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Fénix Methode

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← All supplements
Amino acidsWeak evidence

L-phenylalanine

Also known as: phenylalanine

Phenylalanine is an essential amino acid the body converts to tyrosine and then dopamine and noradrenaline. As a supplement it is poorly researched.

What it is used for

  • Mood support – weak evidence
  • Repigmentation in vitiligo (alongside treatment) – weak evidence

Forms and how they differ

L-phenylalanine

the form naturally found in protein

DL-phenylalanine

mix with the D-form, even less researched

When to take it

Morning, on an empty stomach or with a light meal.

Pairs well with

Vitamin B6.

Do not combine / separate

Avoid in the evening and do not combine with other stimulants.

Watch out for

Not suitable with phenylketonuria. Caution with antidepressants (especially MAOIs), Parkinson's medication, high blood pressure and mental health conditions. Consult your doctor or pharmacist if you are pregnant, breastfeeding, have kidney or liver disease or take any medicines.

Safety

Do not exceed the label dose.

Practical tip

For dopamine support, tyrosine is the better-researched option.

Products containing L-phenylalanine 3

L-phenylalanine 500 mgDL form · 500 mg / capsuleMoodFocus
L-phenylalanine free form 500 mgfree form · 500 mg / capsuleMoodFocus
L-phenylalanineMoodFocus
How to read the evidence rating
Strong evidenceModerate evidenceWeak evidenceNo evidence

Strong = several good human studies or official recommendations; moderate = promising but smaller studies; weak = few studies or mixed results; no evidence = claims not confirmed.

Combination check

Select the supplements you take and, if relevant, your medicines. We show what interferes, what needs a time gap and what to watch out for.

Check L-phenylalanine with others

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From the same group

Acetyl-L-carnitineWeak evidenceAlmond proteinWeak evidenceAmino acid complexWeak evidenceBCAAWeak evidenceBeef proteinModerate evidenceCaseinStrong evidence
Important notice

This information is educational and does not replace advice from a doctor or pharmacist. We do not give medicine dosages. Supplements are no substitute for a varied diet; if pregnant, breastfeeding, ill or on medication, consult a doctor first.