Major interaction on record — check this product against your medications before combining. Based on 5 of 6 ingredients. Check your meds →
Dietary supplement

NeuroAmino-SP (K-44) Ingredients & Drug Interactions

by Apex Energetics

NeuroAmino-SP (K-44) 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 NeuroAmino-SP (K-44) 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

NeuroAmino-SP (K-44) is a dietary supplement by Apex Energetics with 6 active ingredients. Its ingredients are commonly taken for mental focus and alertness, coping with stress, fatigue and sleep loss.Based on those ingredients, 427 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are 5-HTP, L-Tryptophan, 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 NeuroAmino-SP (K-44) by Apex Energetics

Ask about any prescription or over-the-counter medication and we check it for interactions with NeuroAmino-SP (K-44) by Apex Energetics — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of NeuroAmino-SP (K-44) by Apex Energetics

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

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 27, 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 6 of its 6 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

NeuroAmino-SP contains 6 active ingredients: L-tyrosine, L-phenylalanine, L-tryptophan, N-acetyl L-tyrosine, 5-HTP, and alpha-GPC. These are amino acids and amino acid derivatives meant to support brain chemistry and cognitive function.

L-tyrosine and L-phenylalanine are precursors to neurotransmitters like dopamine and norepinephrine; L-tryptophan is a precursor to serotonin; 5-HTP also raises serotonin; and alpha-GPC is a choline compound believed to support memory and brain health. The capsules also contain vegetarian capsule material and cellulose as inactive ingredients.

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: mood, sleep, and stress support.
  • We looked for evidence on: Anxiety, Depression, Insomnia, Stress, Migraine headache, Fibromyalgia — and 4 related terms.
  • The strongest evidence on file: 5-htp is rated "Possibly Effective" for Depression (Natural Medicines).
  • Also on file: Tyrosine is rated "Possibly Effective" for Cognitive function, Memory.
  • Also on file: L-tryptophan is rated "Possibly Ineffective" for Depression.

The evidence for these ingredients is mixed. L-tyrosine is effective for phenylketonuria (PKU) and possibly effective for cognitive function and memory, though not likely to boost athletic performance.

L-phenylalanine is possibly effective for vitiligo but possibly ineffective for ADHD. L-tryptophan is possibly ineffective for depression.

5-HTP is possibly effective for depression. Alpha-GPC is possibly effective for Alzheimer disease.

For several other uses listed—including anxiety, alcohol use disorder, dementia, ADHD, and panic disorder—the evidence isn't established in our data.

The evidence, ingredient by ingredient Tyrosine Phenylalanine L-tryptophan 5-htp Alpha-gpc

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 5 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

L-tyrosine, L-phenylalanine, L-tryptophan, 5-HTP, and alpha-GPC are generally well tolerated when used short-term at standard doses, though side effects are common. The most frequent complaints include headache, nausea, heartburn, diarrhea, and drowsiness.

L-tryptophan carries historical concern: a contaminated batch from one Japanese manufacturer in 1989 caused a rare neurological disorder (eosinophilia-myalgia syndrome, or EMS) in over 1,500 people; modern products are not known to carry that risk. Regarding pregnancy and breastfeeding: L-phenylalanine and L-tryptophan should be avoided during pregnancy due to insufficient safety data, and both should be avoided while breastfeeding.

5-HTP and alpha-GPC also lack enough safety information and should be avoided in pregnancy and lactation unless a doctor directs otherwise. L-tyrosine and N-acetyl L-tyrosine do not have pregnancy or breastfeeding safety data on file.

Side effects, ingredient by ingredient Tyrosine Phenylalanine L-tryptophan 5-htp Alpha-gpc

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?
  • 5 of the 5 matched ingredients can interact with medications — L-tryptophan, Phenylalanine, 5-htp, Tyrosine, Alpha-gpc.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: Parkinson's medications.
  • For scale: 427 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 NeuroAmino-SP, double-check with your doctor or pharmacist if you're on levodopa (a Parkinson drug), because L-phenylalanine and L-tyrosine can reduce its effectiveness. If you take an MAOI antidepressant, ask your pharmacist—L-phenylalanine raises the risk of a dangerous blood pressure spike.

Anyone on serotonergic medications (certain antidepressants like SSRIs, SNRIs, or migraine drugs) should confirm it's safe, since L-tryptophan and 5-HTP can increase serotonin effects. Also check if you're on CNS depressants (sedatives, sleep aids, pain relievers with sedating properties), because L-tryptophan and 5-HTP can add to drowsiness.

If you take baclofen (a muscle relaxant) or the motion-sickness patch (scopolamine), mention this product to your pharmacist as well.

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.

