Major interaction on record — check this product against your medications before combining. Based on 8 of 17 ingredients. Check your meds →
Dietary supplement

GenFX Ingredients & Drug Interactions

by Leading Edge Health

GenFX label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking GenFX 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: Major

GenFX is a dietary supplement by Leading Edge Health with 17 active ingredients. Its ingredients are commonly taken for muscle recovery and sports performance, gut health and 'leaky gut', recovery from severe illness or injury.Based on those ingredients, 488 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are L-Arginine, L-Glutamine, L-Tyrosine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against GenFX by Leading Edge Health

Ask about any prescription or over-the-counter medication and we check it for interactions with GenFX by Leading Edge Health — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of GenFX by Leading Edge Health

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 17 of its 17 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

GenFX contains 17 ingredients total. The active amino acids are L-glutamine, L-leucine, L-arginine, L-isoleucine, L-methionine, L-tyrosine, L-phenylalanine, L-valine, L-glycine, L-threonine, and L-lysine — building blocks your body uses for protein synthesis, neurotransmitter production, and tissue repair.

It also includes Panax ginseng powder, L-pyroglutamate, phytosterol complex, and extracts of hypothalamus, soy phospholipids, and anterior pituitary — ingredients marketed to support hormone balance and energy. The product also contains inactive ingredients: gelatin (the capsule shell), magnesium stearate (a flow agent), and silicon dioxide (an anti-caking agent).

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: HGH releaser to restore youthfulness.
  • We looked for evidence on: Aging, Aging skin, Athletic performance, Cognitive function, Depression, Exercise-induced muscle damage — and 4 related terms.
  • The strongest evidence on file: Tyrosine is rated "Possibly Effective" for Cognitive function (Natural Medicines).
  • Also on file: Tyrosine is rated "Possibly Effective" for Memory.
  • Also on file: Glutamine is rated "Possibly Ineffective" for Athletic performance.

The evidence for GenFX's ingredients is mixed. L-glutamine is effective for sickle cell disease and possibly effective for HIV/AIDS-related wasting, postoperative recovery, and critical illness recovery.

L-tyrosine is effective for phenylketonuria (PKU) and possibly effective for cognitive function and memory. L-lysine is possibly effective for cold sores.

L-phenylalanine is possibly effective for vitiligo but possibly ineffective for ADHD. L-glycine is possibly effective for schizophrenia.

L-methionine is possibly effective for neural tube birth defects. For the other amino acids and botanical extracts in this product — including their combined effects on general energy, growth, or hormone production — we hold no established effectiveness ratings in our data.

The evidence, ingredient by ingredient Glutamine L-arginine Methionine Tyrosine Phenylalanine Glycine Threonine Lysine

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 8 of the 8 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 8 of 8.
  • General safety write-ups exist for 8 of 8.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most of these amino acids are generally well tolerated in healthy adults. Common side effects from L-glutamine include belching, bloating, constipation, diarrhea, nausea, and gastrointestinal pain — especially at higher doses.

L-arginine may cause abdominal pain, bloating, nausea, diarrhea, headache, insomnia, and flushing. L-tyrosine can cause fatigue, headache, heartburn, and nausea.

L-phenylalanine may cause anxiety, constipation, headache, heartburn, insomnia, nausea, and sedation. L-lysine may cause abdominal pain, diarrhea, and indigestion.

Important cautions: L-glutamine should be used only under medical supervision if you have kidney or liver disease. L-arginine safety for self-treatment is not well established and should be used under medical guidance.

L-phenylalanine must be avoided by anyone with phenylketonuria (PKU). Pregnancy and breastfeeding safety varies by ingredient — L-glutamine and L-methionine are rated likely safe in pregnancy, but L-phenylalanine should be avoided in pregnancy and breastfeeding.

For L-tyrosine, L-glycine, L-threonine, and L-lysine, pregnancy and breastfeeding safety data are insufficient or not on file; talk with your doctor before use if you are pregnant or breastfeeding.

