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Dietary supplement

Serotone 5-HTP 100 mg Ingredients & Drug Interactions

by Higher Nature

Serotone 5-HTP 100 mg 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 Serotone 5-HTP 100 mg 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

Serotone 5-HTP 100 mg is a dietary supplement by Higher Nature with 6 active ingredients. Its ingredients are commonly taken for preventing neural tube birth defects, treating or preventing folate deficiency, supporting pregnancy health.Based on those ingredients, 1,075 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Niacin, 5-HTP, Vitamin B6. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Serotone 5-HTP 100 mg by Higher Nature

Ask about any prescription or over-the-counter medication and we check it for interactions with Serotone 5-HTP 100 mg by Higher Nature — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Serotone 5-HTP 100 mg by Higher Nature

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 10, 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.

Serotone 5-HTP contains six active ingredients. The star ingredient is 5-HTP (5-hydroxytryptophan), a precursor to serotonin—a brain chemical linked to mood and sleep.

It's paired with folic acid, zinc, vitamin B6 (pyridoxine), biotin, and niacin (vitamin B3), all B vitamins that support nerve function and metabolism. The capsule also contains inactive ingredients: rice bran, silicon dioxide, and magnesium stearate as processing aids.

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: Mind health.
  • We looked for evidence on: Anxiety, Age-related cognitive decline, Alzheimer disease, Attention deficit-hyperactivity disorder (ADHD), Bipolar disorder, Cognitive function — and 4 related terms.
  • The strongest evidence on file: 5-htp is rated "Possibly Effective" for Depression (Natural Medicines).
  • Also on file: Folic Acid is rated "Possibly Effective" for Cognitive impairment, Depression.
  • Also on file: Vitamin B6 is rated "Possibly Ineffective" for Age-related cognitive decline, Alzheimer disease.

The evidence for this product's ingredients is mixed. Folic acid is effective for folate deficiency and likely effective for preventing birth-defect risks and reducing methotrexate side effects.

Zinc is effective for zinc deficiency and likely effective for Wilson disease, though only possibly effective for acne and diabetes. Vitamin B6 is effective for vitamin B6 deficiency and certain types of anemia, and possibly effective for morning sickness in pregnancy.

Biotin is likely effective only for biotin deficiency; the data we hold doesn't support it for hair loss or multiple sclerosis. Niacin is likely effective for pellagra and possibly effective for certain lipid disorders.

5-HTP is possibly effective for depression but shows insufficient evidence for ADHD, Alzheimer disease, or cerebellar ataxia. The product as a whole is positioned for mood support, but the evidence for 5-HTP specifically in depression is modest—talk with your doctor or pharmacist about whether it fits your needs.

The evidence, ingredient by ingredient Folic Acid Zinc Vitamin B6 Biotin Niacin 5-htp

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 6 of the 6 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 6 of 6.
  • General safety write-ups exist for 6 of 6.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Folic acid is generally well tolerated at standard doses, though doses of 5 mg daily or higher can cause abdominal cramps, diarrhea, and rash; very high doses may cause confusion, sleep trouble, or nausea. Zinc is well tolerated below 40 mg daily but can cause nausea, diarrhea, and a metallic taste; high long-term doses raise the risk of copper deficiency.

Vitamin B6 is safe at normal amounts but can cause nerve damage (sensory neuropathy) at very high doses or over long periods. Biotin is generally well tolerated even at high doses.

Niacin commonly causes flushing and gastrointestinal upset, especially at higher doses, and can harm the liver with sustained-release forms. 5-HTP is generally well tolerated short-term but often causes nausea, diarrhea, dizziness, drowsiness, or headache, and in rare cases can trigger aggression, hallucinations, or mania.

Pregnancy: folic acid is recommended at standard prenatal doses to prevent birth defects, but high late-pregnancy use has been linked to childhood asthma risk; 5-HTP has insufficient safety data and should be avoided. Breastfeeding: folic acid, zinc, and vitamin B6 are considered safe at normal levels; 5-HTP and biotin lack sufficient data—discuss with your doctor.

