Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

5-HTP Ingredients & Drug Interactions

by Nature's Way

5-HTP label
See full label image
Tablet Or Pill 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 5-HTP 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

5-HTP is a dietary supplement by Nature's Way with 3 active ingredients. Its ingredients are commonly taken for morning sickness in pregnancy, premenstrual syndrome (pms), preventing or treating b6 deficiency.Based on those ingredients, 716 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are L-5-Hydroxytryptophan, Vitamin B6, Vitamin C. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against 5-HTP by Nature's Way

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

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HelloPharmacist Scorecard of 5-HTP by Nature's Way

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 Jul 11, 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 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains three active ingredients: vitamin B6, vitamin C, and L-5-hydroxytryptophan (5-HTP). Vitamin B6 supports red blood cell formation and nervous system function.

Vitamin C is an antioxidant that supports immune function and collagen production. 5-HTP is an amino acid precursor to serotonin, a neurotransmitter involved in mood and sleep regulation.

The remaining ingredients are inactive excipients—cellulose, maltodextrin, sodium croscarmellose, stearic acid, silica, ethylcellulose, sodium alginate, medium chain triglyceride, and oleic acid—that serve as binders, fillers, and flow agents to form the tablet.

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: help make serotonin support positive mood.
  • We looked for evidence on: Anxiety, Depression, Mood support, Emotional well-being.
  • 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.
  • Also on file: Vitamin B6 is rated "Insufficient Reliable Evidence To Rate" for Anxiety, Depression, Postpartum depression.

Vitamin B6 is effective for sideroblastic anemia and vitamin B6 deficiency, and is likely effective for high homocysteine levels; it's possibly effective for pregnancy-related nausea and vomiting. Vitamin C is effective for vitamin C deficiency and possibly effective for anemia of chronic disease, atrial fibrillation, cataracts, and exercise-related infections.

5-HTP is possibly effective for depression, but is possibly ineffective for Down syndrome, and there isn't enough evidence to rate it for Alzheimer's disease, panic disorder, or cerebellar ataxia.

The evidence, ingredient by ingredient Vitamin B6 Vitamin C 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 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Vitamin B6 is well tolerated at doses under 100 mg daily, but high doses over time can damage nerves (sensory neuropathy); the risk increases sharply at doses above 1,000 mg daily or cumulative totals of 1,000 grams or more, though neuropathy can occur at lower doses. Common side effects include abdominal pain, headache, heartburn, nausea, and vomiting.

Vitamin C is generally safe at normal dietary and supplement doses but can cause abdominal cramps, heartburn, nausea, vomiting, and diarrhea at high doses above 2 grams daily; it may increase kidney stone risk in susceptible people. 5-HTP is generally well tolerated short-term but commonly causes nausea, vomiting, abdominal pain, diarrhea, dizziness, drowsiness, fatigue, headache, and insomnia in a dose-dependent manner.

Rare serious effects include aggression, hallucinations, and mania. For pregnancy: vitamin C data suggests likely safety at normal amounts and possible unsafety at high doses; there isn't enough safety information on 5-HTP during pregnancy or breastfeeding — talk with your doctor or pharmacist before use.

Side effects, ingredient by ingredient Vitamin B6 Vitamin C 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?
  • 3 of the 3 matched ingredients can interact with medications — 5-htp, Vitamin B6, Vitamin C.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; cancer treatments; Parkinson's medications.
  • For scale: 716 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 this product, double-check with your pharmacist if you take: blood pressure medications (vitamin B6), blood thinners like warfarin (vitamin C), birth control or hormone therapy (vitamin C), chemotherapy drugs (vitamin C), seizure medications like phenytoin or phenobarbital (vitamin B6), antidepressants or serotonergic drugs (5-HTP), sedating medications (5-HTP), Parkinson's medications including levodopa or carbidopa (vitamin B6 and 5-HTP), thyroid medication (vitamin C), or amiodarone for heart rhythm (vitamin B6).

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 three-ingredient product may help with depression or support general health, but it interacts with a wide range of medications including blood pressure drugs, blood thinners, birth control, chemotherapy agents, thyroid medication, and serotonergic antidepressants. If you take any prescription or over-the-counter medication, check it against this product's interactions before starting.

If you're pregnant, breastfeeding, or taking seizure or Parkinson's medications, talk with your pharmacist first.

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

Assessment coverage: 3 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Feb 23, 2025.

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 5-HTP, straight from the product label.

