Major interaction on record — check this product against your medications before combining. Based on 17 of 21 ingredients. Check your meds →
Dietary supplement

Amino Acid Neurotransmitter Formula Ingredients & Drug Interactions

by Allergy Research Group

Amino Acid Neurotransmitter Formula label
See full label image
Powder 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 Amino Acid Neurotransmitter Formula 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

Amino Acid Neurotransmitter Formula is a dietary supplement by Allergy Research Group with 21 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, 912 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are L-Theanine, Lithium, GABA. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Amino Acid Neurotransmitter Formula by Allergy Research Group

Ask about any prescription or over-the-counter medication and we check it for interactions with Amino Acid Neurotransmitter Formula by Allergy Research Group — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Amino Acid Neurotransmitter Formula by Allergy Research Group

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 12, 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 21 of its 21 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This formula contains 21 ingredients, with 17 being amino acids — the building blocks your body uses to make proteins and neurotransmitters (chemical messengers in your brain and nervous system). The active amino acids are L-glutamine, glycine, L-leucine, L-arginine, L-alanine, L-isoleucine, L-methionine, L-tyrosine, L-phenylalanine, L-valine, L-histidine, L-threonine, L-lysine, L-serine, and L-cysteine, along with taurine, 5-HTP (a precursor to serotonin), L-theanine, GABA, and lithium.

The remaining ingredients are inactive: fiber gum acacia, lemon flavoring, xylitol, sweeteners, citric acid, and xanthan gum for texture.

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 its ingredients' overall clinical evidence instead.

Strong

Strong clinical evidence supports its ingredients 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 ingredients' overall clinical evidence instead.
  • On file: Phenylketonuria (PKU) — rated "Effective" (Tyrosine) (Natural Medicines).
  • On file: Sickle cell disease — rated "Effective" (Glutamine) (Natural Medicines).
  • On file: HIV/AIDS-related wasting — rated "Possibly Effective" (Glutamine) (Natural Medicines).
  • On file: Cholera — rated "Possibly Effective" (Histidine) (Natural Medicines).
  • On file: Cognitive function — rated "Possibly Effective" (Theanine) (Natural Medicines).

The evidence for this product'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.

L-tyrosine is effective for phenylketonuria (PKU) and possibly effective for cognitive function and memory. L-phenylalanine is possibly effective for vitiligo.

L-serine is possibly effective for schizophrenia. Taurine is possibly effective for hepatitis and congestive heart failure.

5-HTP is possibly effective for depression. L-theanine is possibly effective for cognitive function.

Glycine and L-lysine are possibly effective for schizophrenia and cold sores, respectively. However, evidence is insufficient or the product is possibly ineffective for many other claimed uses (such as ADHD, athletic performance, or general anxiety) — the data we hold simply doesn't support those claims.

The evidence, ingredient by ingredient Glutamine Glycine L-arginine Alpha-alanine Methionine Tyrosine Phenylalanine Histidine

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 14 of the 17 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 17 of 17.
  • General safety write-ups exist for 17 of 17.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most individual amino acids are generally well tolerated at typical doses, though side effects vary by ingredient. L-glutamine may cause belching, bloating, constipation, diarrhea, flatulence, nausea, and vomiting; high doses can cause dizziness or, in people with bipolar disorder, mania.

Glycine rarely causes mild sedation, nausea, or vomiting. L-arginine can cause abdominal pain, bloating, nausea, diarrhea, headache, and insomnia.

L-tyrosine may cause fatigue, headache, heartburn, and nausea. L-phenylalanine may cause anxiety, constipation, headache, heartburn, insomnia, nausea, and sedation.

5-HTP commonly causes abdominal pain, diarrhea, drowsiness, fatigue, headache, insomnia, and nausea; in rare cases, aggression, hallucinations, or mania. L-theanine may cause headaches or drowsiness.

GABA may cause drowsiness, gastric upset, and nausea. Taurine generally causes constipation, diarrhea, or dyspepsia.

Lithium requires blood-level monitoring when used as a prescription and carries a narrow safety margin; supplements have not been well studied. Pregnancy and lactation safety vary widely: L-glutamine, L-alanine, L-methionine, and L-cysteine are likely safe; L-phenylalanine is unsafe during pregnancy and lactation; L-serine and 5-HTP should be avoided in pregnancy and lactation due to insufficient data; L-tyrosine and L-lysine have insufficient safety data; and lithium is possibly unsafe in pregnancy and likely unsafe while breastfeeding.

Side effects, ingredient by ingredient Glutamine Glycine L-arginine Alpha-alanine Methionine Tyrosine Phenylalanine Histidine

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?
  • 13 of the 17 matched ingredients can interact with medications — Lysine, Gamma-aminobutyric Acid (gaba), Phenylalanine, 5-htp, L-arginine, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; seizure medications; diabetes medications; lithium; Parkinson's medications.
  • For scale: 912 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.

