Phenylalanine + Amoxapine
Amoxapine brand name: Asendin.
We found no known interaction between Phenylalanine and Amoxapine in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.
Phenylalanine and Amoxapine
We checked these two against our interaction database. Here is what we found.
No Known Interaction Found
We did not find a documented interaction between Amoxapine and Phenylalanine in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.
If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.
Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.
Phenylalanine safety at a glance
Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.
Why No Interaction Is Listed for Amoxapine
Interactions in our licensed database are recorded against drug classes, not just single drug names. Amoxapine is filed under 6 classifications — including tricyclic antidepressants (tcas), antidepressant drugs, serotonergic drugs. Phenylalanine has documented interactions with 3 drug classes — the most serious being levodopa (major), baclofen (moderate) and monoamine oxidase inhibitors (maois) (moderate) — and none of Amoxapine’s classifications are among them.
Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.
Phenylalanine Does Interact With Other Medications
Phenylalanine has 5 major, 11 moderate known drug interactions in our database — Amoxapine isn’t one of them. If you take anything else, check it against the full list below.
Check Another of Your Medications Against Phenylalanine
We haven’t checked that one against Phenylalanine yet — ask our pharmacists directly.
Covers the 2,830 medications we’ve checked against Phenylalanine. Pick one to open its full report.
Phenylalanine in Pregnancy & Breastfeeding
When L-phenylalanine is consumed in amounts typically found in foods by pregnant patients with normal phenylalanine metabolism.
When L-phenylalanine is consumed in amounts typically found in foods by pregnant patients with high serum phenylalanine concentrations, such as those with phenylketonuria (PKU). Serum levels of phenylalanine greater than 360 micromol/L increase the risk of birth defects. Experts recommend that patients with high phenylalanine serum concentrations follow a low phenylalanine diet for at least 20 weeks prior to conception to decrease the risk for birth defects. There is insufficient reliable information available about the safety of L-phenylalanine when taken by mouth in large doses during pregnancy; avoid using. There is insufficient reliable information available about the safety of oral D-phenylalanine during pregnancy; avoid using.
When L-phenylalanine is consumed in amounts typically found in foods by breast-feeding patients with normal phenylalanine metabolism. There is insufficient reliable information available about the safety of L-phenylalanine when taken by mouth in medicinal amounts during lactation; avoid using. There is insufficient reliable information available about the safety of oral D-phenylalanine during lactation; avoid using.
DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center
What Amoxapine Is Prescribed For, and What Phenylalanine Has Been Studied For
These two come up together because they touch the same health topic — not because they do the same job. Amoxapine is a prescription medicine with approved uses on its FDA label. Phenylalanine is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.
Amoxapine is prescribed for: Amoxapine is used to treat symptoms of depression. This includes neurotic or reactive depression (depression triggered by life events), as well as endogenous depression (depression that arises from within, without a clear external cause) and psychotic depression. It is also indicated for depression that comes with significant anxiety or agitation.
Phenylalanine has been studied for:
-
Depression studied, not established Phenylalanine has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows
Phenylalanine for depression
It is unclear if oral phenylalanine is beneficial in patients with depression.
Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Amoxapine on your own; if you are taking Phenylalanine for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.
See Every Supplement That Interacts With Amoxapine
This page covers Phenylalanine only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Amoxapine page lists 68 supplements it has a documented interaction with, worst first, each one explained.
The most serious there right now: Activated Charcoal (major), Lithium (major), Scopolia (major), 5-htp (moderate) and Acetyl-l-carnitine (moderate).
By severity: 3 major · 49 moderate · 16 minor.
From our pharmacist’s overview on the Amoxapine page
“Amoxapine (Asendin) is an older tricyclic antidepressant, and its supplement list deserves real care. Three of the 68 ingredients on file are rated major: activated charcoal can soak up the drug before your body gets it, lithium raises the risk of serotonin syndrome (a dangerous serotonin overload), and scopolia piles onto amoxapine's…”
Reviewed by 2 · Jul 18, 2026
Taking Phenylalanine as Part of a Dietary Supplement Product? Check It for Interactions
We hold 1,990 real supplement products containing Phenylalanine, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Phenylalanine. Even though Phenylalanine itself has no known interaction with Amoxapine, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:
Where Phenylalanine and Amoxapine Sit Against Everything Else
Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.
#133 of 1,452 supplements looked up here in the last 7 days
#1,134 of 2,830 medications looked up here in the last 7 days
Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.
Where does our data come from?
- Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
- Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Phenylalanine reference on this page ↓
- Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Phenylalanine and Amoxapine records this page draws on were last updated July 11, 2026.
- What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
About Phenylalanine
What is Phenylalanine?
- Depression and mood
- Skin condition vitiligo
- Pain conditions
- Attention and focus
- Appetite control
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 limited or mixed. People with the genetic condition PKU must strictly avoid it.
Amino acid (not a plant part) · Capsules, tablets, powder
An interaction check asks whether these two react with each other — it does not ask whether Phenylalanine is a good idea for someone in your situation. Here is what our Phenylalanine record says about it on its own.
Phenylalanine: dosing
There is no well-established standard supplement dose for phenylalanine, and the right amount may differ depending on the form (L-, D-, or DL-) and the reason for use.If you choose to use a product, follow the directions on the label and do not exceed the recommended amount.