Side effects, ingredient by ingredient Glutamine L-arginine Methionine Tyrosine Phenylalanine Glycine Threonine Lysine

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 7 of the 8 matched ingredients can interact with medications — Lysine, Phenylalanine, L-arginine, Glutamine, Tyrosine, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; seizure medications; diabetes medications; Parkinson's medications.
  • For scale: 488 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 GenFX, check with your pharmacist if you take any of these: levodopa or other Parkinson medications (Major risk with L-phenylalanine, Moderate risk with L-tyrosine); NMDA antagonists like memantine or ketamine (Major risk with L-threonine); blood pressure medications, ACE inhibitors, ARBs, or diuretics (Moderate risk with L-arginine); blood thinners or antiplatelet drugs like warfarin or aspirin (Moderate risk with L-arginine); diabetes medications (Moderate risk with L-arginine); MAOIs (Moderate risk with L-phenylalanine); baclofen (Moderate risk with L-phenylalanine); anticonvulsants like phenytoin (Moderate risk with L-glutamine); clozapine (Moderate risk with L-glycine); thyroid hormone medications (Moderate risk with L-tyrosine); or medications for IBS or nausea that are 5-HT4 agonists (Minor risk with L-lysine). No interactions are documented for the ingredients we could not check.

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. Major medication interactions have been identified, and safety information is well characterized.

GenFX is an amino acid supplement that may appeal to people interested in muscle support, recovery, or cognitive function — but it carries serious medication interactions you need to check first, especially if you take Parkinson medications, blood pressure drugs, blood thinners, diabetes medications, or MAOIs. People with PKU must avoid this product entirely because of L-phenylalanine.

If you are pregnant, breastfeeding, or have kidney or liver disease, talk with your pharmacist or doctor before starting.

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

Assessment coverage: 8 of 17 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Aug 22, 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 GenFX, straight from the product label.

Brand Leading Edge Health
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Aug 22, 2025
DSLD ID 336110
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
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 GenFX by Leading Edge Health, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
30
IngredientAmount% DV
L-Glutamine200 mg--
L-Leucine2.86 mg--
L-Arginine200 mg--
L-Isoleucine2.86 mg--
L-Methionine2.86 mg--
L-Tyrosine200 mg--
L-Phenylalanine2.86 mg--
L-Valine2.86 mg--
L-Glycine200 mg--
L-Threonine2.86 mg--
L-Lysine202.86 mg--
Panax ginseng, Powder80 mg--
L-Pyroglutamate200 mg--
Phytosterol Complex40 mg--
Hypothalamus40 mg--
Soy Phosphotides Complex80 mg--
Anterior Pituitary40 mg--

Other ingredients: Gelatin, Magnesium Stearate, Silicon Dioxide

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

Restore youthfulness today HGH Releaser

FDA Statement of Identity

Dietary Supplement with Amino Acids

Suggested/Recommended/Usage/Directions

Recommended use As a nutritional supplement take one capsule twice daily with a meal and a full glass of water.

Precautions

Keep out of reach of children.

Storage

Store in a dry cool place.

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.

Formula

Dietary Supplement with Amino Acids

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

See for yourself

GenFX by Leading Edge Health label

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

GenFX 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 GenFX by Leading Edge Health

These are the 17 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container30 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

L-Glutamine

Interacts with
50 drugs
200 mg per serving

Glutamine is the most abundant amino acid in the body and is usually made in your muscles. A prescription form is FDA-approved to help reduce sickle c...

L-Glutamine monograph & interactions

L-Leucine

2.86 mg per serving

L-Arginine

Interacts with
403 drugs
200 mg per serving

L-arginine is an amino acid that the body uses to make nitric oxide, a substance that helps blood vessels relax and widen. It is popularly used for bl...

L-Arginine monograph & interactions

L-Isoleucine

2.86 mg per serving

L-Methionine

No known
interactions
2.86 mg per serving

Methionine is an essential amino acid that your body needs for protein building and many basic chemical reactions. Most people get enough from a norma...

L-Methionine monograph & interactions

L-Tyrosine

Interacts with
21 drugs
200 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

L-Phenylalanine

Interacts with
16 drugs
2.86 mg per serving

Phenylalanine is an essential amino acid the body uses to make brain chemicals like dopamine and norepinephrine. Some people take it for mood, vitilig...

L-Phenylalanine monograph & interactions

L-Valine

2.86 mg per serving

L-Glycine

Interacts with
1 drug
200 mg per serving

Glycine is a non-essential amino acid your body makes on its own and that also appears in protein-rich foods. It is most studied for improving sleep q...

L-Glycine monograph & interactions

L-Threonine

Interacts with
3 drugs
2.86 mg per serving

Threonine is an essential amino acid your body needs but cannot make, so you must get it from food or supplements. Most people get plenty from a norma...

L-Threonine monograph & interactions

L-Lysine

Interacts with
1 drug
202.86 mg per serving

Lysine is an essential amino acid your body cannot make on its own, so it must come from food or supplements. People most often take extra lysine to t...

