
In a case report, a patient on warfarin developed an elevated international normalized ratio (INR) of 3.9 after taking niacin for two weeks. The patient's INR was previously stable, ranging between 2 and 3 in recent months, and no other medication changes were identified. The elevated INR returned to therapeutic range within 4 days following the discontinuation of niacin.

Likelihood Possible Evidence D
Aspirin

Large doses of aspirin might alter the clearance of niacin.
Aspirin is often used with niacin to reduce niacin-induced flushing. Doses of 80-975 mg aspirin have been used, but 325 mg appears to be optimal. Aspirin also seems to reduce the clearance of niacin by competing for glycine conjugation. Taking aspirin 1 gram seems to reduce niacin clearance by 45%. This is probably a dose-related effect and not clinically significant with the more common aspirin dose of 325 mg.

Likelihood Likely Evidence B
Niacin full monograph & interactions

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
L-Theanine full monograph & interactions

L-5-Hydroxytryptophan3 drug types · 398 drugs

Carbidopa (Lodosyn)

Combining 5-HTP and carbidopa can increase the risk of serotonergic side effects.
Carbidopa is sometimes used with 5-HTP to minimize peripheral 5-HTP metabolism and boost the amount that reaches the brain. However, this combination might also increase the risk of some side effects including hypomania, restlessness, rapid speech, anxiety, insomnia, and aggressiveness. Combining carbidopa and 5-HTP might also increase the risk of scleroderma-like skin changes due to elevated serotonin levels.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, concomitant use of 5-HTP with medications that cause sedation might have additive effects.
In clinical trials, 5-HTP has been associated with drowsiness and somnolence.

Likelihood Possible Evidence D
Serotonergic Drugs

Combining serotonergic drugs with 5-HTP might cause additive serotonergic effects.
5-HTP can increase serotonin levels and cause serotonergic effects. Theoretically, combining serotonergic drugs with 5-HTP might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders. However, serotonin syndrome with 5-HTP has not yet been reported in humans. Monitor patients for signs of serotonin syndrome and other serotonergic side effects if using 5-HTP with serotonergic drugs.

Likelihood Possible Evidence D
L-5-Hydroxytryptophan full monograph & interactions

Vitamin B65 drug types · 210 drugs

Amiodarone (Cordarone)

Theoretically, vitamin B6 might increase the photosensitivity caused by amiodarone.
Despite initial case reports suggesting that pyridoxine may have a protective effect against amiodarone-induced photosensitivity, preliminary clinical research suggests that pyridoxine may actually exacerbate this adverse effect.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, vitamin B6 may have additive effects when used with antihypertensive drugs.
Research in hypertensive rats shows that vitamin B6 can decrease systolic blood pressure. Similarly, clinical research in patients with hypertension shows that taking high doses of vitamin B6 may reduce systolic and diastolic blood pressure, possibly by reducing plasma levels of epinephrine and norepinephrine.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

High doses of vitamin B6 may reduce the levels and clinical effects of phenobarbital.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenobarbital, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenobarbital to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Phenytoin (Dilantin)

High doses of vitamin B6 may reduce the levels and clinical effects of phenytoin.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenytoin, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenytoin to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Levodopa

Vitamin B6 may increase the metabolism of levodopa when taken alone, but not when taken in conjunction with carbidopa.
Vitamin B6 (pyridoxine) enhances the metabolism of levodopa, reducing its clinical effects. However, this interaction does not occur when carbidopa is used concurrently with levodopa (Sinemet). Therefore, it is not likely to be a problem in most people.

Likelihood Unlikely Evidence D
Vitamin B6 full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Neuro-5-HTP Plus, from the product label.

Biotics Research Corporation

See all Biotics Research Corporation products
Name
BIOTICS RESEARCH CORP.
City
Rosenberg
State
Texas
Phone Number
(281) 344-0909
Pharmacist Counseling Corner

Neuro-5-HTP Plus by Biotics Research Corporation: Common Questions

Does Neuro-5-HTP Plus by Biotics Research Corporation interact with any medications?
Yes. Based on its ingredients, Neuro-5-HTP Plus has a known interaction with 1,045 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Neuro-5-HTP Plus 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.
Can I take this while pregnant?
L-theanine and 5-HTP don't have enough safety data, so they're best avoided during pregnancy. Niacin at normal dietary and standard prenatal-vitamin levels is fine, but high-dose niacin should only be used if prescribed. Vitamin B6 at recommended levels is considered likely safe for pregnancy-related nausea under medical guidance. Talk to your doctor or pharmacist for personalized advice, especially if you're taking this for a specific reason.
Can I take this while breastfeeding?
L-theanine and 5-HTP lack sufficient safety data, so avoiding them while breastfeeding is advisable. Niacin and vitamin B6 at normal dietary and recommended supplement amounts are generally considered safe. Speak with your own doctor or pharmacist about your situation before starting.
What is 5-HTP and what does it do?
L-5-hydroxytryptophan (5-HTP) is a compound your body normally makes from the amino acid tryptophan. It's a precursor to serotonin, a brain chemical involved in mood and other functions. Research suggests it's possibly effective for depression, though side effects like nausea and drowsiness are common.
Does niacin in this product cause the 'niacin flush'?
Yes—up to 70% of people taking niacin experience flushing, a warm redness and tingling usually of the face and neck. It's more common at higher doses and is caused by blood vessel dilation. Flushing typically passes within a few minutes and often decreases with continued use.
What's L-theanine and will it make me drowsy?
L-theanine is an amino acid found naturally in tea. It's possibly effective for cognitive function and is thought to promote calm focus. Some people report drowsiness and increased sleep, so if you're sensitive to sedation, start with a lower dose and see how you respond.
Is this safe to take long-term?
L-theanine's long-term safety isn't well studied. Niacin at normal levels is safe but high supplemental doses over time can harm the liver and nerves. 5-HTP is generally well tolerated short-term; long-term data is limited. Vitamin B6 at high doses over time can cause nerve damage. If you're considering this long-term, check in with your own pharmacist or doctor to monitor your use.

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.

Neuro-5-HTP Plus label
Go deeper

The Full Monographs Behind Neuro-5-HTP Plus’s Ingredients

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

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

Niacin

Interacts with 727 drugs

Niacin (vitamin B3) is an essential nutrient your body needs for energy and metabolism, and deficiency is uncommon in most developed countries. Prescription-strength niacin has been used to...

Read the full Niacin monograph → Herb & supplement monograph

5-htp

Interacts with 398 drugs

5-HTP is a compound your body uses to make serotonin, and people take it as a supplement hoping to improve mood, sleep, and headaches. Some early research is promising, but the overall evide...

Read the full 5-htp monograph → Herb & supplement monograph

Vitamin B6

Interacts with 210 drugs

Vitamin B6 (pyridoxine) is an essential water-soluble vitamin that your body needs for metabolism, brain function, and making red blood cells. It is best known for helping with pregnancy-rel...

Read the full Vitamin B6 monograph →
Sources

Sources & How We Checked

Neuro-5-HTP Plus'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 136 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
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Vitamin B6 32 references
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