L-Tyrosine 1 g Unflavored Ingredients & Drug Interactions
by Nutricost
What is this page for?
First and foremost: checking L-Tyrosine 1 g Unflavored 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
L-Tyrosine 1 g Unflavored is a dietary supplement by Nutricost 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.
Check Your Meds Against L-Tyrosine 1 g Unflavored by Nutricost
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Tyrosine 1 g Unflavored by Nutricost — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of L-Tyrosine 1 g Unflavored by Nutricost
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.
What’s inside
Full disclosure
This product contains a single active ingredient: L-tyrosine, an amino acid your body naturally produces and uses to make neurotransmitters (brain chemicals) and thyroid hormones. It's sold as an unflavored powder so you can mix it into drinks or food.
There are no other inactive ingredients listed.
Does it work?
Strong evidence
The evidence varies by use. L-tyrosine is effective for a rare genetic condition called phenylketonuria (PKU).
For cognitive function and memory, the evidence suggests it's possibly effective — the data points to some benefit but isn't conclusive. For athletic performance, the evidence suggests it's possibly ineffective.
For alcohol use disorder and dementia, there isn't enough reliable evidence to rate how well it works.
How safe is it?
Well-documented data
L-tyrosine is generally well tolerated in healthy adults. The most common side effects in trials were fatigue, headache, heartburn, and nausea.
Larger doses (around 150 mg per kilogram of body weight) are more likely to trigger headache and fatigue. No serious adverse effects have been documented, though a complete safety review hasn't been done.
Because safety data is limited, talk with a healthcare provider before regular use, and avoid supplemental doses unless a doctor recommends them. There isn't enough data on safety during pregnancy and breastfeeding; discuss this with your doctor or pharmacist if you're pregnant, planning to become pregnant, or nursing.
Meds to double-check
Moderate interaction found
Check with your pharmacist if you take levodopa (for Parkinson's disease) or thyroid hormone medications like levothyroxine — both have Moderate-severity interactions with this product. The rest of the 21 individual medications these ingredients may interact with should also be verified using the search tool below.
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 cognitive function and memory, and it's a confirmed treatment for PKU. If you take levodopa or thyroid hormones, you'll need to be careful — check your medications with the tool on this page.
Talk to your pharmacist before starting, especially if you're pregnant, nursing, or on any regular medications.
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 Oct 24, 2024.
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
General information
Key facts about L-Tyrosine 1 g Unflavored, straight from the product label.
| Brand | Nutricost |
|---|---|
| Barcode (UPC) | 702669930871 |
| Net contents | 3.5 Ounce(s); 100 Gram(s) |
| Market status | On market |
| Date entered into DSLD | Oct 24, 2024 |
| DSLD ID | 306327 |
| Product type | Amino Acid/protein |
| Supplement form | Powder |
| Dietary claims / uses | Nutrient, All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Gluten Free |
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 1 g Unflavored by Nutricost, sourced from the NIH Dietary Supplement Label Database.
Tap any ingredient to jump to its full detail below.
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions
Suggested use: As a dietary supplement, mix 1 scoop with 6-10 oz of water or as directed by your healthcare professional.
Formulation
Third party tested
Gluten-free
Non-GMO product
Made and quality tested in the USA with globally sourced ingredients.
Precautions
Warning: For healthy individuals 18 years and older.
Consult a healthcare professional prior to use if you are pregnant or nursing, taking medication, or have a medical condition.
Keep out of reach of children.
Do not use if safety seal is broken or missing.
Storage
Notice: Store in a cool, dry place.
General Statements
Contents are sold by weight, not volume. Some settling may occur.
Formula
L-Tyrosine 1 g per serving 100 g per container
FDA Statement of Identity
Dietary Supplement
Seals/Symbols
Nutricost Quality Guaranteed Third Party Tested
FDA Disclaimer Statement
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Tyrosine 1 g Unflavored by Nutricost label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in L-Tyrosine 1 g Unflavored by Nutricost
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Gram(s) Dosage formPowder Servings per container100 Amounts shown are per serving.
L-Tyrosine
Interacts with21 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 performan...
L-Tyrosine monograph & interactionsOther (inactive) ingredients: None. These complete the product’s ingredient list but are not active constituents.
L-Tyrosine 1 g Unflavored by Nutricost Drug Interactions
HelloPharmacist Interaction Report
L-Tyrosine by Nutricost can interact with two important medication types.
The most serious concern is with levodopa (used for Parkinson's disease), a Moderate-severity interaction: tyrosine and levodopa both use the same absorption pathway in your small intestine, and tyrosine may reduce how well levodopa works. If you take levodopa, separate your tyrosine dose by at least 2 hours.
Read the full breakdown — every affected drug type, severity by severity
Thyroid hormone medications (like levothyroxine) also pose a Moderate-severity interaction. Since tyrosine is a building block your body uses to make thyroid hormones, taking supplemental tyrosine might boost your thyroid hormone levels too much, potentially adding to the medication's effect.
Ensure you check your exact medications with the search tool on this page before starting.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Tyrosine 1 g Unflavored?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in L-Tyrosine 1 g Unflavored interact with 21 drugs. Click any drug to see the details.