NeuroAmino-SP is a multi-ingredient brain-support formula best suited for people without Parkinson disease, those not on MAOIs or serotonergic medications, and those not pregnant or breastfeeding. If you take any prescription medications—especially levodopa, any MAOI, an antidepressant, sleep aids, or any other brain or mood medication—check with your doctor or pharmacist before starting this product, as the interaction risk is real.

The side effects (nausea, headache, drowsiness) are generally mild, but long-term safety data for some ingredients is limited.

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

Assessment coverage: 5 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Sep 24, 2019.

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

At a glance

General information

Key facts about NeuroAmino-SP (K-44), straight from the product label.

Brand Apex Energetics
Net contents 90 Capsule(s)
Market status On market
Date entered into DSLD Sep 24, 2019
DSLD ID 206621
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 NeuroAmino-SP (K-44) by Apex Energetics, 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 Vegetarian Capsule(s)
Maximum serving Sizes:
1 Vegetarian Capsule(s)
Servings per container
90
IngredientAmount% DV
L-Tyrosine100 mg--
L-Phenylalanine200 mg--
L-Tryptophan40 mg--
N-Acetyl L-Tyrosine100 mg--
5-HTP40 mg--
Alpha-GPC100 mg--

Other ingredients: Vegetarian Capsule, Cellulose

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
General Statements

Nutritional complexes

FDA Statement of Identity

Amino Acid & Herbal Dietary Supplement

Suggested/Recommended/Usage/Directions

Suggested Use: Take 1 capsule 3 times a day, or as directed by your healthcare professional.

Storage

Storage instructions: Store at room temperature away from direct sunlight. Keep this bottle tightly closed.

Formula

Warning: This product contains 5-HTP.

Precautions

Warning: This product contains 5-HTP.

Consult your healthcare professional before use if pregnant, nursing, taking antidepressants or other medications, or for any use by minors.

Consult your healthcare professional before use if pregnant, nursing, taking antidepressants or other medications, or for any use by minors.

Do not use if safety seal is broken or missing.

Keep out of reach of children.

For nutritional use only.

FDA Disclaimer Statement

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

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

See for yourself

NeuroAmino-SP (K-44) by Apex Energetics label

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

NeuroAmino-SP (K-44) 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 NeuroAmino-SP (K-44) by Apex Energetics

These are the 6 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Vegetarian Capsule(s) Dosage formCapsule Servings per container90 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-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-Tryptophan

Interacts with
394 drugs
40 mg per serving

L-tryptophan is an essential amino acid the body uses to make serotonin and melatonin, and people take it to support sleep and mood. The evidence for...

L-Tryptophan monograph & interactions

N-Acetyl L-Tyrosine

100 mg per serving

5-HTP

Interacts with
398 drugs
40 mg per serving Form: Griffonia simplicifolia

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

Alpha-GPC

Interacts with
16 drugs
100 mg per serving

Alpha-GPC is a choline-containing compound used mainly for memory, brain health, and as a choline source. There is some evidence it may help cognition...

Alpha-GPC monograph & interactions

Other (inactive) ingredients: Vegetarian Capsule, Cellulose. These complete the product’s ingredient list but are not active constituents.

Interaction report

NeuroAmino-SP (K-44) by Apex Energetics Drug Interactions

Want to check YOUR meds against NeuroAmino-SP (K-44)?

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
427Drugs
253 Major 168 Moderate 6 Minor

Ingredients driving the most interactions

5-HTP 398
L-Tryptophan 394
L-Tyrosine 21
L-Phenylalanine 16
Alpha-GPC 16

Individual Drug Interactions

The ingredients in NeuroAmino-SP (K-44) interact with 427 drugs. Click any drug to see the details.

5 of the 6 ingredients in NeuroAmino-SP (K-44) interact with drugs. Each result below shows which ingredient is responsible. 5-HTP L-Tryptophan L-Tyrosine L-Phenylalanine Alpha-GPC

Each ingredient & the kinds of drugs it affects

For each ingredient in NeuroAmino-SP (K-44) 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.

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

L-Tryptophan2 drug types · 394 drugs

Cns Depressants

Theoretically, concomitant use of L-tryptophan with CNS depressants might cause additive sedative effects.
Clinical research shows that L-tryptophan can cause fatigue and drowsiness.

Likelihood Probable Evidence B
Serotonergic Drugs

Theoretically, combining L-tryptophan with serotonergic drugs might cause additive serotonergic effects.
L-tryptophan is a precursor to serotonin. Theoretically, combining serotonergic drugs with L-tryptophan might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders.

Likelihood Possible Evidence D
L-Tryptophan 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

Alpha-GPC1 drug type · 16 drugs

Scopolamine (Transderm Scop)

Theoretically, alpha-GPC might decrease the effects of scopolamine.
A small clinical study shows that alpha-GPC can partially counteract the attention and memory impairment effects caused by scopolamine given intramuscularly. Whether alpha-GPC can decrease the beneficial anti-motion sickness effects of the scopolamine patch (Transderm Scop) is unclear.