Major interactions: levodopa (L-phenylalanine), NMDA antagonists (L-threonine), serotonergic drugs combined with lithium, and diuretics with lithium. Moderate interactions: anticonvulsants (L-glutamine), clozapine (glycine), blood pressure medications (L-arginine, L-theanine, GABA, taurine), potassium-sparing diuretics (L-arginine), blood thinners (L-arginine), diabetes medications (L-arginine, L-cysteine), ACE inhibitors (L-arginine), ARBs (L-arginine), sildenafil (L-arginine), levodopa (L-tyrosine), thyroid hormones (L-tyrosine), baclofen (L-phenylalanine), MAOIs (L-phenylalanine), CNS depressants (5-HTP, L-theanine, GABA), 5-HT4 agonists (L-lysine), and lithium with NSAIDs, antipsychotics, ACE inhibitors, calcium channel blockers, anticonvulsants, and skeletal muscle relaxants.

Minor interactions: CNS depressants with L-theanine and GABA, and serotonergic drugs with L-theanine.

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

This is a complex multi-ingredient formula suited to people seeking amino acid and neurotransmitter support under professional guidance — but it carries serious interaction risks with common medications, especially blood pressure drugs, antidepressants, diabetes medications, and lithium-based treatments. If you take levodopa for Parkinson's, NMDA antagonists, prescription lithium, or any serotonergic medication, talk to your pharmacist before taking this product.

Even without those, check every medication you're on with the tool below.

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

Assessment coverage: 17 of 21 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Dec 23, 2015.

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 Amino Acid Neurotransmitter Formula, straight from the product label.

Brand Allergy Research Group
Barcode (UPC) 713947709706
Net contents 100 Gram(s)
Market status On market
Date entered into DSLD Dec 23, 2015
DSLD ID 54247
Product type Other Combinations
Supplement form Powder
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 Amino Acid Neurotransmitter Formula by Allergy Research Group, 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:
4 Gram(s)
Maximum serving Sizes:
4 Gram(s)
Servings per container
25
UPC/BARCODE
713947709706
IngredientAmount% DV
L-Glutamine750 mg--
Glycine300 mg--
L-Leucine185 mg--
L-Arginine80 mg--
L-Alanine111 mg--
L-Isoleucine185 mg--
L-Methionine37 mg--
L-Tyrosine100 mg--
L-Phenylalanine200 mg--
L-Valine74 mg--
L-Histidine Hydrochloride130 mg--
L-Threonine148 mg--
Alpha-Glucan Oligosaccharide166 mg--
L-Lysine259 mg--
L-Serine37 mg--
Taurine200 mg--
5-HTP25 mg--
L-Theanine50 mg--
GABA75 mg--
L-Cysteine Dihydrochloride37 mg--
Lithium2 mg--

Other ingredients: Fiber Gum Acacia, natural Lemon flavor, Xylitol, Megna Sweet, Stevia powder, Citric Acid, Xanthan Gum

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

Hypoallergenic

Suggested/Recommended/Usage/Directions

Suggested use As a dietary supplement, 1 level scoop (4 grams) per 6 ounces of water, or as directed by healthcare practitioner.

Storage

Keep in a cool, dry place, tightly capped.

FDA Statement of Identity

dietary supplement

Formula

Hypoallergenic

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

See for yourself

Amino Acid Neurotransmitter Formula by Allergy Research Group label

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

Amino Acid Neurotransmitter Formula 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 Amino Acid Neurotransmitter Formula by Allergy Research Group

These are the 21 active ingredients this product is made of. Select any to open its full monograph.

Serving size4 Gram(s) Dosage formPowder Servings per container25 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
750 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

Glycine

Interacts with
1 drug
300 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...

Glycine monograph & interactions

L-Leucine

185 mg per serving

L-Arginine

Interacts with
403 drugs
80 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-Alanine

No known
interactions
111 mg per serving

Alpha-alanine (usually called alanine) is a non-essential amino acid your body can make on its own and that you also get from protein foods. Most peop...

L-Alanine monograph & interactions

L-Isoleucine

185 mg per serving

L-Methionine

No known
interactions
37 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
100 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
200 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

74 mg per serving

L-Histidine Hydrochloride

No known
interactions
130 mg per serving

Histidine is an essential amino acid your body needs to build proteins and to make compounds like histamine and carnosine. Most people get enough from...

L-Histidine Hydrochloride monograph & interactions

L-Threonine

Interacts with
3 drugs
148 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

Alpha-Glucan Oligosaccharide

166 mg per serving

L-Lysine

Interacts with
1 drug
259 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

L-Serine

No known
interactions
37 mg per serving

Serine is an amino acid your body can make on its own and also gets from protein-rich foods, so most people do not need a supplement. L-serine has bee...

L-Serine monograph & interactions

Taurine

Interacts with
173 drugs
200 mg per serving

Taurine is an amino acid your body makes naturally and that you also get from animal foods. It is widely used in energy drinks and sports supplements,...

Taurine monograph & interactions

5-HTP

Interacts with
398 drugs
25 mg per serving

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...

5-HTP monograph & interactions

L-Theanine

Interacts with
565 drugs
50 mg per serving

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong dro...

