Acetyl-L-Carnitine is the acetylated form of L-carnitine. The acetyl group makes it lipophilic enough to cross the blood-brain barrier.
Mechanism — Carnitine shuttles long-chain fatty acids into mitochondria for beta-oxidation. ALCAR additionally provides acetyl groups for acetylcholine synthesis and mitochondrial energetics in CNS. Modulates cerebral blood flow and BDNF in research models.
Use case — Cognitive support, mild peripheral neuropathy, and adjunct in fatigue protocols. Typical 500-2,000 mg/day, split AM/midday.
Caveats — Late-day dosing can disturb sleep. Mild fishy odor at higher doses (TMAO production). Trial individually — responses vary widely.