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Dietary supplement

Enteric Coated 5-HTP Extra Strength 100 mg Ingredients & Drug Interactions

by Swanson Ultra

Enteric Coated 5-HTP Extra Strength 100 mg label
See full label image
Tablet Or Pill Category: Amino Acid/protein
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 Enteric Coated 5-HTP Extra Strength 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

Enteric Coated 5-HTP Extra Strength 100 mg is a dietary supplement by Swanson Ultra with 1 active ingredient. Its ingredients are commonly taken for low mood or depression, anxiety and stress, sleep problems.Based on those ingredients, 398 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are L-5-Hydroxytryptophan. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Enteric Coated 5-HTP Extra Strength 100 mg by Swanson Ultra

Ask about any prescription or over-the-counter medication and we check it for interactions with Enteric Coated 5-HTP Extra Strength 100 mg by Swanson Ultra — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Enteric Coated 5-HTP Extra Strength 100 mg by Swanson Ultra

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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: L-5-hydroxytryptophan (5-HTP), an amino acid your body naturally makes and uses to produce serotonin, a chemical messenger tied to mood, sleep, and pain regulation. The tablet also includes inactive ingredients like dicalcium phosphate, cellulose, and magnesium stearate for structure and binding, plus an enteric coating that helps the tablet dissolve in your small intestine rather than your stomach.

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

This product doesn't appear to be marketed for a specific use, so we graded 5-htp's overall clinical evidence instead.

Moderate

Some clinical evidence supports 5-htp for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredient's overall clinical evidence instead.
  • On file: Depression — rated "Possibly Effective" (Natural Medicines).

The evidence for 5-HTP in depression is listed as possibly effective — meaning some studies show benefit, but more research is needed to be certain. For other conditions in our data, including Alzheimer's disease and panic disorder, there isn't enough reliable evidence to rate it one way or the other.

Down syndrome showed possibly ineffective in the studies we hold.

The evidence, ingredient by ingredient 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 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Orally, 5-HTP is generally well tolerated in the short term. The most common side effects are stomach upset (nausea, vomiting, abdominal pain, diarrhea, constipation), dizziness, drowsiness, headache, and loss of appetite — and these often depend on how much you take and how quickly you increase the dose.

Some people report these ease over time with continued use. Rare serious side effects include aggression, hallucinations, and mania, especially at high doses or when combined with carbidopa.

During pregnancy, there isn't enough safety information, so the data advises against use. The same holds for breastfeeding — talk with your doctor or pharmacist about whether this is right for you in either situation.

Side effects, ingredient by ingredient 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?
  • 1 of the 1 matched ingredient can interact with medications — 5-htp.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: Parkinson's medications.
  • For scale: 398 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, check with your pharmacist if you use serotonergic drugs (most antidepressants, some migraine and pain medications), CNS depressants (sleep aids, anxiety medications, narcotic pain relievers), or carbidopa for Parkinson's. All three categories have documented Moderate interactions with 5-HTP.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence behind its ingredients' uses. Moderate medication interactions have been identified, and safety information is well characterized.

5-HTP may help some people with depression, but it affects serotonin and requires caution, especially if you take antidepressants or other serotonin-related medications. If you're on any prescription drugs, check them with a pharmacist before starting — this ingredient interacts with a broad range of medications.

Stomach upset is common, and mood changes are rare but possible.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Apr 25, 2019.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Enteric Coated 5-HTP Extra Strength 100 mg, straight from the product label.

Brand Swanson Ultra
Barcode (UPC) 087614026671
Net contents 30 Tablet(s)
Market status On market
Date entered into DSLD Apr 25, 2019
DSLD ID 184994
Product type Amino Acid/protein
Supplement form Tablet Or Pill
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 Enteric Coated 5-HTP Extra Strength 100 mg by Swanson Ultra, 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:
1 Tablet(s)
UPC/BARCODE
087614026671
IngredientAmount% DV
L-5-Hydroxytryptophan100 mg--

Other ingredients: Dicalcium Phosphate, Cellulose, Stearic Acid, Croscarmellose Sodium, Magnesium Stearate, Silica, Enteric Coating

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

The Most Advanced Nutrition Technology Tablets

To reorder, call toll free 1-800-437-4148 or visit our website at www.swansonvitamins.com

FDA Statement of Identity

Dietary Supplement

Seals/Symbols

Guaranteed purity & potency

Precautions

Do not use if seal is broken.