L-Lysine monograph & interactions

Panax ginseng, Powder

80 mg per serving

L-Pyroglutamate

200 mg per serving

Phytosterol Complex

40 mg per serving

Hypothalamus

40 mg per serving

Soy Phosphotides Complex

80 mg per serving

Anterior Pituitary

40 mg per serving

Other (inactive) ingredients: Gelatin, Magnesium Stearate, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

GenFX by Leading Edge Health Drug Interactions

Want to check YOUR meds against GenFX?

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
488Drugs
8 Major 472 Moderate 8 Minor

Ingredients driving the most interactions

L-Arginine 403
L-Glutamine 50
L-Tyrosine 21
L-Phenylalanine 16
L-Threonine 3

Individual Drug Interactions

The ingredients in GenFX interact with 488 drugs. Click any drug to see the details.

7 of the 17 ingredients in GenFX interact with drugs. Each result below shows which ingredient is responsible. L-Arginine L-Glutamine L-Tyrosine L-Phenylalanine L-Threonine L-Glycine L-Lysine

Each ingredient & the kinds of drugs it affects

For each ingredient in GenFX 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-Arginine9 drug types · 403 drugs

Ace Inhibitors (Aceis)

Theoretically, concomitant use of L-arginine and ACE inhibitors may increase the risk for hypotension and hyperkalemia.
Combining L-arginine with some antihypertensive drugs, especially ACE inhibitors, seems to have additive vasodilating and blood pressure-lowering effects. Furthermore, ACE inhibitors can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients. Theoretically, concomitant use of ACE inhibitors with L-arginine may increases the risk of hyperkalemia.

Likelihood Probable Evidence D
Angiotensin Receptor Blockers (Arbs)

Theoretically, concomitant use of L-arginine and ARBs may increase the risk of hypotension and hyperkalemia.
L-arginine increases nitric oxide, which causes vasodilation. Combining L-arginine with ARBs seems to increase L-arginine-induced vasodilation. Furthermore, ARBs can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients. Theoretically, concomitant use of ARBs with L-arginine may increases the risk of hyperkalemia.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, concomitant use of L-arginine with anticoagulant and antiplatelet drugs might have additive effects and increase the risk of bleeding.
Preliminary research suggests that L-arginine infusions reduce platelet aggregation in humans. The clinical significance of this effect is unclear.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, concomitant use of L-arginine might have additive effects with antidiabetes drugs.
Preliminary clinical research shows that L-arginine decreases blood glucose levels in patients with type 2 diabetes.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, concomitant use of L-arginine and antihypertensive drugs may increase the risk of hypotension.
L-arginine increases nitric oxide, which causes vasodilation. Clinical evidence shows that L-arginine can reduce blood pressure in some individuals with hypertension. Furthermore, combining L-arginine with some antihypertensive drugs seems to have additive vasodilating and blood pressure-lowering effects.

Likelihood Probable Evidence D
Isoproterenol (Isuprel)

Theoretically, concurrent use of isoproterenol and L-arginine might result in additive effects and hypotension.
Preliminary clinical evidence suggests that L-arginine enhances isoproterenol-induced vasodilation in patients with essential hypertension or a family history of essential hypertension.

Likelihood Probable Evidence D
Potassium-Sparing Diuretics

Theoretically concomitant use of potassium-sparing diuretics with L-arginine may increases the risk of hyperkalemia.
Potassium-sparing diuretics can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients.

Likelihood Possible Evidence D
Sildenafil (Viagra)

Theoretically, concurrent use of sildenafil and L-arginine might increase the risk for hypotension.
In vivo, concurrent use of L-arginine and sildenafil has resulted in increased vasodilation. Theoretically, concurrent use might have additive vasodilatory and hypotensive effects. However, in studies evaluating the combined use of L-arginine and sildenafil for erectile dysfunction, hypotension was not reported.

Likelihood Possible Evidence D
Testosterone

Theoretically, concomitant use of L-arginine and testosterone might have additive effects.
In clinical research, L-arginine increases the level of testosterone in male patients with erectile dysfunction. The clinical significance of this finding is unclear.

Likelihood Possible Evidence D
L-Arginine full monograph & interactions

L-Glutamine1 drug type · 50 drugs

Anticonvulsants

Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Glutamine is metabolized to the excitatory neurotransmitter glutamate. Glutamate might have antagonistic effects with anticonvulsant drugs. However, this interaction has not yet been reported in humans.

