ALCAR (Acetyl-L-Carnitine)
Acetylated L-Carnitine. Crosses the blood-brain barrier. The cognitive sibling of L-Carnitine, same shuttle role plus a brain layer.
What it actually is
Not a peptide. ALCAR is L-Carnitine with an acetyl group attached, which lets it cross the blood-brain barrier where regular L-Carnitine can't go efficiently. The acetyl group also serves as a precursor for acetylcholine in cholinergic neurons.
Why peptide users come across it
Mechanism
Same carnitine shuttle role in mitochondria as L-Carnitine. Brain-specific: donates acetyl groups for acetylcholine synthesis, modulates NGF signaling, and supports neuronal mitochondrial biogenesis, relevant to age-related cognitive decline research.
Documented dose range
Side effects
- Mild stimulation / anxiety in sensitive users
- Insomnia if taken late
- Headache on high doses
- Mild GI upset
Contraindications
- Bipolar disorder (rare reports of mania induction)
- Active hyperthyroidism
- Pregnancy (insufficient data)
The Pepdex take
Pair with ALA (alpha-lipoic acid), the Ames lab combo is the most-replicated effect. Take with breakfast, second dose by 1pm latest. If you feel wired or anxious at 1g, drop to 500mg, ALCAR is dose-sensitive. Don't substitute for L-Carnitine if your goal is fat oxidation; ALCAR is for the cognitive role.
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