Keep out of reach of children.

Warning: Do not take this product if you are taking a prescription antidepressant or if you are pregnant or nursing. Consult your healthcare provider before use if you have a medical condition or if you are taking any prescription medications.

Storage

Store in a cool, dry place.

Suggested/Recommended/Usage/Directions

Suggested use: As a dietary supplement, take one tablet per day with water.

General

SWU667 Rev 0 08 02 17

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

See for yourself

Enteric Coated 5-HTP Extra Strength 100 mg by Swanson Ultra label

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

Enteric Coated 5-HTP Extra Strength 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 Enteric Coated 5-HTP Extra Strength 100 mg by Swanson Ultra

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Tablet(s) Dosage formTablet Or Pill Amounts shown are per serving.

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: Dicalcium Phosphate, Cellulose, Stearic Acid, Croscarmellose Sodium, Magnesium Stearate, Silica, Enteric Coating. These complete the product’s ingredient list but are not active constituents.

Interaction report

Enteric Coated 5-HTP Extra Strength 100 mg by Swanson Ultra Drug Interactions

Want to check YOUR meds against Enteric Coated 5-HTP Extra Strength 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
398Drugs
398 Moderate

Ingredients driving the most interactions

L-5-Hydroxytryptophan 398

Individual Drug Interactions

The ingredients in Enteric Coated 5-HTP Extra Strength 100 mg interact with 398 drugs. Click any drug to see the details.

1 of the 1 ingredient in Enteric Coated 5-HTP Extra Strength 100 mg interact with drugs. Each result below shows which ingredient is responsible. L-5-Hydroxytryptophan

Each ingredient & the kinds of drugs it affects

For each ingredient in Enteric Coated 5-HTP Extra Strength 100 mg with known interactions, here are the types of medications it 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
The maker

Brand information

Manufacturer and brand details for Enteric Coated 5-HTP Extra Strength 100 mg, from the product label.

Swanson Ultra

See all Swanson Ultra products
Name
Swanson Health Products
City
Fargo
State
ND
ZipCode
58104
Phone Number
1-800-437-4148
Web Address
www.swansonvitamins.com
Pharmacist Counseling Corner

Enteric Coated 5-HTP Extra Strength 100 mg by Swanson Ultra: Common Questions

Does Enteric Coated 5-HTP Extra Strength 100 mg by Swanson Ultra interact with any medications?
Yes. Based on its ingredients, Enteric Coated 5-HTP Extra Strength 100 mg has a known interaction with 398 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Enteric Coated 5-HTP Extra Strength 100 mg contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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.
Will this help my depression?
The evidence shows 5-HTP is possibly effective for depression, meaning some people see benefit, but more research is needed. Whether it'll work for you is individual — talk with your doctor about whether it's a fit for your situation.
What are the most common side effects?
Stomach complaints are most frequent — nausea, vomiting, abdominal pain, diarrhea, and loss of appetite. Drowsiness, dizziness, headache, and insomnia also occur. Most are dose-dependent, and some people find they improve with continued use.
Is it safe to take during pregnancy?
There isn't enough safety information available. The data advises against use during pregnancy. Talk with your doctor or midwife for personalized advice.
Can I take it while breastfeeding?
There isn't enough safety data, so it's advised against. Your pharmacist or doctor can discuss whether it's okay for your specific situation.
Why does this have an enteric coating?
The enteric coating delays release of 5-HTP until it reaches your small intestine rather than your stomach. This can help reduce stomach upset that might otherwise occur.
What dose is in each tablet?
Each tablet contains 100 mg of L-5-hydroxytryptophan. It's labeled 'Extra Strength,' so follow the package directions or ask your pharmacist what amount is right for you.