L-Theanine monograph & interactions

GABA

Interacts with
419 drugs
75 mg per serving

GABA is a calming chemical messenger (neurotransmitter) that your body makes on its own, and it is sold as a supplement for stress, anxiety, and sleep...

GABA monograph & interactions

L-Cysteine Dihydrochloride

Interacts with
86 drugs
37 mg per serving

L-cysteine is a sulfur-containing amino acid your body uses to make proteins and the antioxidant glutathione. Most people get enough from food, and su...

L-Cysteine Dihydrochloride monograph & interactions

Lithium

Interacts with
515 drugs
2 mg per serving Form: Lithium Citrate

Lithium is a naturally occurring metal that, in prescription form (lithium carbonate or citrate), is an FDA-approved, well-proven treatment for bipola...

Lithium monograph & interactions

Other (inactive) ingredients: Fiber Gum Acacia, Natural Lemon flavor, Xylitol, Megna Sweet, Stevia powder, Citric Acid, Xanthan Gum. These complete the product’s ingredient list but are not active constituents.

Interaction report

Amino Acid Neurotransmitter Formula by Allergy Research Group Drug Interactions

Want to check YOUR meds against Amino Acid Neurotransmitter Formula?

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
912Drugs
267 Major 638 Moderate 7 Minor

Ingredients driving the most interactions

L-Theanine 565
Lithium 515
GABA 419
L-Arginine 403
5-HTP 398

Individual Drug Interactions

The ingredients in Amino Acid Neurotransmitter Formula interact with 912 drugs. Click any drug to see the details.

13 of the 21 ingredients in Amino Acid Neurotransmitter Formula interact with drugs. Each result below shows which ingredient is responsible. L-Theanine Lithium GABA L-Arginine 5-HTP Taurine L-Cysteine Dihydrochloride L-Glutamine L-Tyrosine L-Phenylalanine L-Threonine Glycine L-Lysine

Each ingredient & the kinds of drugs it affects

For each ingredient in Amino Acid Neurotransmitter Formula 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-Theanine3 drug types · 565 drugs

Antihypertensive Drugs

Theanine might lower blood pressure, potentiating the effects of antihypertensive drugs.
Animal research shows that theanine can lower blood pressure in spontaneously hypertensive animals. Theoretically, concomitant use of theanine and antihypertensive drugs might potentiate the antihypertensive activity.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, theanine might have additive sedative effects when used in conjunction with CNS depressants. However, it is unclear if this concern is clinically relevant.
Theoretically, theanine may compete with glutamate and/or increase plasma gamma-aminobutyric acid (GABA) levels, which could cause CNS depression. In one clinical study, some subjects taking oral theanine reported drowsiness.

Likelihood Unlikely Evidence D
Serotonergic Drugs

Clinical studies regarding the effects of L-theanine on serotonin levels are conflicting. Some studies suggest it can increase serotonin levels in the brain while others report that it may decrease them. Nevertheless, there have been no reports of l-theanine being a causative agent in serotonergic-related side effects or serotonin syndrome.

Likelihood Unlikely Evidence C
L-Theanine full monograph & interactions

Lithium11 drug types · 515 drugs

Diuretic Drugs

Theoretically, taking lithium supplements with loop diuretics might increase lithium levels and adverse effects.
Thiazide diuretics and loop diuretics might reduce lithium excretion, particularly in sodium-restricted patients. If lithium is clinically indicated and other treatment options are unavailable or inadequate in patients using diuretics, lithium treatment can be initiated with extreme caution. Serum lithium should be measured frequently and the doses used should be the lowest dose ordinarily tolerated. It is unclear if this interaction would be clinically significant with the smaller doses found in lithium supplements.

Likelihood Probable Evidence D
Serotonergic Drugs

Theoretically, taking lithium supplements with serotonergic drugs might both mask and increase the risk of serotonin syndrome.
In a case report, a 67-year-old female with depression and bipolar disorder using lithium in combination with selective serotonin reuptake inhibitors (SSRIs) and other medications developed serotonin syndrome with symptoms of deep tendon hyperreflexia, muscle rigidity, tremor, and hyperthermia. However, agitation, one classical symptom of serotonin syndrome, was lacking. This was thought to be due to masking by lithium toxicity. Lithium can increase serotonin levels, thus, combining serotonergic drugs with lithium might increase the risk of serotonergic side effects including serotonin syndrome and cerebral vasoconstrictive disorders. It is unclear if this interaction would occur with the smaller doses found in lithium supplements.

Likelihood Probable Evidence D
Ace Inhibitors (Aceis)

Theoretically, taking lithium supplements with ACEIs might increase levels and adverse effects of lithium.
Concomitant administration of ACEIs with lithium may increase lithium concentrations. It is unclear if this interaction would be clinically significant with the smaller doses found in lithium supplements.

Likelihood Possible Evidence D
Anticonvulsants

Theoretically, taking lithium supplements with anticonvulsants might increase the risk of neurotoxicity.
Drugs such as carbamazepine and phenytoin seem to increase the risk of neurotoxicity. It is unclear if this interaction would occur with the smaller doses found in lithium supplements.