Brand Nature's Way
Barcode (UPC) 033674452400
Net contents 30 Tablet(s)
Market status On market
Date entered into DSLD Feb 23, 2025
DSLD ID 327852
Product type Other Combinations
Supplement form Tablet Or Pill
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Children 4 or More Years of Age, Vegan, Vegetarian, Adult (18 - 50 Years), Women (not pregnant or lactating), Gluten 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 5-HTP by Nature's Way, 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 Tablet(s)
Maximum serving Sizes:
2 Tablet(s)
Servings per container
15
UPC/BARCODE
033674452400
IngredientAmount% DV
Total Carbohydrates1 Gram(s)1%
Vitamin B68 mg471%
Vitamin C120 mg133%
L-5-Hydroxytryptophan100 mg--

Other ingredients: Cellulose, Maltodextrin, Sodium Croscarmellose, Stearic Acid, Silica, Ethylcellulose, Sodium Alginate, Medium Chain Triglyceride, Oleic Acid

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.
Formulation

Helps make serotonin to support a positive mood

Vegan Gelatin Free

Vegan Gelatin Free

Enteric coated

Gluten free. No wheat, soy, dairy, gelatin, or artificial colors.

Bottled and tested in the USA

Formula

5-HTP provides neurotransmitter-production support

L-5-Hydroxytryptophan Vitamins B6 & C 5-HTP from Griffonia seed extract 50 mg per tablet

Precautions

Warning: Do not take this product if you are under 12 years of age, or if you are pregnant or nursing.

Warning: Do not take this product if you are under 12 years of age, or if you are pregnant or nursing. Do not take this product if you have or are taking medication for epilepsy, scleroderma, or Parkinson's disease, or if you are taking anti-depressants. If you are taking any medications, consult a healthcare professional before use.

If you suffer from gastrointestinal (GI) disorders such as ulcers, irritable bowel syndrome, Crohn's disease, ulcerative colitis, or celiac disease, you should not use 5-HTP. Some individuals may experience gastrointestinal (GI) upset including abdominal cramping, nausea, or diarrhea while taking this product. If discomfort persists, discontinue use. This product may cause drowsiness; do not drive or operate heavy machinery while taking this product.

Keep out of reach of children.

Safety sealed with inner seal. Do not use if seal is broken or missing.

Seals/Symbols

Vegan Gelatin Free

General Statements

Bottle made from 50% post-consumer recycled plastic

FDA Disclaimer Statement

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

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Recommendation: Adults take 1-2 tablets three times daily with meals, or as recommended by a healthcare professional.

Storage

Keep tightly closed. Store at room temperature. Avoid excessive heat and direct sunlight.

Brand IP Statement(s)

Copyright 2024 Nature's Way Brands, LLC

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

See for yourself

5-HTP by Nature's Way label

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

5-HTP 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 5-HTP by Nature's Way

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Tablet(s) Dosage formTablet Or Pill Servings per container15 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.

Vitamin B6

Interacts with
210 drugs
8 mg per serving Form: Pyridoxine Hydrochloride

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

Vitamin C

Interacts with
207 drugs
120 mg per serving Form: Ascorbic Acid

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...

Vitamin C monograph & interactions

L-5-Hydroxytryptophan

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...

L-5-Hydroxytryptophan monograph & interactions

Other (inactive) ingredients: Cellulose, Maltodextrin, Sodium Croscarmellose, Stearic Acid, Silica, Ethylcellulose, Sodium Alginate, Medium Chain Triglyceride, Oleic Acid. These complete the product’s ingredient list but are not active constituents.

Interaction report

5-HTP by Nature's Way Drug Interactions

Want to check YOUR meds against 5-HTP?

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
716Drugs
670 Moderate 46 Minor

Ingredients driving the most interactions

L-5-Hydroxytryptophan 398
Vitamin B6 210
Vitamin C 207

Individual Drug Interactions

The ingredients in 5-HTP interact with 716 drugs. Click any drug to see the details.

3 of the 3 ingredients in 5-HTP interact with drugs. Each result below shows which ingredient is responsible. L-5-Hydroxytryptophan Vitamin B6 Vitamin C

Each ingredient & the kinds of drugs it affects

For each ingredient in 5-HTP 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.

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

Vitamin C13 drug types · 207 drugs

Alkylating Agents

Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Aluminum

Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption. In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely. Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.

Likelihood Probable Evidence B
Antitumor Antibiotics

Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Estrogens

Vitamin C might increase blood levels of estrogens.
Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products. It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall. When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements. Monitor these patients for estrogen-related side effects.

Likelihood Probable Evidence B
Fluphenazine (Prolixin)

Theoretically, vitamin C might decrease levels of fluphenazine.
In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started. The mechanism is not known, and there is no further data to confirm this interaction.