1 of the 1 ingredient in L-Tyrosine 1 g Unflavored interact with drugs. Each result below shows which ingredient is responsible. L-Tyrosine
Benserazide, LevodopaMadopar, Prolopa
How Benserazide, Levodopa interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineLevodopa Moderate
Interaction Summary
Theoretically, tyrosine might decrease the effectiveness of levodopa.
Read the full L-tyrosine + Benserazide, Levodopa interactionCarbidopa, LevodopaDhivy, Rytary, Sinemet, Sinemet CR
How Carbidopa, Levodopa interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineLevodopa Moderate
Interaction Summary
Theoretically, tyrosine might decrease the effectiveness of levodopa.
Read the full L-tyrosine + Carbidopa, Levodopa interactionCarbidopa, Levodopa, EntacaponeStalevo
How Carbidopa, Levodopa, Entacapone interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineLevodopa Moderate
Interaction Summary
Theoretically, tyrosine might decrease the effectiveness of levodopa.
Read the full L-tyrosine + Carbidopa, Levodopa, Entacapone interactionConjugated EstrogensCenestin, Enjuvia, Premarin, Premarin Vaginal Cream
How Conjugated Estrogens interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Conjugated Estrogens interactionDesiccated Thyroid ExtractWesthroid, WP Thyroid
How Desiccated Thyroid Extract interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Desiccated Thyroid Extract interactionDesiccated Thyroid Extract (prescription Drug)Nature-Throid, Thyrar
How Desiccated Thyroid Extract (prescription Drug) interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Desiccated Thyroid Extract (prescription Drug) interactionDextrothyroxineCholoxin
How Dextrothyroxine interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Dextrothyroxine interactionHuman Chorionic Gonadotropin (hcg)Pregnyl
How Human Chorionic Gonadotropin (hcg) interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Human Chorionic Gonadotropin (hcg) interactionLevodopaInbrija, Larodopa
How Levodopa interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineLevodopa Moderate
Interaction Summary
Theoretically, tyrosine might decrease the effectiveness of levodopa.
Read the full L-tyrosine + Levodopa interactionLevodopa, CarbidopaDuodopa
How Levodopa, Carbidopa interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineLevodopa Moderate
Interaction Summary
Theoretically, tyrosine might decrease the effectiveness of levodopa.
Read the full L-tyrosine + Levodopa, Carbidopa interactionLevothyroxineEltroxin, Estre, Euthyrox, Levo-T, Levolet, Levothroid +5 more
How Levothyroxine interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Levothyroxine interactionLevothyroxine SodiumErmez, Thyquidity, Tirosint-Sol
How Levothyroxine Sodium interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Levothyroxine Sodium interactionLevothyroxine, LiothyronineArmour Thyroid
How Levothyroxine, Liothyronine interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Levothyroxine, Liothyronine interactionLiothyronineCytomel
How Liothyronine interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Liothyronine interactionLiotrixEuthroid 1, Euthroid 1/2, Euthroid 3
How Liotrix interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Liotrix interactionLiotrix, T4/t3Euthroid 2
How Liotrix, T4/t3 interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Liotrix, T4/t3 interactionMenotropinsMenopur, Repronex
How Menotropins interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Menotropins interactionOspemifeneOsphena
How Ospemifene interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Ospemifene interactionTestosterone UndecanoateAndriol, Aveed, Jatenzo, Kyzatrex
How Testosterone Undecanoate interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Testosterone Undecanoate interactionThyroglobulinProloid
How Thyroglobulin interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Thyroglobulin interactionThyroid HormoneEtwon
How Thyroid Hormone interacts with L-Tyrosine 1 g Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-tyrosineThyroid Hormone Moderate
Interaction Summary
Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Read the full L-tyrosine + Thyroid Hormone interactionEach ingredient & the kinds of drugs it affects
For each ingredient in L-Tyrosine 1 g Unflavored 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-Tyrosine
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.
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.
Brand information
Manufacturer and brand details for L-Tyrosine 1 g Unflavored, from the product label.
Nutricost
See all Nutricost products- Name
- Nutricost
- Street Address
- 351 E 1750 N
- City
- Vineyard
- State
- UT
- ZipCode
- 84059
- Phone Number
- (866) 438-3694
- Web Address
- www.nutricost.com
L-Tyrosine 1 g Unflavored by Nutricost: Common Questions
Does L-Tyrosine 1 g Unflavored by Nutricost interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
What does L-tyrosine actually do in my body?
Will this help my memory or thinking?
What side effects should I expect?
Is it safe to take while pregnant or breastfeeding?
Can I take this every day?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Tyrosine 1 g Unflavored is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
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.
The Full Monographs Behind L-Tyrosine 1 g Unflavored’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
L-Tyrosine 1 g Unflavored'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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
- 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.
- DiPiro JT, Talbert RL, Yee GC, et al; eds. Pharmacotherapy: A pathophysiologic approach. 4th ed. Stamford, CT: Appleton & Lange, 1999.
- Wood DR, Reimherr FW, Wender PH. Amino acid precursors for the treatment of attention deficit disorder, residual type. Psychopharmacol Bull 1985;21:146-9.
- van Spronsen FJ, van Rijn M, Bekhof J. Phenylketonuria: tyrosine supplementation in phenylalanine-restricted diets. Am J Clin Nutr 2001;73:153-7. PubMed
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