Likelihood Possible Evidence D
Antipsychotic Drugs

Theoretically, taking lithium supplements with antipsychotic drugs might increase the risk of encephalopathic syndrome.
Encephalopathic syndrome has been reported in multiple patients taking prescription lithium and antipsychotics concomitantly. Symptoms have included weakness and lethargy, fever, confusion, and extrapyramidal symptoms. In some patients, resulting brain damage was irreversible. Although there is no established causal relationship between these symptoms and the combination of lithium and antipsychotic medications, there is a theoretical relationship. It is unclear if this interaction would occur with the smaller doses found in lithium supplements.

Likelihood Possible Evidence D
Calcium Channel Blockers

Theoretically, taking lithium supplements with calcium channel blockers might reduce lithium levels and might also increase the risk of certain adverse effects.
Calcium channel blockers might reduce lithium concentrations. Monitor lithium levels with concurrent use. Calcium channel blockers might also increase the adverse neurological and gastrointestinal adverse effects of lithium. It is unclear if these interactions would occur with the smaller doses found in lithium supplements.

Likelihood Possible Evidence D
Methyldopa (Aldomet)

Theoretically, taking lithium supplements with methyldopa might increase the risk of lithium toxicity.
Concurrent use of methyldopa with lithium increases the risk of lithium toxicity. It is unclear if this interaction would be clinically significant with the smaller doses found in lithium supplements.

Likelihood Probable Evidence D
Methylxanthines

Theoretically, taking lithium supplements with methylxanthines might decrease lithium levels.
Xanthines such as aminophylline, caffeine, and theophylline (Theo-Dur, Theo-24, others) might increase the clearance of lithium. It is unclear if this interaction would be clinically significant with the smaller doses found in lithium supplements.

Likelihood Probable Evidence D
Nonsteroidal Anti-Inflammatory Drugs (Nsaids)

Theoretically, taking lithium supplements with NSAIDs might increase lithium levels and adverse effects.
NSAIDs can decrease the renal clearance of lithium and increase lithium levels. It is unclear if this interaction would be clinically significant with the smaller doses found in lithium supplements.

Likelihood Probable Evidence D
Phenothiazines

Theoretically, taking lithium supplements with phenothiazines might decrease the levels and clinical effects of phenothiazines.
Concomitant use of lithium with phenothiazines might reduce lithium concentrations. Lithium might also reduce phenothiazine concentrations, making the pharmacokinetic effect unpredictable. It is unclear if these interactions would occur with the smaller doses found in lithium supplements.

Likelihood Probable Evidence D
Skeletal Muscle Relaxants

Theoretically, taking lithium supplements with skeletal muscle relaxants might prolong neuromuscular blockade.
Lithium might prolong neuromuscular blockade. It is unclear if this interaction would occur with the smaller doses found in lithium supplements.

Likelihood Probable Evidence D
Lithium full monograph & interactions

GABA2 drug types · 419 drugs

Antihypertensive Drugs

Theoretically, taking GABA with antihypertensive drugs might increase the risk of hypotension.
Some clinical research shows that GABA can decrease blood pressure in patients with hypertension.

Likelihood Possible Evidence B
Cns Depressants

Theoretically, GABA might have additive sedative effects when used in conjunction with CNS depressants. However, it is unclear if this concern is clinically relevant.
Endogenous GABA has well-established relaxant effects and GABA(A) receptors have an established physiological role in sleep. However, the effects of GABA supplements are unclear, as it is unknown whether exogenous GABA crosses the blood-brain barrier. Although there have been limited reports of drowsiness or tiredness with GABA supplements, these effects have not been widely reported in clinical studies. Additionally, intravenous GABA 0.1-1 mg/kg has been shown to induce anxiety in a dose-dependent manner.

Likelihood Unlikely Evidence D
GABA full monograph & interactions

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

5-HTP3 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
5-HTP full monograph & interactions

Taurine2 drug types · 173 drugs

Antihypertensive Drugs

Theoretically, taurine might increase the risk of hypotension when taken with antihypertensive drugs.
Some clinical evidence suggests that taurine can reduce both systolic and diastolic blood pressure.

Likelihood Probable Evidence D
Lithium

Theoretically, taurine might reduce excretion and increase plasma levels of lithium.
Taurine is thought to have diuretic properties, which might reduce the excretion of lithium.

Likelihood Probable Evidence D
Taurine full monograph & interactions

L-Cysteine Dihydrochloride1 drug type · 86 drugs

Antidiabetes Drugs

Theoretically, taking L-cysteine supplements with antidiabetes drugs might increase the risk of hypoglycemia.
Animal research suggests that L-cysteine can have hypoglycemic effects.

Likelihood Possible Evidence D
L-Cysteine Dihydrochloride 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

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
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 Amino Acid Neurotransmitter Formula, from the product label.