From our Phenylalanine monograph — the full record covers uses, side effects and every documented interaction.
About Amoxapine
What Is Amoxapine Used For?
Brand name: Asendin
Amoxapine is used to treat symptoms of depression. This includes neurotic or reactive depression (depression triggered by life events), as well as endogenous depression (depression that arises from within, without a clear external cause) and psychotic depression.
It is also indicated for depression that comes with significant anxiety or agitation.
Other Drugs & Phenylalanine
Browse every other medication we’ve checked against Phenylalanine — both the ones with a known interaction and the ones without. Select any drug for the full detail.
No drugs match “”.
5 interactions
11 interactions
No interaction 2,813 drugs checked — show the list
We also checked Phenylalanine against these medications and found no known interaction in our sources. Open any page to confirm.
- Apixaban ›
- Levothyroxine ›
- Amlodipine ›
- Methylphenidate ›
- Warfarin ›
- Sertraline ›
- Losartan Potassium ›
- Testosterone ›
- Ivermectin ›
- Aspirin ›
- Abemaciclib ›
- Acetaminophen ›
- Metoprolol ›
- Rosuvastatin ›
- Rivaroxaban ›
- Escitalopram ›
- Clopidogrel ›
- Atorvastatin ›
- Docusate ›
- Tadalafil ›
- Tirzepatide ›
- Methamphetamine ›
- Ibuprofen ›
- Valacyclovir ›
- Warfarin Sodium ›
- Hydroxyurea ›
- Sumatriptan ›
- Semaglutide ›
- Prednisone ›
- Lisdexamfetamine ›
- Propranolol ›
- Metformin ›
- Amitriptyline ›
- Amoxicillin ›
- Lisinopril ›
- Isotretinoin ›
- Amlodipine Besylate ›
- Methotrexate ›
- Bendamustine ›
- Bupropion ›
- Doxycycline ›
- Fluoxetine ›
- Acyclovir ›
- Azithromycin ›
- Pregabalin ›
- Lamotrigine ›
- Dextroamphetamine ›
- Gabapentin ›
- Acetaminophen, Codeine ›
- Levothyroxine, Liothyronine ›
- Clonazepam ›
- Quetiapine ›
- Naproxen ›
- Omeprazole ›
- Letrozole ›
- Duloxetine ›
- Methylene Blue ›
- Buspirone ›
- Citalopram ›
- Ciprofloxacin ›
Showing the 60 most looked-up of 2,813 medications checked with no known interaction — see the full Phenylalanine list.
Phenylalanine References
The 23 references that drive our Phenylalanine monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.
- 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
- Sturtevant FM. Use of aspartame in pregnancy. Int J Fertil 1985;30:85-7.
- Silkaitis RP, Mosnaim AD. Pathways linking L-phenylalanine and 2-phenylethylamine with p-tyramine in rabbit brain. Brain Res 1976;114:105-15.
- 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
- Mosnik DM, Spring B, Rogers K, Baruah S. Tardive dyskinesia exacerbated after ingestion of phenylalanine by schizophrenic patients. Neuropsychopharmacology 1997;16:136-46. PubMed
- Siddiqui AH, Stolk LM, Bhaggoe R, et al. L-phenylalanine and UVA irradiation in the treatment of vitiligo. Dermatology 1994;88:215-8. PubMed
- 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
- 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
- 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
- Juncos JL, Fabbrini G, Mouradian MM, et al. Dietary influences on the antiparkinsonian response to levodopa. Arch Neurol 1987;44:1003-5. PubMed
- 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
- Baker GB, Bornstein RA, Rouget AC, et al. Phenylethylaminergic mechanisms in attention-deficit disorder. Biol Psychiatry 1991;29:15-22.. PubMed
- Wood DR, Reimherr FW, Wender PH. Treatment of attention deficit disorder with DL-phenylalanine. Psychiatry Res 1985;16:21-6.. PubMed
- 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
- Cederbaum S. Phenylketonuria: an update. Curr Opin Pediatr 2002;14:702-6. PubMed
- 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
- Fischer, E., Heller, B., Nachon, M., and Spatz, H. Therapy of depression by phenylalanine. Preliminary note. Arzneimittelforschung. 1975;25(1):132.
- 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
- 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
- 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
- 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
- Mann, J., Peselow, E. D., Snyderman, S., and Gershon, S. D-phenylalanine in endogenous depression. Am.J.Psychiatry 1980;137(12):1611-1612. PubMed
- 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
Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.
Amoxapine Is Linked to Lower Levels of 3 Nutrients
Natural Medicines records Amoxapine as a medicine that can lower these. This is not an interaction with Phenylalanine — it is a separate effect of the medicine, and it is a reason some people are advised to supplement rather than to avoid one:
Read the full Amoxapine nutrient depletion report ›
Depletion records come from the licensed Natural Medicines database. Do not start a supplement on the strength of this page — ask your pharmacist or doctor whether it applies to you.
Taking Phenylalanine and Amoxapine Together: Common Questions
Is it safe to take Phenylalanine with Amoxapine?
Do Phenylalanine and Amoxapine have any of the same side effects?
Are Phenylalanine and Amoxapine used for the same thing?
How was the Phenylalanine and Amoxapine combination checked?
Does Phenylalanine interact with any other medications?
Does Amoxapine interact with any supplements?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.