Side effects, ingredient by ingredient Folic Acid Zinc Vitamin B6 Biotin Niacin 5-htp

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?
  • 5 of the 6 matched ingredients can interact with medications — 5-htp, Niacin, Vitamin B6, Zinc, Folic Acid.
  • 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: 1,076 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 Serotone 5-HTP, double-check these medication types with your doctor or pharmacist: seizure medications (phenobarbital, phenytoin, primidone) — folic acid can reduce their levels or reverse their effects; cancer drugs (methotrexate, capecitabine, 5-fluorouracil) — folic acid may lower efficacy or raise toxicity; antibiotics (quinolones, tetracyclines, cephalexin) — zinc can reduce their levels; HIV medications (ritonavir, integrase inhibitors, biktarvy) — zinc may lower their effectiveness; blood pressure medications — both vitamin B6 and niacin may add to their effects; diabetes drugs — niacin can raise blood sugar and reduce their effects; blood thinners (anticoagulants) — niacin may increase bleeding risk; gout medications (allopurinol, probenecid) — niacin can interfere; cholesterol-lowering statins — niacin raises myopathy risk; psychiatric and neurological drugs that affect serotonin — 5-HTP can increase serotonergic effects; and carbidopa — 5-HTP combined with it raises side-effect risk. Also discuss any CNS depressants (sleep aids, sedatives) with your provider, as 5-HTP can add to drowsiness.

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 people seeking natural mood support, especially those interested in a B-vitamin complex combined with 5-HTP. If you take seizure medications, cancer treatments, antibiotics, HIV drugs, blood pressure or diabetes medications, or psychiatric drugs, you need to check your specific medications before starting—the ingredient interactions are substantial.

Anyone pregnant, breastfeeding, or on long-term high-dose supplements should discuss this with their doctor or pharmacist first.

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

Assessment coverage: 6 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Apr 22, 2021.

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 Serotone 5-HTP 100 mg, straight from the product label.

Brand Higher Nature
Barcode (UPC) 5031013100116
Net contents 30 Capsule(s)
Market status On market
Date entered into DSLD Apr 22, 2021
DSLD ID 245817
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Women (not pregnant or lactating), Gluten Free, Dairy Free
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 Serotone 5-HTP 100 mg by Higher Nature, 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
30
UPC/BARCODE
5031013100116
IngredientAmount% DV
Folic Acid100 mcg50%
Zinc5 mg50%
Vitamin B610 mg714%
Biotin50 mcg100%
Niacin30 mg NE188%
5-HTP100 mg--

Other ingredients: Rice Bran, L-5-Hydroxytryptophan, Capsule, Vitamin B3, Zinc Citrate, Vitamin B6, Vitamin B6, 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

NRV = Nutrient Reference Value

Mind Health

This product has not been tested on animals.

Formulation

Free from: Artificial colours, flavourings or preservatives, corn, dairy products, gluten, lactose, maize, salt, soya, sugar, wheat, yeast.

Vegetarian and vegan

Advanced formula Optimal benefit

Storage

Storage: Store in a cool, dry place out of reach of children.

Precautions

Storage: Store in a cool,dry place out of reach of children.

Do not exceed recommended daily intake. Food supplements should not be used as a substitute for a varied and balanced diet and healthy lifestyle.

Warning: Consult your doctor if under medical supervision or taking prescribed medications. Not advisable if pregnant, breastfeeding or if taking antidepressants.

Can cause drowsiness; do not drive or operate machinery if affected.

FDA Statement of Identity

Food Supplement

Formula

5-HTP is an amino acid needed to produce serotonin Vitamins B3 and B6 contribute to normal psychological function

Suggested/Recommended/Usage/Directions

Directions: Take 1 capsule a day preferably before bed with a carbohydrate snack. Do not exceed recommended daily intake. Food supplements should not be used as a substitute for a varied and balanced diet and healthy lifestyle.

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

See for yourself

Serotone 5-HTP 100 mg by Higher Nature label

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

Serotone 5-HTP 100 mg 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 Serotone 5-HTP 100 mg by Higher Nature

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 container30 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.

Folic Acid

Interacts with
40 drugs
100 mcg per serving

Folic acid is the man-made form of vitamin B9 and is one of the most well-studied supplements, especially for preventing serious birth defects when ta...

Folic Acid monograph & interactions

Zinc

Interacts with
67 drugs
5 mg per serving

Zinc is an essential mineral that your body needs for immune function, wound healing, taste, and smell. Most people get enough from food, but suppleme...

Zinc monograph & interactions

Vitamin B6

Interacts with
210 drugs
10 mg per serving

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

Biotin

No known
interactions
50 mcg per serving

Biotin (vitamin B7) is a water-soluble vitamin your body needs to turn food into energy and to support healthy hair, skin, and nails. Most people get...

Biotin monograph & interactions

Niacin

Interacts with
727 drugs
30 mg NE per serving Form: Vitamin B3

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

5-HTP

Interacts with
398 drugs
100 mg per serving Form: Griffonia simplicifolia Seed Extract

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...