Allergy Research Group

See all Allergy Research Group products
Name
Allergy Research Group
City
Alameda
State
CA
ZipCode
94502
Phone Number
510-263-2000
Web Address
www.allergyresearchgroup.com
Pharmacist Counseling Corner

Amino Acid Neurotransmitter Formula by Allergy Research Group: Common Questions

Does Amino Acid Neurotransmitter Formula by Allergy Research Group interact with any medications?
Yes. Based on its ingredients, Amino Acid Neurotransmitter Formula has a known interaction with 912 medications, including 267 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Amino Acid Neurotransmitter Formula contains 21 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.
What are these amino acids supposed to do?
Amino acids are building blocks your body uses to make proteins and neurotransmitters — chemical messengers in your brain and nervous system. This formula includes 15 different amino acids plus taurine, 5-HTP, L-theanine, GABA, and lithium to support brain and nervous system function. Different amino acids have different roles: some support mood, others support memory, and some support muscle and immune health.
Is this safe if I take blood pressure medication?
No — not automatically. L-arginine, L-theanine, GABA, and taurine all interact with blood pressure drugs and can lower your blood pressure further, raising the risk of dizziness or fainting. You need to talk to your pharmacist before adding this product, especially if you also take ACE inhibitors or ARBs.
Can I take this if I'm on an antidepressant?
It depends on which one. 5-HTP in this formula interacts with many antidepressants and raises the risk of serotonin syndrome (a serious condition with agitation, rapid heart rate, and confusion). Lithium also carries risks with antidepressants. Check with your pharmacist before starting — don't add it on your own.
Is it safe during pregnancy?
No — not across the board. L-phenylalanine is unsafe during pregnancy, and L-serine and 5-HTP should be avoided due to insufficient safety data. Several other amino acids (L-tyrosine, L-lysine) haven't been well studied in pregnancy either. Talk to your doctor before taking this if you're pregnant or planning to become pregnant.
What are the most common side effects?
The amino acids in this formula can cause gastrointestinal upset — bloating, nausea, diarrhea, constipation — especially at higher doses. 5-HTP commonly causes drowsiness, headache, and nausea. Some people report headache or dizziness with L-theanine or L-tyrosine. If your stomach gets upset, you can try taking it with food and starting with a smaller dose.
Can I take this with Parkinson's medication (levodopa)?
No — L-phenylalanine and L-tyrosine in this formula compete with levodopa for absorption into the brain and can reduce how well it works, worsening tremor and rigidity. Avoid this product if you take levodopa, or talk to your doctor about whether a different supplement might work better for you.

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

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Amino Acid Neurotransmitter Formula label
Go deeper

The Full Monographs Behind Amino Acid Neurotransmitter Formula’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

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

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

Alpha-alanine

Alpha-alanine (usually called alanine) is a non-essential amino acid your body can make on its own and that you also get from protein foods. Most people do not need a supplement, and strong...

Read the full Alpha-alanine 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

Histidine

Histidine is an essential amino acid your body needs to build proteins and to make compounds like histamine and carnosine. Most people get enough from a normal diet, and good-quality researc...

Read the full Histidine 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 → Herb & supplement monograph

Serine

Serine is an amino acid your body can make on its own and also gets from protein-rich foods, so most people do not need a supplement. L-serine has been studied for certain neurological condi...

Read the full Serine monograph → Herb & supplement monograph

Taurine

Interacts with 173 drugs

Taurine is an amino acid your body makes naturally and that you also get from animal foods. It is widely used in energy drinks and sports supplements, and short-term use appears generally sa...

Read the full Taurine monograph → Herb & supplement monograph

5-htp

Interacts with 398 drugs

5-HTP is a compound your body uses to make serotonin, and people take it as a supplement hoping to improve mood, sleep, and headaches. Some early research is promising, but the overall evide...

Read the full 5-htp monograph → Herb & supplement monograph

Theanine

Interacts with 565 drugs

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong drowsiness. Early research suggests it may...

Read the full Theanine monograph → Herb & supplement monograph

Gamma-aminobutyric Acid (gaba)

Interacts with 419 drugs

GABA is a calming chemical messenger (neurotransmitter) that your body makes on its own, and it is sold as a supplement for stress, anxiety, and sleep. The science behind oral GABA supplemen...

Read the full Gamma-aminobutyric Acid (gaba) monograph → Herb & supplement monograph

L-cysteine

Interacts with 86 drugs

L-cysteine is a sulfur-containing amino acid your body uses to make proteins and the antioxidant glutathione. Most people get enough from food, and supplements are usually well tolerated, bu...

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

Lithium

Interacts with 515 drugs

Lithium is a naturally occurring metal that, in prescription form (lithium carbonate or citrate), is an FDA-approved, well-proven treatment for bipolar disorder. Low-dose supplement forms li...