Likelihood Possible Evidence B
Alpha-GPC full monograph & interactions
The maker

Brand information

Manufacturer and brand details for NeuroAmino-SP (K-44), from the product label.

Apex Energetics

See all Apex Energetics products
Name
Apex Energetics, Inc.
Street Address
16592 Hale Ave.
City
Irvine
State
CA
ZipCode
92606
Pharmacist Counseling Corner

NeuroAmino-SP (K-44) by Apex Energetics: Common Questions

Does NeuroAmino-SP (K-44) by Apex Energetics interact with any medications?
Yes. Based on its ingredients, NeuroAmino-SP (K-44) has a known interaction with 427 medications, including 253 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
NeuroAmino-SP (K-44) contains 6 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.
Is it safe to take this while I'm pregnant?
No. L-phenylalanine and L-tryptophan should be avoided during pregnancy because safety hasn't been established. 5-HTP and alpha-GPC also lack enough pregnancy safety data and should be avoided unless a doctor tells you otherwise. Talk with your doctor or pharmacist before taking this product if you're pregnant or planning to become pregnant.
Can I take this if I'm breastfeeding?
The safety data advises against it. L-phenylalanine, L-tryptophan, 5-HTP, and alpha-GPC all lack sufficient safety information for breastfeeding, and the safety notes recommend avoiding them. Check with your doctor or pharmacist for personalized guidance.
What are the most common side effects I might notice?
Headache, nausea, heartburn, drowsiness, diarrhea, and fatigue are the most frequently reported. These tend to be mild and may depend on dose. If you experience severe gastrointestinal distress, unusual mood changes, or hallucinations, stop and contact your healthcare provider.
Does this really help with memory and brain function?
The evidence is limited. L-tyrosine is possibly effective for memory and cognitive function, and alpha-GPC is possibly effective for Alzheimer disease. L-tryptophan is possibly ineffective for depression. For most other uses—anxiety, dementia, ADHD, panic disorder—the evidence in our data isn't established, so results vary by person.
Can I take this with my antidepressant?
It depends on which antidepressant you're on. L-tryptophan and 5-HTP both raise serotonin, and combining them with serotonergic antidepressants (SSRIs, SNRIs, others) can theoretically cause serotonin syndrome, a serious condition. Ask your doctor or pharmacist to check your specific medication before you start.
I've heard L-tryptophan was recalled. Is this product safe?
The 1989 contamination that caused a rare neurological disorder (EMS) came from a single Japanese manufacturer and no longer affects modern products. That said, L-tryptophan is generally well tolerated today, though the safety notes remind you to use it carefully and under professional guidance.

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

Not sure if NeuroAmino-SP (K-44) is safe with your meds?

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

NeuroAmino-SP (K-44) label
Go deeper

The Full Monographs Behind NeuroAmino-SP (K-44)’s Ingredients

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

Herb & supplement monograph

Tyrosine

Interacts with 21 drugs

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

Read the full Tyrosine monograph → 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

L-tryptophan

Interacts with 394 drugs

L-tryptophan is an essential amino acid the body uses to make serotonin and melatonin, and people take it to support sleep and mood. The evidence for supplement use is limited and mixed, and...

Read the full L-tryptophan 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

Alpha-gpc

Interacts with 16 drugs

Alpha-GPC is a choline-containing compound used mainly for memory, brain health, and as a choline source. There is some evidence it may help cognition in people with dementia, but evidence i...

Read the full Alpha-gpc monograph →
Sources

Sources & How We Checked

NeuroAmino-SP (K-44)'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 81 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