5-HTP monograph & interactions

Other (inactive) ingredients: Rice Bran, L-5-Hydroxytryptophan, Capsule, Vitamin B3, Zinc Citrate, Vitamin B6, Vitamin B6, Silicon Dioxide, Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Serotone 5-HTP 100 mg by Higher Nature Drug Interactions

Want to check YOUR meds against Serotone 5-HTP 100 mg?

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
1,075Drugs
1,071 Moderate 4 Minor

Ingredients driving the most interactions

Niacin 727
5-HTP 398
Vitamin B6 210
Zinc 67
Folic Acid 40

Individual Drug Interactions

The ingredients in Serotone 5-HTP 100 mg interact with 1,075 drugs. Click any drug to see the details.

5 of the 6 ingredients in Serotone 5-HTP 100 mg interact with drugs. Each result below shows which ingredient is responsible. Niacin 5-HTP Vitamin B6 Zinc Folic Acid

Each ingredient & the kinds of drugs it affects

For each ingredient in Serotone 5-HTP 100 mg 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

5-HTP3 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
5-HTP 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

Zinc10 drug types · 67 drugs

Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Theoretically, zinc might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide should be taken at least 2 hours before or 6 hours after zinc containing products.

Likelihood Probable Evidence D
Cephalexin (Keflex)

Zinc might decrease cephalexin levels by chelating with cephalexin in the gut and preventing its absorption.
A pharmacokinetic study shows that zinc sulfate 250 mg taken concomitantly with cephalexin 500 mg decreases peak levels of cephalexin by 31% and reduces the exposure to cephalexin by 27%. Also, taking zinc sulfate 3 hours before cephalexin decreases peak levels of cephalexin by 11% and reduces the exposure to cephalexin by 18%. By decreasing cephalexin levels, zinc might increase the risk of treatment failure. This effect does not occur when zinc is taken 3 hours after the cephalexin dose. To avoid an interaction, advise patients take zinc sulfate 3 hours after taking cephalexin.

Likelihood Probable Evidence B
Cisplatin (Platinol-Aq)

Theoretically, zinc might interfere with the therapeutic effects of cisplatin.
Animal research suggests that zinc stimulates tumor cell production of the protein metallothionein, which binds and inactivates cisplatin. It is not known whether zinc supplements or high dietary zinc intake can cause clinically significant interference with cisplatin therapy. Cisplatin might also increase zinc excretion.

Likelihood Possible Evidence D
Integrase Inhibitors

Theoretically, taking zinc along with integrase inhibitors might decrease the levels and clinical effects of these drugs.
Zinc is a divalent cation. Pharmacokinetic studies have shown that other divalent cations such as calcium and iron can decrease blood levels of the integrase inhibitor dolutegravir through chelation.

Likelihood Possible Evidence D
Penicillamine (Cuprimine, Depen)

Zinc might reduce the levels and clinical effects of penicillamine.
By forming an insoluble complex with penicillamine, zinc interferes with penicillamine absorption and activity. Zinc supplements reduce the efficacy of low-dose penicillamine (0.5-1 gram/day), but do not seem to affect higher doses (1-2.75 gram/day), provided dosing times are separated. Advise patients to take zinc and penicillamine at least 2 hours apart.

Likelihood Probable Evidence B
Quinolone Antibiotics

Zinc can decrease the levels and clinical effects of quinolones antibiotics.
Quinolones form complexes with zinc in the gastrointestinal tract, reducing absorption of both the quinolone and zinc if taken at the same time. Advise patients to take these drugs at least 2 hours before, or 4-6 hours after, zinc supplements.

Likelihood Probable Evidence B
Ritonavir (Norvir)

Zinc modestly reduces levels of ritonavir.
Clinical research shows that zinc might reduce serum ritonavir levels by chelating with ritonavir in the gut and preventing its absorption. In patients with HIV, ritonavir is taken with atazanavir to prevent the metabolism and increase the effects of atazanavir. A pharmacokinetic study shows that, in patients being treated with atazanavir/ritonavir, co-administration of zinc sulfate (Solvazinc tablets) 125 mg as a single dose or as multiple daily doses for 2 weeks reduces plasma levels of ritonavir by about 16%. However, atazanavir levels still remains high enough to prevent HIV virus replication. Therefore, the decrease in ritonavir levels is not likely to be clinically significant.

Likelihood Probable Evidence B
Tetracycline Antibiotics

Zinc might reduce levels of tetracycline antibiotics.
Tetracyclines form complexes with zinc in the gastrointestinal tract, which can reduce absorption of both the tetracycline and zinc when taken at the same time. Taking zinc sulfate 200 mg with tetracycline reduces absorption of the antibiotic by 30% to 40%. Demeclocycline and minocycline cause a similar interaction. However, doxycycline does not seem to interact significantly with zinc. Advise patients to take tetracyclines at least 2 hours before, or 4-6 hours after, zinc supplements to avoid any interactions.

