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Dietary supplement

L-Tyrosine Ingredients & Drug Interactions

by BulkSupplements.com

L-Tyrosine label
See full label image
Powder Category: Amino Acid/protein
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking L-Tyrosine 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

L-Tyrosine is a dietary supplement by BulkSupplements.com with 1 active ingredient. Its ingredients are commonly taken for mental focus and alertness, coping with stress, fatigue and sleep loss.Based on those ingredients, 21 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are L-Tyrosine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against L-Tyrosine by BulkSupplements.com

Ask about any prescription or over-the-counter medication and we check it for interactions with L-Tyrosine by BulkSupplements.com — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of L-Tyrosine by BulkSupplements.com

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

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 13, 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-tyrosine, an amino acid (a building block of protein) that your body uses to make several important compounds, including dopamine, norepinephrine, and thyroid hormones. The powder form makes it easy to measure and mix into drinks or food.

There are no inactive ingredients listed.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed

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

Strong

Strong clinical evidence supports Tyrosine 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: Phenylketonuria (PKU) — rated "Effective" (Natural Medicines).
  • On file: Cognitive function — rated "Possibly Effective" (Natural Medicines).
  • On file: Memory — rated "Possibly Effective" (Natural Medicines).

L-Tyrosine is effective for phenylketonuria (PKU), a rare genetic condition in which your body can't process the amino acid phenylalanine. For cognitive function and memory, the evidence suggests it's possibly effective — meaning some research points in that direction, but we don't have enough solid data yet to be certain.

For athletic performance, it appears to be possibly ineffective. The evidence isn't established for alcohol use disorder or dementia.

The evidence, ingredient by ingredient Tyrosine

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.

L-Tyrosine is generally well tolerated in healthy adults, but the safety data isn't complete, so talk with your healthcare provider before taking it regularly. The most common side effects from oral use are fatigue, headache, heartburn, and nausea — most often seen at higher doses (around 150 mg per kilogram of body weight).

If you combine it with other supplements like 5-hydroxytryptophan and carbidopa, you may experience drowsiness, agitation, diarrhea, or vomiting, though these effects usually improve if you lower the dose. There isn't enough safety data on file for pregnancy or while breastfeeding — talk with your doctor or pharmacist about whether this supplement is right for you in those situations.

Side effects, ingredient by ingredient Tyrosine

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 — Tyrosine.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: Parkinson's medications.
  • For scale: 21 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 L-Tyrosine, double-check with your doctor or pharmacist if you take levodopa (a Moderate interaction — tyrosine may reduce how well it works, so doses need to be spaced at least 2 hours apart) or thyroid hormone medications (also Moderate — tyrosine could add to their effect on your thyroid levels).

Check your own medication Run your meds through the checker above

The bottom line

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

L-Tyrosine may help with cognition and memory, and it's well tolerated by most people, but it isn't right for everyone. If you take levodopa or thyroid medications, you'll need to check with your doctor or pharmacist before starting — timing matters.

It's also worth talking things over with your healthcare provider before using it regularly, especially if you're pregnant, breastfeeding, or taking other supplements.

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 Sep 24, 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 L-Tyrosine, straight from the product label.

Brand BulkSupplements.com
Barcode (UPC) X000HSSKD5
Net contents 100 Gram(s); 3.5 oz
Market status On market
Date entered into DSLD Sep 24, 2021
DSLD ID 254841
Product type Amino Acid/protein
Supplement form Powder
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), 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 L-Tyrosine by BulkSupplements.com, 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:
500 mg
Maximum serving Sizes:
500 mg
Servings per container
200
UPC/BARCODE
X000HSSKD5
IngredientAmount% DV
L-Tyrosine500 mg--

Other ingredients: None

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

Clean & pure bulk supplements

FDA Disclaimer Statement

Warning: This product is not intended to diagnose, treat, cure, or prevent any disease.

Precautions

Always consult a physician before taking any dietary supplement.

Keep out of reach of children.

Formulation

Free of: Added sugar, soy, dairy, yeast, gluten, additives

Suggested/Recommended/Usage/Directions

Suggested use: As a dietary supplement, take 500 mg (about 1/5 tsp) one to three times daily, or as directed by a physician.

Storage

Store in a dry, cool place

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

See for yourself

L-Tyrosine by BulkSupplements.com label

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

L-Tyrosine 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 L-Tyrosine by BulkSupplements.com

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

Serving size500 mg Dosage formPowder Servings per container200 Amounts shown are per serving.

L-Tyrosine

Interacts with
21 drugs
500 mg per serving

L-tyrosine is an amino acid your body uses to make brain chemicals like dopamine and norepinephrine. Some studies suggest it may help mental performan...