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

Not sure if Enteric Coated 5-HTP Extra Strength 100 mg is safe with your meds?

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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.

Enteric Coated 5-HTP Extra Strength 100 mg label
Go deeper

The Full Monographs Behind Enteric Coated 5-HTP Extra Strength 100 mg’s Ingredients

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

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

Enteric Coated 5-HTP Extra Strength 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 32 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.

5-htp 32 references
  1. Birdsall TC. 5-Hydroxytryptophan: A Clinically-Effective Serotonin Precursor. Altern Med Rev 1998;3:271-80.
  2. Michelson D, Page SW, Casey R, et al. An eosinophilia-myalgia syndrome related disorder associated with exposure to L-5-hydroxytryptophan. J Rheumatol 1994;21:2261-5.
  3. Cangiano C, Ceci F, Cancino A, et al. Eating behavior and adherence to dietary prescriptions in obese adult subjects treated with 5-hydroxytryptophan. Am J Clin Nutr 1992;56:863-7. PubMed
  4. U.S. Food and Drug Administration. Impurities confirmed in dietary supplement 5-hydroxy-L-tryptophan. FDA Talk Paper, August 31, 1998; T98-48.
  5. Sternberg EM, Van Woert MH, Young SN, et al. Development of a scleroderma-like illness during therapy with L-5-hydroxytryptophan and carbidopa. N Engl J Med 1980;303:782-7. PubMed
  6. Poldinger W, Calanchini B, Schwarz W. A functional-dimensional approach to depression: serotonin deficiency as a target syndrome in a comparison of 5-hydroxytryptophan and fluvoxamine. Psychopathology 1991;24:53-81.
  7. Ribeiro CA. L-5-Hydroxytryptophan in the prophylaxis of chronic tension-type headache: a double-blind, randomized, placebo-controlled study. Headache 2000;40:451-6.
  8. U. S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, Office of Nutritional Products, Labeling, and Dietary Supplements. Information Paper on L-Tryptophan and 5-hydroxy-L-tryptophan, February 2001.
  9. Singhal AB, Caviness VS, Begleiter AF, et al. Cerebral vasoconstriction and stroke after use of serotonergic drugs. Neurology 2002;58:130-3. PubMed
  10. Johnson KL, Klarskov K, Benson LM, et al. Presence of peak X and related compounds: the reported contaminant in case related 5-hydroxy-L-tryptophan associated with eosinophilia-myalgia syndrome. J Rheumatol 1999;26:2714-7.
  11. Takahashi S, Kondo H, Kato N. Effect of l-5-hydroxytryptophan on brain monoamine metabolism and evaluation of its clinical effect in depressed patients. J Psychiatr Res 1975;12:177-87. PubMed
  12. Iovieno, N., Dalton, E. D., Fava, M., and Mischoulon, D. Second-tier natural antidepressants: review and critique. J Affect.Disord. 2011;130(3):343-357. PubMed
  13. den Boer JA, Westenberg HG. Behavioral, neuroendocrine, and biochemical effects of 5-hydroxytryptophan administration in panic disorder. Psychiatry Res 1990;31:267-78. PubMed
  14. Jangid P, Malik P, Singh P, Sharma M, Gulia AK. Comparative study of efficacy of l-5-hydroxytryptophan and fluoxetine in patients presenting with first depressive episode. Asian J Psychiatr 2013;6:29-34. PubMed
  15. Ceci F, Cangiano C, Cairella M, et al. The effects of oral 5-hydroxytryptophan administration on feeding behavior in obese adult female subjects. J Neural Transm 1989;76:109-17. PubMed