Read the full Lithium monograph →
Sources

Sources & How We Checked

Amino Acid Neurotransmitter Formula'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 239 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 →

Glycine 5 references
  1. Heresco-Levy U, Javitt DC, Ermilov M, et al. Efficacy of high-dose glycine in the treatment of enduring negative symptoms of schizophrenia. Arch Gen Psychiatry 1999;56:29-36.. PubMed
  2. Potkin SG, Jin Y, Bunney BG, Costa J, Gulasekaram B. Effect of clozapine and adjunctive high-dose glycine in treatment-resistant schizophrenia. Am J Psychiatry 1999;156:145-7.. PubMed
  3. Gusev EI, Skvortsova VI, Dambinova SA, et al. Neuroprotective effects of glycine for therapy of acute ischaemic stroke. Cerebrovasc Dis 2000;10:49-60. PubMed
  4. Inagawa K, Kawai N, Ono K, Sukegawa E, Tsubuku S, Takahashi M. Assessment of acute adverse effects of glycine ingestion at a high dose in human volunteers. Seikatsu Eisei. 2006; 50:27-32.
  5. Woods SW, Walsh BC, Hawkins KA, Miller TJ, Saksa JR, D'Souza DC, Pearlson GD, Javitt DC, McGlashan TH, Krystal JH. Glycine treatment of the risk syndrome for psychosis: report of two pilot studies. Eur Neuropsychopharmacol. 2013 Aug;23(8):931-40. PubMed