L-Tyrosine monograph & interactions

Other (inactive) ingredients: None. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Tyrosine by BulkSupplements.com Drug Interactions

Want to check YOUR meds against L-Tyrosine?

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
21Drugs
21 Moderate

Ingredients driving the most interactions

L-Tyrosine 21

Individual Drug Interactions

The ingredients in L-Tyrosine interact with 21 drugs. Click any drug to see the details.

1 of the 1 ingredient in L-Tyrosine interact with drugs. Each result below shows which ingredient is responsible. L-Tyrosine

Each ingredient & the kinds of drugs it affects

For each ingredient in L-Tyrosine 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-Tyrosine2 drug types · 21 drugs

Levodopa

Theoretically, tyrosine might decrease the effectiveness of levodopa.
Tyrosine and levodopa compete for absorption in the proximal duodenum by the large neutral amino acid (LNAA) transport system. Advise patients to separate doses of tyrosine and levodopa by at least 2 hours.

Likelihood Probable Evidence D
Thyroid Hormone

Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Tyrosine is a precursor to thyroxine and might increase levels of thyroid hormones.

Likelihood Probable Evidence D
L-Tyrosine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for L-Tyrosine, from the product label.

BulkSupplements.com

See all BulkSupplements.com products
Name
BulkSupplements.com
Street Address
7511 Eastgate Rd
City
Henderson
State
NV
ZipCode
89011
Web Address
BulkSupplements.com
Pharmacist Counseling Corner

L-Tyrosine by BulkSupplements.com: Common Questions

Does L-Tyrosine by BulkSupplements.com interact with any medications?
Yes. Based on its ingredients, L-Tyrosine has a known interaction with 21 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
L-Tyrosine 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.
What is L-tyrosine used for?
L-tyrosine is an amino acid your body uses to make dopamine, norepinephrine, and thyroid hormones. It's proven effective for phenylketonuria (PKU), a rare genetic condition, and there's some evidence it may help with cognitive function and memory, though the evidence isn't definitive yet.
What are the side effects?
Most people tolerate it well. The most common side effects are fatigue, headache, heartburn, and nausea, usually at higher doses. Taking it with certain other supplements (like 5-hydroxytryptophan or carbidopa) can cause drowsiness, agitation, diarrhea, or vomiting — effects that often improve by lowering the dose.
Is it safe during pregnancy or breastfeeding?
There isn't enough safety data on file to know either way. Talk with your doctor or pharmacist before taking L-tyrosine if you're pregnant or breastfeeding — they can give you personalized advice based on your situation.
Can I take this with my Parkinson's medication?
If you take levodopa, you'll need to be careful. Tyrosine and levodopa compete for absorption, so tyrosine might make the medication less effective. Talk with your doctor or pharmacist — they may recommend spacing the doses at least 2 hours apart.
Does it work for weight loss or energy?
The evidence on athletic performance suggests it's probably not effective for that purpose. While tyrosine is involved in making dopamine and other compounds that affect mood and energy, the data we hold doesn't establish it as an effective supplement for weight loss or general energy.
What's in the powder besides L-tyrosine?
There are no inactive ingredients listed — it's pure L-tyrosine powder with nothing else added.

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

Not sure if L-Tyrosine 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.

L-Tyrosine label
Go deeper

The Full Monographs Behind L-Tyrosine’s Ingredients

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

Herb & supplement monograph

Tyrosine

Interacts with 21 drugs

L-tyrosine is an amino acid your body uses to make brain chemicals like dopamine and norepinephrine. Some studies suggest it may help mental performance during short-term stress, sleep loss,...

Read the full Tyrosine monograph →
Sources

Sources & How We Checked

L-Tyrosine'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 4 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.

Tyrosine 4 references
  1. Meyer JS, Welch KM, Deshmukh VD, et al. Neurotransmitter precursor amino acids in the treatment of multi-infarct dementia and Alzheimer's disease. J Amer Geriat Soc 1977;25:289-98.
  2. DiPiro JT, Talbert RL, Yee GC, et al; eds. Pharmacotherapy: A pathophysiologic approach. 4th ed. Stamford, CT: Appleton & Lange, 1999.
  3. Wood DR, Reimherr FW, Wender PH. Amino acid precursors for the treatment of attention deficit disorder, residual type. Psychopharmacol Bull 1985;21:146-9.
  4. van Spronsen FJ, van Rijn M, Bekhof J. Phenylketonuria: tyrosine supplementation in phenylalanine-restricted diets. Am J Clin Nutr 2001;73:153-7. PubMed

See these in context on the Tyrosine 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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