Likelihood Probable Evidence B
Amiloride (Midamor)

Amiloride can modestly reduce zinc excretion and increase zinc levels.
Clinical research shows that amiloride can reduce urinary zinc excretion, especially at doses of 10 mg per day or more. This zinc-sparing effect can help to counteract zinc losses caused by thiazide diuretics, but it is unlikely to cause zinc toxicity at usual amiloride doses. The other potassium-sparing diuretics, spironolactone (Aldactone) and triamterene (Dyrenium), do not seem to have a zinc-sparing effect.

Likelihood Probable Evidence B
Atazanavir (Reyataz)

Zinc modestly reduces levels of atazanavir, although this effect does not seem to be clinically significant.
Clinical research shows that zinc might decrease serum atazanavir levels by chelating with atazanavir in the gut and preventing its absorption. Although a single dose of zinc sulfate (Solvazinc tablets) 125 mg orally does not affect atazanavir concentrations in patients being treated with atazanavir/ritonavir, co-administration of zinc sulfate 125 mg daily for 2 weeks reduces plasma levels of atazanavir by about 22% in these patients. However, despite this decrease, atazanavir levels still remain at high enough concentrations for the prevention of HIV virus replication.

Likelihood Probable Evidence B
Zinc full monograph & interactions

Folic Acid7 drug types · 40 drugs

5-Fluorouracil

Theoretically, high doses of folic acid might increase the toxicity of 5-fluorouracil.
Increases in gastrointestinal side effects of 5-fluorouracil, such as stomatitis and diarrhea, have been described in two clinical studies when leucovorin, a form of folic acid, was administered with 5-fluorouracil.

Likelihood Possible Evidence D
Capecitabine (Xeloda)

Use of high-dose folic acid might contribute to capecitabine toxicity.
Clinical research suggests that higher serum folate levels are associated with an increased risk for moderate or severe toxicity during capecitabine-based treatment for colorectal cancer. Additionally, in one case report, taking folic acid 15 mg daily might have contributed to increased toxicity, including severe diarrhea, vomiting, edema, hand-foot syndrome, and eventually death, in a patient prescribed capecitabine.

Likelihood Possible Evidence D
Methotrexate (Trexall, Others)

Folic acid might reduce the efficacy of methotrexate as a cancer treatment when given concurrently.
Methotrexate exerts its cytotoxic effects by preventing conversion of folic acid to the active form needed by cells. There is some evidence that folic acid supplements reduce the efficacy of methotrexate in the treatment of acute lymphoblastic leukemia, and theoretically they could reduce its efficacy in the treatment of other cancers. Advise cancer patients to consult their oncologist before using folic acid supplements. In patients treated with long-term, low-dose methotrexate for rheumatoid arthritis (RA) or psoriasis, folic acid supplements can reduce the incidence of side effects, without reducing efficacy.

Likelihood Probable Evidence B
Phenobarbital (Luminal)

Folic acid might have antagonistic effects on phenobarbital and increase the risk for seizures.
Folic acid can have direct convulsant activity in some people, reversing the effects of phenobarbital and worsening seizure control. Monitor closely for increased seizure activity.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Folic acid might reduce serum levels of phenytoin in some patients.
Folic acid may be a cofactor in phenytoin metabolism. Folic acid, in doses of 1 mg daily or more, can reduce serum levels of phenytoin in some patients. Increases in seizure frequency have been reported. If folic acid supplements are added to established phenytoin therapy, monitor serum phenytoin levels closely. If phenytoin and folic acid are started at the same time and continued together, adverse changes in phenytoin pharmacokinetics are avoided. Note that phenytoin also reduces serum folate levels.

Likelihood Probable Evidence B
Primidone (Mysoline)

Folic acid might have antagonistic effects on primidone and increase the risk for seizures.
Folic acid can have direct convulsant activity in some people, reversing the effects of primidone and worsening seizure control. Monitor closely for increased seizure activity. Note that primidone also reduces serum folate levels.

Likelihood Probable Evidence B
Pyrimethamine (Daraprim)

Folic acid might antagonize the effects of pyrimethamine.
Folic acid can antagonize the antiparasitic effects of pyrimethamine against toxoplasmosis and Pneumocystis carinii pneumonia. Folic acid doesn't antagonize the effects of pyrimethamine in the treatment of malaria, because malarial parasites cannot use exogenous folic acid. Use folinic acid as an alternative to folic acid when indicated.