Likelihood Possible Evidence D
Indinavir (Crixivan)

Vitamin C can modestly reduce indinavir levels.
One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Vitamin C can increase levothyroxine absorption.
Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH.

Likelihood Probable Evidence B
Warfarin (Coumadin)

High-dose vitamin C might reduce the levels and effectiveness of warfarin.
Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption. There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time. Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant. However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

High-dose vitamin C might slightly prolong the clearance of acetaminophen.
A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases. This effect is not likely to be clinically significant.

Likelihood Probable Evidence B
Aspirin

Acidification of the urine by vitamin C might increase aspirin levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction is not clinically significant.

Likelihood Possible Evidence B
Choline Magnesium Trisalicylate (Trilisate)

Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Niacin

Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% in patients with coronary disease. It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.

Likelihood Possible Evidence A
Salsalate (Disalcid)

Acidification of the urine by vitamin C might increase salsalate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Vitamin C full monograph & interactions
The maker

Brand information

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

Nature's Way

See all Nature's Way products
Name
Nature's Way Brands, LLC
City
Green Bay
State
WI
ZipCode
54311
Phone Number
1-800-962-8873
Web Address
naturesway.com
Pharmacist Counseling Corner

5-HTP by Nature's Way: Common Questions

Does 5-HTP by Nature's Way interact with any medications?
Yes. Based on its ingredients, 5-HTP has a known interaction with 716 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
5-HTP contains 3 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 on birth control?
The vitamin C in this product may increase blood levels of estrogen from birth control or hormone therapy, which could affect how well it works or increase side effects. Talk with your pharmacist or doctor before starting to see if it's right for you.
Does 5-HTP really help with depression?
The evidence shows 5-HTP is possibly effective for depression, but the proof isn't as strong as for many prescription antidepressants. If you're considering it instead of or alongside medication, talk with your doctor.
What are the most common side effects?
The most common side effects are nausea, vomiting, abdominal pain, diarrhea, headache, drowsiness, and fatigue — most of these are dose-dependent and may improve with time. If they're bothersome, tell your pharmacist.
Is it safe to take high doses of the vitamins in this product?
No. High doses of vitamin B6 can damage nerves over time; vitamin C at high doses can cause diarrhea and kidney stones in susceptible people. Stick to the recommended dose and don't exceed it without guidance from your healthcare provider.
Can I take this while pregnant?
Vitamin C at normal doses is likely safe in pregnancy; 5-HTP doesn't have enough safety data — the facts we hold advise against it. Talk with your obstetrician or pharmacist before using this product during pregnancy.
Can I take this while breastfeeding?
We don't have enough safety data on 5-HTP during breastfeeding to say yes or no. Talk with your doctor or pharmacist about whether this product is right for you while nursing.

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.

5-HTP label
Go deeper

The Full Monographs Behind 5-HTP’s Ingredients

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

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

Vitamin C

Interacts with 207 drugs

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for immune function, collagen, and acts as an...

Read the full Vitamin C 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

5-HTP'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 115 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.

Vitamin B6 32 references
  1. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  2. Yates AA, Schlicker SA, Suitor CW. Dietary reference intakes: The new basis for recommendations for calcium and related nutrients, B vitamins, and choline. J Am Diet Assoc 1998;98:699-706. PubMed
  3. Geerling BJ, Dagnelie PC, Badart-Smook A, et al. Diet as a risk factor for the development of ulcerative colitis. Am J Gastroenterol 2000;95:1008-13. PubMed
  4. South M. Neonatal seizures after pyridoxine use -- reply. Lancet 1999;354:2083. PubMed
  5. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (2000). Washington, DC: National Academy Press, 2000. Available at: http://b
  6. Baxter P, Aicardi J. Neonatal seizures after pyridoxine use. Lancet 1999;354:2082-3. PubMed
  7. Bendich A, Cohen M. Vitamin B6 safety issues. Ann N Y Acad Sci 1990;585:321-30.
  8. Schaumburg H, Kaplan J, Windebank A. Sensory neuropathy from pyridoxine abuse. A new megavitamin syndrome. N Engl J Med 1983;309:445-8. PubMed
  9. Gordon N. Pyridoxine dependency: an update. Dev Med Child Neurol 1997;39:63-5. PubMed
  10. Lewis PJ. Pain in the hand and wrist. Pyridoxine supplements may help patients with carpal tunnel syndrome. BMJ 1995;310:1534. PubMed
  11. Kaufman G. Pyridoxine against amiodarone-induced photosensitivity (letter). Lancet 1984;1:51-2. PubMed
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Vitamin C 51 references
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5-htp 32 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.

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