Sourcing notes for these two:

Selank and Semax are somewhat niche compared to mainstream peptides like BPC-157 or TB-500. You can find them from:

• Russian pharmacies: Available as prescription products (Selank nasal drops 0.15%, Semax nasal drops 0.1% and 1%). Some people order directly from Russian online pharmacies with varying success on delivery to Western countries.
• US peptide suppliers: A few carry them in lyophilized form for research purposes. Purity verification is important here — ask for CoA with HPLC and MS data.

The Russian pharmacy versions come pre-made as nasal sprays, which is convenient. The research peptide versions require reconstitution — typically with bacteriostatic water or sterile saline, then transferred to a nasal spray bottle.

Selank typical intranasal dose: 200-600 mcg/day
Semax typical intranasal dose: 200-900 mcg/day

These are relatively affordable peptides. A month's supply of Selank from a US source runs $40-70.

Really interesting thread. Has anyone tried NA-Selank (N-Acetyl Selank Amidate)? I've seen it marketed as a more stable, longer-acting version of Selank. Is there any actual data on it or is it just a vendor marketing play? 🤔

NA-Selank Amidate is a modified version with an N-acetyl group and C-terminal amidation to resist enzymatic degradation. The theory is that it has a longer half-life and better bioavailability.

Is there published clinical data on NA-Selank specifically? Not that I'm aware of. The modifications are standard peptide chemistry approaches to improving stability, and they're reasonable from a pharmacological standpoint. But the clinical data from Russia is on regular Selank.

I've tried both. Subjectively, NA-Selank feels somewhat more potent at equivalent doses and the effects seem to last a bit longer (maybe 5-6 hours vs 3-4 hours for regular Selank). But that's n=1 anecdote.

If you're new to these peptides, start with regular Selank since that's what has the clinical data behind it. If you find it helpful but want longer duration, then consider trying the NA version.

Ordered Selank from a US supplier. Going to start with 300 mcg intranasal daily and see how it interacts with my tirze regimen over the next month. Will keep the thread updated. Thanks everyone for the thorough responses — this community continues to impress. 🙏