Likelihood Probable Evidence D
Folic Acid full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Serotone 5-HTP 100 mg, from the product label.

Higher Nature

See all Higher Nature products
Name
Higher Nature Ltd
Street Address
10 Discovery Way
City
Horam, East Sussex
ZipCode
TN21 0GE
Web Address
highernature.com
Pharmacist Counseling Corner

Serotone 5-HTP 100 mg by Higher Nature: Common Questions

Does Serotone 5-HTP 100 mg by Higher Nature interact with any medications?
Yes. Based on its ingredients, Serotone 5-HTP 100 mg has a known interaction with 1,075 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Serotone 5-HTP 100 mg 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 if I'm pregnant?
Folic acid in this product is recommended at standard prenatal doses to help prevent birth defects. However, 5-HTP has not been studied enough in pregnancy and should be avoided. Because this is a multi-ingredient product, talk with your doctor or pharmacist about whether it's right for you during pregnancy—they can advise on the folic acid benefit versus the 5-HTP risk.
What is 5-HTP and what does it do?
5-HTP is a natural amino acid your body makes from the amino acid tryptophan. It's a building block for serotonin, a brain chemical involved in mood, sleep, and appetite. The evidence shows it's possibly effective for depression, but the data isn't strong enough to call it a proven treatment.
Will this make me drowsy?
Yes, drowsiness and dizziness are common side effects of 5-HTP. Additionally, if you take any sedating medications or sleep aids, this product could add to that effect. Start with a low dose to see how you react, and let your doctor know if drowsiness is a problem.
What stomach side effects might I get?
Nausea, diarrhea, abdominal pain, and loss of appetite are the most common digestive complaints, particularly when starting 5-HTP or taking higher doses. These often ease with continued use, and taking it with food or spreading out the dose may help. If they don't improve, talk to your pharmacist.
Is this safe if I'm on multiple medications?
Because folic acid, zinc, vitamin B6, and niacin each interact with certain drugs—and 5-HTP interacts with serotonergic medications—this product isn't safe for everyone. Use the medication checker on this page to look up your exact drugs, and have a conversation with your doctor or pharmacist before starting.
Why does this product have so many vitamins if it's for mood?
B vitamins support nerve function and the production of neurotransmitters like serotonin. Folic acid, B6, and niacin all play roles in mood and brain health. Together with 5-HTP, they're meant to work synergistically, though the evidence for the product as a whole is limited.

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.

Serotone 5-HTP 100 mg label
Go deeper

The Full Monographs Behind Serotone 5-HTP 100 mg’s Ingredients

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

Herb & supplement monograph

Folic Acid

Interacts with 40 drugs

Folic acid is the man-made form of vitamin B9 and is one of the most well-studied supplements, especially for preventing serious birth defects when taken before and during early pregnancy. I...

Read the full Folic Acid monograph → Herb & supplement monograph

Zinc

Interacts with 67 drugs

Zinc is an essential mineral that your body needs for immune function, wound healing, taste, and smell. Most people get enough from food, but supplements can help correct or prevent a defici...

Read the full Zinc 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 → Herb & supplement monograph

Biotin

Biotin (vitamin B7) is a water-soluble vitamin your body needs to turn food into energy and to support healthy hair, skin, and nails. Most people get plenty from a normal diet, and true defi...

Read the full Biotin 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 →
Sources

Sources & How We Checked

Serotone 5-HTP 100 mg'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 278 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.

Folic Acid 56 references
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  41. Crider KS, Cordero AM, Qi YP, Mulinare J, Dowling NF, Berry RJ. Prenatal folic acid and risk of asthma in children: a systematic review and meta-analysis. Am J Clin Nutr. 2013;98(5):1272-81. PubMed
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  44. Tio M, Andrici J, Cox MR, Eslick GD. Folate intake and the risk of prostate cancer: a systematic review and meta-analysis. Prostate Cancer Prostatic Dis. 2014;17(3):213-9. PubMed
  45. Tomaszewski JJ, Richman EL, Sadetsky N, O'Keefe DS, Carroll PR, Davies BJ, Chan JM. Impact of folate intake on prostate cancer recurrence following definitive therapy: data from CaPSURE. J Urol. 2014;191(4):971-6. PubMed
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  48. Vila-Nova C, Wehby GL, Queirós FC, Chakraborty H, Félix TM, Goco N, Moore J, Gewehr EV, Lins L, Affonso CM, Murray JC. Periconceptional use of folic acid and risk of miscarriage - findings of the Oral Cleft Prevention Program in Brazil. J Perinat Med. 201 PubMed
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See these in context on the Folic Acid monograph →

Zinc 88 references
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