See these in context on the Glycine 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.
  2. Clarkson P, Adams MR, Powe AJ, et al. Oral L-arginine improves endothelium-dependent dilation in hypercholesterolemic young adults. J Clin Invest 1996;97:1989-94. PubMed
  3. Tenenbaum A, Fisman EZ, Motro M. L-arginine: Rediscovery in progress. Cardiology 1998;90:153-9.
  4. Brittenden J, Park KGM, Heys SD, et al. L-Arginine stimulates host defenses in patients with breast cancer. Surgery 1994;115:205-12.
  5. Korting GE, Smith SD, Wheeler MA, et al. A randomized double-blind trial of oral L-arginine for treatment of interstitial cystitis. J Urol 1999;161:558-65. DOI
  6. Rector TS, Bank AJ, Mullen KA, et al. Randomized, double-blind, placebo-controlled study of supplemental oral L-arginine in patients with heart failure. Circulation 1996;93:2135-41.
  7. Siani A, Pagano E, Iacone R, et al. Blood pressure and metabolic changes during dietary L-arginine supplementation in humans. Am J Hypertens 2000;13:547-51. PubMed
  8. Cheng JW, Balwin SN. L-arginine in the management of cardiovascular diseases. Ann Pharmacother 2001;35:755-64. PubMed
  9. Wallace AW, Tom WL. Interaction of L-arginine and phosphodiesterase inhibitors in vasodilation of the porcine internal mammary artery. Anesth Analg 2000;90:840-6. DOI
  10. Huynh NT, Tayek JA. Oral arginine reduces systemic blood pressure in type 2 diabetes: its potential role in nitric oxide generation. J Am Coll Nutr 2002;21:422-7.. PubMed
  11. Staff AC, Berge L, Haugen G, et al. Dietary supplementation with L-arginine or placebo in women with pre-eclampsia. Acta Obstet Gynecol Scand 2004;83:103-7.
  12. Resnick DJ, Softness B, Murphy AR, et al. Case report of an anaphylactoid reaction to arginine. Ann Allergy Asthma Immunol 2002;88:67-8. PubMed
  13. Anon. Arginine hydrochloride injection (marketed as R-Gene 10). FDA Drug Safety Newsletter 2009;2(2):16-18. Available at: www.fda.gov/Drugs/DrugSafety/DrugSafetyNewsletter/default.htm.
  14. Higashi Y, Oshima T, Sasaki S, et. al. Angiotensin-converting enzyme inhibition, but not calcium antagonism, improves a response of the renal vasculature to L-arginine in patients with essential hypertension. Hypertension. 1998 Jul;32(1):16-24.
  15. Facchinetti, F., Longo, M., Piccinini, F., Neri, I., and Volpe, A. L-arginine infusion reduces blood pressure in preeclamptic women through nitric oxide release. J Soc Gynecol.Investig. 1999;6(4):202-207. DOI
  16. de Gouw, H. W., Verbruggen, M. B., Twiss, I. M., and Sterk, P. J. Effect of oral L-arginine on airway hyperresponsiveness to histamine in asthma. Thorax 1999;54(11):1033-1035. PubMed
  17. Komers, R., Komersova, K., Kazdova, L., Ruzickova, J., and Pelikanova, T. Effect of ACE inhibition and angiotensin AT1 receptor blockade on renal and blood pressure response to L-arginine in humans. J Hypertens. 2000;18(1):51-59. PubMed
  18. Cartledge, J. J., Davies, A. M., and Eardley, I. A randomized double-blind placebo-controlled crossover trial of the efficacy of L-arginine in the treatment of interstitial cystitis. BJU.Int. 2000;85(4):421-426.
  19. Sozykin, A. V., Noeva, E. A., Balakhonova, T. V., Pogorelova, O. A., and Men'shikov, M. I. [Effect of L-arginine on platelet aggregation, endothelial function adn exercise tolerance in patients with stable angina pectoris]. Ter.Arkh. 2000;72(8):24-27.
  20. Nagaya, N., Uematsu, M., Oya, H., Sato, N., Sakamaki, F., Kyotani, S., Ueno, K., Nakanishi, N., Yamagishi, M., and Miyatake, K. Short-term oral administration of L-arginine improves hemodynamics and exercise capacity in patients with precapillary pulmona
  21. Stokes, G. S., Barin, E. S., Gilfillan, K. L., and Kaesemeyer, W. H. Interactions of L-arginine, isosorbide mononitrate, and angiotensin II inhibitors on arterial pulse wave. Am J Hypertens. 2003;16(9 Pt 1):719-724.
  22. Park, K. G., Heys, S. D., Blessing, K., Kelly, P., McNurlan, M. A., Eremin, O., and Garlick, P. J. Stimulation of human breast cancers by dietary L-arginine. Clin.Sci.(Lond) 1992;82(4):413-417.
  23. Palloshi, A., Fragasso, G., Piatti, P., Monti, L. D., Setola, E., Valsecchi, G., Galluccio, E., Chierchia, S. L., and Margonato, A. Effect of oral L-arginine on blood pressure and symptoms and endothelial function in patients with systemic hypertension,
  24. Schlaich, M. P., Ahlers, B. A., Parnell, M. M., and Kaye, D. M. beta-Adrenoceptor-mediated, nitric-oxide-dependent vasodilatation is abnormal in early hypertension: restoration by L-arginine. J Hypertens. 2004;22(10):1917-1925. PubMed
  25. Neri, I., Blasi, I., and Facchinetti, F. Effects of acute L-arginine infusion on non-stress test in hypertensive pregnant women. J Matern.Fetal Neonatal Med. 2004;16(1):23-26. PubMed
  26. Rytlewski, K., Olszanecki, R., Korbut, R., and Zdebski, Z. Effects of prolonged oral supplementation with l-arginine on blood pressure and nitric oxide synthesis in preeclampsia. Eur.J Clin.Invest 2005;35(1):32-37.
  27. Mansoor, J. K., Morrissey, B. M., Walby, W. F., Yoneda, K. Y., Juarez, M., Kajekar, R., Severinghaus, J. W., Eldridge, M. W., and Schelegle, E. S. L-arginine supplementation enhances exhaled NO, breath condensate VEGF, and headache at 4,342 m. High Alt.M
  28. Neri, I., Jasonni, V. M., Gori, G. F., Blasi, I., and Facchinetti, F. Effect of L-arginine on blood pressure in pregnancy-induced hypertension: a randomized placebo-controlled trial. J Matern.Fetal Neonatal Med. 2006;19(5):277-281.
  29. Lucotti, P., Setola, E., Monti, L. D., Galluccio, E., Costa, S., Sandoli, E. P., Fermo, I., Rabaiotti, G., Gatti, R., and Piatti, P. Beneficial effects of a long-term oral L-arginine treatment added to a hypocaloric diet and exercise training program in
  30. Savoye, G., Jemaa, Y., Mosni, G., Savoye-Collet, C., Morcamp, P., Dechelotte, P., Bouin, M., Denis, P., and Ducrotte, P. Effects of intragastric L-arginine administration on proximal stomach tone under basal conditions and after an intragastric diet. Dig PubMed
  31. Facchinetti, F., Saade, G. R., Neri, I., Pizzi, C., Longo, M., and Volpe, A. L-arginine supplementation in patients with gestational hypertension: a pilot study. Hypertens.Pregnancy. 2007;26(1):121-130. PubMed
  32. Jovanovic, A., Gerrard, J., and Taylor, R. The second-meal phenomenon in type 2 diabetes. Diabetes Care 2009;32(7):1199-1201. PubMed