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

See these in context on the Tyrosine monograph →

Phenylalanine 23 references
  1. Rouse B, Azen C, Koch R, et al. Maternal phenylketonuria collaborative Study (MPKUCS) offspring: facial anomalies, malformations, and early neurological sequelae. Am J Med Genet 1997;69:89-95. DOI
  2. Sturtevant FM. Use of aspartame in pregnancy. Int J Fertil 1985;30:85-7.
  3. Silkaitis RP, Mosnaim AD. Pathways linking L-phenylalanine and 2-phenylethylamine with p-tyramine in rabbit brain. Brain Res 1976;114:105-15.
  4. Lehmann WD, Theobald N, Fischer R, Heinrich HC. Stereospecificity of phenylalanine plasma kinetics and hydroxylation in man following oral application of a stable isotope-labelled pseudo-racemic mixture of L- and D-phenylalanine. Clin Chim Acta 1983;128 PubMed
  5. Mosnik DM, Spring B, Rogers K, Baruah S. Tardive dyskinesia exacerbated after ingestion of phenylalanine by schizophrenic patients. Neuropsychopharmacology 1997;16:136-46. PubMed
  6. Siddiqui AH, Stolk LM, Bhaggoe R, et al. L-phenylalanine and UVA irradiation in the treatment of vitiligo. Dermatology 1994;88:215-8. PubMed
  7. Birkmayer W, Riederer P, Linauer W, Knoll J. L-deprenyl plus L-phenylalanine in the treatment of depression. J Neural Transm 1984;59:81-7. PubMed
  8. Nutt JG, Woodward WR, Hammerstad JP, et al. The "on-off" phenomenon in Parkinson's disease. Relation to levodopa absorption and transport. N Engl J Med 1984;310:483-8. PubMed
  9. Baruzzi A, Contin M, Riva R, et al. Influence of meal ingestion time on pharmacokinetics of orally administered levodopa in parkinsonian patients. Clin Neuropharmacol 1987;10:527-37. PubMed
  10. Juncos JL, Fabbrini G, Mouradian MM, et al. Dietary influences on the antiparkinsonian response to levodopa. Arch Neurol 1987;44:1003-5. PubMed
  11. Eriksson T, Granerus AK, Linde A, et al. "On-off" phenomenon in Parkinson's disease: relationship between dopa and other large neutral amino acids in plasma. Neurology 1988;38:1245-8. PubMed
  12. Baker GB, Bornstein RA, Rouget AC, et al. Phenylethylaminergic mechanisms in attention-deficit disorder. Biol Psychiatry 1991;29:15-22.. PubMed
  13. Wood DR, Reimherr FW, Wender PH. Treatment of attention deficit disorder with DL-phenylalanine. Psychiatry Res 1985;16:21-6.. PubMed
  14. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (Macronutrients). Washington, DC: National Academy Press, 2002. Available at: http://www.n
  15. Cederbaum S. Phenylketonuria: an update. Curr Opin Pediatr 2002;14:702-6. PubMed
  16. Cejudo-Ferragud, E., Nacher, A., Polache, A., Cercos-Fortea, T., Merino, M., and Casabo, V. G. Evidence of competitive inhibition for the intestinal absorption of baclofen by phenylalanine. Int J of Pharm (Amsterdam) 1996;132:63-69. DOI
  17. Fischer, E., Heller, B., Nachon, M., and Spatz, H. Therapy of depression by phenylalanine. Preliminary note. Arzneimittelforschung. 1975;25(1):132.
  18. Beckmann, H., Strauss, M. A., and Ludolph, E. Dl-phenylalanine in depressed patients: an open study. J.Neural Transm. 1977;41(2-3):123-134. PubMed
  19. Sabelli, H. C., Fawcett, J., Gusovsky, F., Javaid, J. I., Wynn, P., Edwards, J., Jeffriess, H., and Kravitz, H. Clinical studies on the phenylethylamine hypothesis of affective disorder: urine and blood phenylacetic acid and phenylalanine dietary supplem
  20. Cotzias, G. C., Van Woert, M. H., and Schiffer, L. M. Aromatic amino acids and modification of parkinsonism. N Engl.J Med 2-16-1967;276(7):374-379. PubMed
  21. Kravitz, H. M., Sabelli, H. C., and Fawcett, J. Dietary supplements of phenylalanine and other amino acid precursors of brain neuroamines in the treatment of depressive disorders. J Am Osteopath.Assoc 1984;84(1 Suppl):119-123. DOI
  22. Mann, J., Peselow, E. D., Snyderman, S., and Gershon, S. D-phenylalanine in endogenous depression. Am.J.Psychiatry 1980;137(12):1611-1612. PubMed
  23. Katoulis AC, Alevizou A, Bozi E, et al. A randomized, double-blind, vehicle-controlled study of a preparation containing undecylenoyl phenylalanine 2% in the treatment of solar lentigines. Clin Exp Dermatol 2010;35(5):473-6. PubMed

See these in context on the Phenylalanine monograph →

L-tryptophan 18 references
  1. Messiha FS. Fluoxetine: adverse effects and drug-drug interactions. J Toxicol Clin Toxicol 1993;31:603-30. PubMed
  2. Devoe LD, Castillo RA, Searle NS. Maternal dietary substrates and human fetal biophysical activity. The effects of tryptophan and glucose on fetal breathing movements. Am J Obstet Gynecol 1986;155:135-9. DOI
  3. Lieberman HR, Corkin S, Spring BJ. The effects of dietary neurotransmitter precursors on human behavior. Am J Clin Nutr 1985;42:366-70. PubMed
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5-htp 32 references
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Alpha-gpc 4 references
  1. Di Perri R, Coppola G, Ambrosio LA, et al. A multicentre trial to the evaluate the efficacy and tolerability of alpha-glycerylphosphorylcholine versus cytosine diphosphocholine in patients with vascular dementia. J Int Med Res 1991;19:330-41.
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See these in context on the Alpha-gpc 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.

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