Likelihood Possible Evidence D
L-Glutamine full monograph & interactions

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

L-Phenylalanine3 drug types · 16 drugs

Levodopa

Phenylalanine, especially in high doses, can reduce the effectiveness of levodopa.
Phenylalanine competes with levodopa for carrier-mediated transport into the brain. The resulting reduction in levels of levodopa in the brain can exacerbate tremor, rigidity, and the "on-off" phenomenon in patients with Parkinson disease.

Likelihood Probable Evidence B
Baclofen

Concomitant intake of phenylalanine may reduce the intestinal absorption of baclofen.
Phenylalanine and baclofen share the same intestinal carrier for absorption; phenylalanine competitively inhibits the absorption of baclofen, reducing its plasma levels.

Likelihood Possible Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use of L-phenylalanine and non-selective MAOIs might increase the risk of hypertensive crisis.
L-phenylalanine is metabolized to tyrosine. Some evidence suggests that L-phenylalanine, given with the non-selective MAOI pargyline, might prevent the elimination of tyramine, increasing the risk of hypertensive crisis. However, this was not reported in a small number of patients when using L-phenylalanine with the partially selective MAO-B inhibitor, selegiline.

Likelihood Possible Evidence D
L-Phenylalanine full monograph & interactions

L-Threonine1 drug type · 3 drugs

Nmda Antagonists

Theoretically, threonine might decrease the effects of NMDA antagonists.
Threonine increases central nervous system (CNS) glycine levels. Glycine seems to bind a site on NMDA receptors and enhance the activity of the receptors.

Likelihood Likely Evidence B
L-Threonine full monograph & interactions

L-Glycine1 drug type · 1 drug

Clozapine (Clozaril)

Theoretically, glycine might decrease the effectiveness of clozapine.
One small clinical study in patients with schizophrenia shows that adding glycine to clozapine therapy worsens symptoms of schizophrenia when compared with clozapine alone. The mechanism of this interaction is unclear.

Likelihood Probable Evidence B
L-Glycine full monograph & interactions

L-Lysine1 drug type · 1 drug

5-Ht4 Agonists

Theoretically, lysine may reduce the effects of 5-HT4 agonists.
Animal research suggests that L-lysine is a partial serotonin receptor 4 (5-HT4) antagonist and inhibits diarrhea induced by the 5-HT4 agonist, 5-hydroxytryptophane.

Likelihood Unlikely Evidence D
L-Lysine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for GenFX, from the product label.

Leading Edge Health

See all Leading Edge Health products
Name
Leading Edge Health
Street Address
c/o 100 Fidelitone Way
City
Elizabethton
State
TN
ZipCode
37643
Web Address
www.genfx.com
Pharmacist Counseling Corner

GenFX by Leading Edge Health: Common Questions

Does GenFX by Leading Edge Health interact with any medications?
Yes. Based on its ingredients, GenFX has a known interaction with 488 medications, including 8 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
GenFX contains 17 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 GenFX if I'm pregnant?
It depends on the ingredient. L-glutamine and L-methionine are rated likely safe in pregnancy, but L-phenylalanine should be avoided because safety hasn't been established. For the other amino acids and botanical ingredients, we don't have enough pregnancy safety data. Talk with your doctor or pharmacist for personalized advice before taking this product while pregnant.
Is GenFX safe while breastfeeding?
Safety data while breastfeeding are limited or not on file for most ingredients in this product. L-glutamine has some safety data supporting use, but L-phenylalanine should be avoided. For the others, there isn't enough information. Check with your pharmacist or doctor before use if you're breastfeeding.
What is L-arginine supposed to do?
L-arginine is an amino acid that increases nitric oxide in your body, which relaxes blood vessels and can lower blood pressure. It may also help with blood sugar control in type 2 diabetes and reduce platelet aggregation (clotting tendency), though the practical importance of these effects isn't fully clear. No formal effectiveness rating is established for it in our data.
Does L-lysine really help with cold sores?
Yes, L-lysine is rated possibly effective for cold sores (herpes labialis). It may help reduce the frequency or severity of outbreaks, though the evidence is not as strong as for some other treatments.
Can I take this if I have kidney or liver disease?
L-glutamine, one of the main ingredients, should be used only under medical supervision if you have kidney or liver disease. L-arginine safety for self-treatment is also not well established. Talk with your doctor or pharmacist before starting GenFX if you have either condition.
What are the most common side effects?
Gastrointestinal symptoms are most common: bloating, constipation, diarrhea, nausea, and abdominal pain — especially from L-glutamine and L-arginine at higher doses. Headache, fatigue, heartburn, and nausea can also occur. Most of these are mild and dose-dependent.