  33. Fontanive P, Saponati G, Iurato A, et al. Effects of L-arginine on the Minnesota Living with Heart Failure Questionnaire quality-of-life score in patients with chronic systolic heart failure. Med.Sci.Monit. 2009;15:CR606-11.
  34. Doutreleau, S., Rouyer, O., Di, Marco P., Lonsdorfer, E., Richard, R., Piquard, F., and Geny, B. L-arginine supplementation improves exercise capacity after a heart transplant. Am J Clin.Nutr. 2010;91(5):1261-1267. PubMed
  35. Ast, J., Jablecka, A., Bogdanski, P., Smolarek, I., Krauss, H., and Chmara, E. Evaluation of the antihypertensive effect of L-arginine supplementation in patients with mild hypertension assessed with ambulatory blood pressure monitoring. Med.Sci.Monit. 2
  36. Saleh, A. I., Abdel Maksoud, S. M., El-Maraghy, S. A., and Gad, M. Z. Protective effect of L-arginine in experimentally induced myocardial ischemia: comparison with aspirin. J Cardiovasc.Pharmacol.Ther 2011;16(1):53-62. PubMed
  37. Dong, J. Y., Qin, L. Q., Zhang, Z., Zhao, Y., Wang, J., Arigoni, F., and Zhang, W. Effect of oral L-arginine supplementation on blood pressure: a meta-analysis of randomized, double-blind, placebo-controlled trials. Am.Heart J 2011;162(6):959-965. PubMed
  38. Hertz, P. and Richardson, J. A. Arginine-induced hyperkalemia in renal failure patients. Arch.Intern.Med. 1972;130(5):778-780. DOI
  39. Bushinsky, D. A. and Gennari, F. J. Life-threatening hyperkalemia induced by arginine. Ann.Intern.Med. 1978;89(5 Pt 1):632-634. PubMed
  40. Adams, M. R., Forsyth, C. J., Jessup, W., Robinson, J., and Celermajer, D. S. Oral L-arginine inhibits platelet aggregation but does not enhance endothelium-dependent dilation in healthy young men. J Am Coll.Cardiol 1995;26(4):1054-1061. PubMed
  41. Dell'Omo, G., Catapano, G., Ebel, M., Gazzano, A., Ducci, M., Del, Chicca M., Clerico, A., and Pedrinelli, R. [Pressor, renal and endocrine effects of systemic infusion of L-arginine in hypertensive patients]. Ann.Ital Med.Int. 1995;10(2):107-112.
  42. Higashi, Y., Oshima, T., Ozono, R., Watanabe, M., Matsuura, H., and Kajiyama, G. Effects of L-arginine infusion on renal hemodynamics in patients with mild essential hypertension. Hypertension 1995;25(4 Pt 2):898-902.
  43. Bode-Boger, S. M., Boger, R. H., Creutzig, A., Tsikas, D., Gutzki, F. M., Alexander, K., and Frolich, J. C. L-arginine infusion decreases peripheral arterial resistance and inhibits platelet aggregation in healthy subjects. Clin.Sci.(Lond) 1994;87(3):303
  44. Marfella, R., Acampora, R., Verrazzo, G., Ziccardi, P., De, Rosa N., Giunta, R., and Giugliano, D. Metformin improves hemodynamic and rheological responses to L-arginine in NIDDM patients. Diabetes Care 1996;19(9):934-939. PubMed
  45. Giugliano, D., Marfella, R., Verrazzo, G., Acampora, R., Coppola, L., Cozzolino, D., and D'Onofrio, F. The vascular effects of L-Arginine in humans. The role of endogenous insulin. J Clin.Invest 2-1-1997;99(3):433-438. PubMed
  46. Khan, F., Litchfield, S. J., McLaren, M., Veale, D. J., Littleford, R. C., and Belch, J. J. Oral L-arginine supplementation and cutaneous vascular responses in patients with primary Raynaud's phenomenon. Arthritis Rheum. 1997;40(2):352-357.
  47. Wolf, A., Zalpour, C., Theilmeier, G., Wang, B. Y., Ma, A., Anderson, B., Tsao, P. S., and Cooke, J. P. Dietary L-arginine supplementation normalizes platelet aggregation in hypercholesterolemic humans. J Am Coll.Cardiol 3-1-1997;29(3):479-485. PubMed
  48. Schellong, S. M., Boger, R. H., Burchert, W., Bode-Boger, S. M., Galland, A., Frolich, J. C., Hundeshagen, H., and Alexander, K. Dose-related effect of intravenous L-arginine on muscular blood flow of the calf in patients with peripheral vascular disease
  49. Marietta, M., Facchinetti, F., Neri, I., Piccinini, F., Volpe, A., and Torelli, G. L-arginine infusion decreases platelet aggregation through an intraplatelet nitric oxide release. Thromb.Res 10-15-1997;88(2):229-235. PubMed
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  51. Vadillo-Ortega F, Perichart-Perera O, Espino S, et al. Effect of supplementation during pregnancy with L-arginine and antioxidant vitamins in medical food on pre-eclampsia in high risk population: randomised controlled trial. BMJ. 2011 May 19;342:d2901. PubMed
  52. Camarena Pulido EE, García Benavides L, Panduro Barón JG, et al. Efficacy of L-arginine for preventing preeclampsia in high-risk pregnancies: A double-blind, randomized, clinical trial. Hypertens Pregnancy. 2016;35(2):217-25. PubMed
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  54. Binet Q, Dufour I, Agneessens E, et al. The second case of a young man with L-arginine-induced acute pancreatitis. Clin J Gastroenterol. 2018;11(5):424-427. PubMed
  55. El Taieb M, Hegazy E, Ibrahim A. Daily oral l-arginine plus tadalafil in diabetic patients with erectile dysfunction: A double-blinded, randomized, controlled clinical trial. J Sex Med. 2019;16(9):1390-1397.
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Alpha-alanine 2 references
  1. Amino acids — MedlinePlus (NIH) Source
  2. Dietary Supplements: What You Need to Know — NIH Office of Dietary Supplements Source

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Methionine 12 references
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Tyrosine 4 references
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Phenylalanine 23 references
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Histidine 3 references
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Threonine 4 references
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Lysine 7 references
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Serine 3 references
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Taurine 21 references
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5-htp 32 references
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Theanine 6 references
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Gamma-aminobutyric Acid (gaba) 12 references
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See these in context on the Gamma-aminobutyric Acid (gaba) monograph →

L-cysteine 2 references
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See these in context on the L-cysteine monograph →

Lithium 26 references
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See these in context on the Lithium monograph →

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

© 2021 Therapeutic Research Center, LLC

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