  16. Angst J, Woggon B, Schoepf J. The treatment of depression with L-5-hydroxytryptophan versus imipramine. Results of two open and one double-blind study. Arch Psychiatr Nervenkr 1977;224:175-86. DOI
  17. Titus F, Dávalos A, Alom J, Codina A. 5-Hydroxytryptophan versus methysergide in the prophylaxis of migraine. Randomized clinical trial. Eur Neurol 1986;25:327-9. PubMed
  18. De Benedittis G, Massei R. Serotonin precursors in chronic primary headache. A double-blind cross-over study with L-5-hydroxytryptophan vs. placebo. J Neurosurg Sci 1985;29:239-48.
  19. Van Woert, M. H., Rosenbaum, D., Howieson, J., and Bowers, M. B., Jr. Long-term therapy of myoclonus and other neurologic disorders with L-5- hydroxytryptophan and carbidopa. N Engl J Med 1-13-1977;296(2):70-75. PubMed
  20. Wyatt, R. J., Vaughan, T., Galanter, M., Kaplan, J., and Green, R. Behavioral changes of chronic schizophrenic patients given L-5- hydroxytryptophan. Science 9-22-1972;177(54):1124-1126. PubMed
  21. Chase, T. N., Ng, L. K., and Watanabe, A. M. Parkinson's disease. Modification by 5-hydroxytryptophan. Neurology 1972;22(5):479-484.
  22. van Hiele LJ. l-5-Hydroxytryptophan in depression: the first substitution therapy in psychiatry? The treatment of 99 out-patients with 'therapy-resistant' depressions. Neuropsychobiology 1980;6:230-40. PubMed
  23. Pranzatelli, M. R., Tate, E., Huang, Y., Haas, R. H., Bodensteiner, J., Ashwal, S., and Franz, D. Neuropharmacology of progressive myoclonus epilepsy: response to 5- hydroxy-L-tryptophan. Epilepsia 1995;36(8):783-791. PubMed
  24. Trouillas P, Serratrice G, Laplane D, et al. Levorotatory form of 5-hydroxytryptophan in Friedreich's ataxia. Results of a double-blind drug-placebo cooperative study. Arch Neurol 1995;52:456-60. PubMed
  25. Bastard, J., Truelle, J. L., and Emile, J. [Effectiveness of 5 hydroxy-tryptophan in Parkinson's disease]. Nouv Presse Med 9-11-1976;5(29):1836-1837.
  26. Auffret, M., Comte, H., and Bene, J. Eosinophilia-myalgia syndrome induced by L-5 hydroxytryptophane: about three cases. Fund Clin Pharmacol 2013;Suppl 1(120):poster P2-204.
  27. Wyatt, R. J., Vaughan, T., Kaplan, J., Galanter, M., and Green, R. 5-Hydroxytryptophan and chronic schizophrenia. In: Barchas J and Usdin E. Serotonin and Behavior. New York: Acedemic Press;1973.
  28. Das YT, Bagchi M, Bagchi D, Preuss HG. Safety of 5-hydroxy-L-tryptophan. Toxicol Lett 2004;150:111-22. PubMed
  29. Pardo JV. Mania following addition of hydroxytryptophan to monoamine oxidase inhibitor. Gen Hosp Psychiatry 2012;34(1):102.e13-4. PubMed
  30. Michelson D, Page SW, Casey R, et al. An eosinophilia-myaligia syndrome related disorder associated with exposure to l-5-hydroxytryptophan. J Rheumatol 1994;21(12):2261-5.
  31. Yousefzadeh F, Sahebolzamani E, Sadri A, et al. 5-Hydroxytryptophan as adjuvant therapy in treatment of moderate to severe obsessive-compulsive disorder: a double-blind randomized trial with placebo control. Int Clin Psychopharmacol. 2020;35(5):254-262. PubMed
  32. Maffei ME. 5-Hydroxytryptophan (5-HTP): Natural Occurrence, Analysis, Biosynthesis, Biotechnology, Physiology and Toxicology. Int J Mol Sci. 2020;22(1):181. PubMed

See these in context on the 5-htp monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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