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

Not sure if GenFX is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.

GenFX label
Go deeper

The Full Monographs Behind GenFX’s Ingredients

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

Herb & supplement monograph

Glutamine

Interacts with 50 drugs

Glutamine is the most abundant amino acid in the body and is usually made in your muscles. A prescription form is FDA-approved to help reduce sickle cell disease complications, but for most...

Read the full Glutamine monograph → Herb & supplement monograph

L-arginine

Interacts with 403 drugs

L-arginine is an amino acid that the body uses to make nitric oxide, a substance that helps blood vessels relax and widen. It is popularly used for blood pressure, erectile dysfunction, and...

Read the full L-arginine monograph → Herb & supplement monograph

Methionine

Methionine is an essential amino acid that your body needs for protein building and many basic chemical reactions. Most people get enough from a normal diet, and supplements are generally no...

Read the full Methionine monograph → 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 → Herb & supplement monograph

Phenylalanine

Interacts with 16 drugs

Phenylalanine is an essential amino acid the body uses to make brain chemicals like dopamine and norepinephrine. Some people take it for mood, vitiligo, or pain, but the evidence is mostly l...

Read the full Phenylalanine monograph → Herb & supplement monograph

Glycine

Interacts with 1 drug

Glycine is a non-essential amino acid your body makes on its own and that also appears in protein-rich foods. It is most studied for improving sleep quality, where early research is promisin...

Read the full Glycine monograph → Herb & supplement monograph

Threonine

Interacts with 3 drugs

Threonine is an essential amino acid your body needs but cannot make, so you must get it from food or supplements. Most people get plenty from a normal diet, and high-quality evidence for ta...

Read the full Threonine monograph → Herb & supplement monograph

Lysine

Interacts with 1 drug

Lysine is an essential amino acid your body cannot make on its own, so it must come from food or supplements. People most often take extra lysine to try to prevent or shorten cold sores, but...

Read the full Lysine monograph →
Sources

Sources & How We Checked

GenFX'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 132 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.

Glutamine 11 references
  1. Miller AL. Therapeutic considerations of L-glutamine: a review of the literature. Altern Med Rev 1999;4:239-48..
  2. Bozzetti F, Biganzoli L, Gavazzi C, et al. Glutamine supplementation in cancer patients receiving chemotherapy: a double-blind randomized study. Nutrition 1997;13:748-51.. PubMed
  3. Mebane AH. L-Glutamine and mania. Am J Psychiatry 984;141:1302-3.
  4. Meldrum BS. Glutamate as a neurotransmitter in the brain: review of physiology and pathology. J Nutr 2000;130:1007S-15S.. PubMed
  5. Garlick PJ. Assessment of the safety of glutamine and other amino acids. J Nutr 2001;131:2556S-61S.. PubMed
  6. Chapman AG. Glutamate and epilepsy. J Nutr 2000;130:1043S-5S.. PubMed
  7. Ziegler TR. Glutamine supplementation in cancer patients receiving bone marrow transplantation and high dose chemotherapy. J Nutr 2001;131:2578S-84S.. PubMed
  8. Laviano A, Molfino A, Lacaria MT, Canelli A, De Leo S, Preziosa I, Rossi Fanelli F. Glutamine supplementation favors weight loss in nondieting obese female patients. A pilot study. Eur J Clin Nutr. 2014 Nov;68(11):1264-6. PubMed
  9. Endari (l-glutamine) [package insert]. Torrance, CA: Emmaus Medical,Inc; 2017.
  10. Niihara Y, Miller ST, Kanter J, et al. A Phase 3 Trial of l-Glutamine in Sickle Cell Disease. N Engl J Med 2018;379(3):226-35. doi: 10.1056/NEJMoa1715971.
  11. Ogden HB, Child RB, Fallowfield JL, et al. Gastrointestinal Tolerance of Low, Medium and High Dose Acute Oral l-Glutamine Supplementation in Healthy Adults: A Pilot Study. Nutrients. 2020;12(10):2953. PubMed

See these in context on the Glutamine monograph →

L-arginine 66 references
  1. Sapienza MA, Kharitonov SA, Horvath I, et al. Effect of inhaled L-arginine on exhaled nitric oxide in normal and asthmatic subjects. Thorax 1998;53:172-5.
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Threonine 4 references
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Lysine 7 references
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