Amino Acid
L-Phenylalanine
Also known as: Phenylalanine, Phe, DL-Phenylalanine, DLPA
B
Evidence
Essential amino acid and precursor to tyrosine, dopamine, and other catecholamines. Important for mood, cognitive function, and pain modulation.
Primary uses
- Mood support
- Cognitive function
- Pain management (DLPA)
- Dopamine precursor
How it works
- Converted to L-tyrosine by PAH enzyme
- Precursor to dopamine, norepinephrine, epinephrine
- D-form inhibits enkephalin degradation
- Supports melanin synthesis
Dosage
- Typical range
- 500-2000 mg daily
- Timing
- On empty stomach for mood effects
- With food
- Without for absorption
- Duration
- Cycle for mood use
- Special populations
- Not for PKU patients
Forms
- Capsule
- Powder
Safety
Common side effects
- Headache
- Anxiety at high doses
Contraindications
- Phenylketonuria (PKU)
- MAOIs
Evidence notes
Established precursor role in neurotransmitter synthesis
Grade B: Some human trials support key claims; further confirmation needed.
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