Cerebrolysin vs Selank

Cerebrolysin

Cerebrolysin is not a single peptide. It is a standardised enzymatic hydrolysate of purified porcine brain protein containing low-molecular-weight neuropeptides and free amino acids, so no single half-life or molecular weight applies. DOSING CONVENTION: it is supplied as a ready-made sterile solution at 215.2 mg of peptide concentrate per mL, in sealed ampoules of 1, 2, 5, 10 and 20 mL, and it is prescribed in mL, never in mcg. The figures in this entry are the mg equivalents of that solution converted to mcg for consistency with the rest of the dataset: 215,200 mcg = 1 mL, 430,400 mcg = 2 mL, 1,076,000 mcg = 5 mL. It is NOT reconstituted, so the vial sizes above are ampoule contents and the bacteriostatic water field does not apply. Route matters: 5 mL is the practical ceiling for a single intramuscular injection, and the larger doses used in trials (10-50 mL/day) are given as slow intravenous infusions in a clinical setting, not IM. It is approved in a number of European, Asian and CIS countries but is NOT FDA approved. Human evidence is more substantial than for the other compounds in this class - randomized trials and Cochrane reviews in acute ischaemic stroke, vascular dementia, Alzheimer disease and traumatic brain injury - but the results are mixed, the stroke reviews found no convincing benefit on death or dependency, and much of the trial base is manufacturer-sponsored. Courses are conventionally given 5 days a week for about 4 weeks rather than continuously.

Selank

A synthetic heptapeptide analogue of the immune peptide tuftsin, again with a Pro-Gly-Pro tail added for stability. Its character is anxiolytic rather than stimulant, which is why it is usually paired with, not substituted for, Semax. Like Semax it is a Russian-registered intranasal medicine (commonly a 0.15% solution) and is NOT approved in the US or EU; the human evidence is small Russian trials in generalised anxiety disorder and adjustment disorder, some comparing it against benzodiazepines such as phenazepam, and it has not been independently replicated in Western trials. Route matters: it is an intranasal drug, not an injectable. Russian clinical dosing runs to roughly 1800-2700 mcg per day divided across two or three administrations; the per-dose range here reflects the more conservative doses typical of non-clinical use rather than the full trial daily total. Plasma half-life is minutes, so no hourly figure is listed. Courses are conventionally short (10-14 days) rather than continuous.