Semax is one of the most thoroughly researched nootropic peptides in neuroscience, and for good reason. It raises two of the brain’s most important growth factors, sharpens focus and memory, and protects neurons under stress, all from a compound small enough to work as a quick intranasal dose. It is one of the rare nootropics with decades of published research and real-world clinical use behind it.
What Semax is
Semax is a seven-amino-acid synthetic peptide (Met-Glu-His-Phe-Pro-Gly-Pro), derived from a fragment of ACTH known as ACTH(4-10). A Pro-Gly-Pro tail added to the end makes it resistant to rapid breakdown, which turns a short-lived hormone fragment into a stable, brain-active compound. It was developed at the Russian Academy of Sciences and has been registered for clinical use in Russia since 1996, where it is used for stroke recovery and cognitive conditions.
What the research shows
The standout finding in the Semax literature is its effect on brain growth factors. Research has shown that Semax upregulates both BDNF (brain-derived neurotrophic factor) and NGF (nerve growth factor) in key brain regions including the hippocampus and cortex. Work by Dolotov and colleagues (2003) documented increased BDNF in the hippocampus, and Shadrina and colleagues (2010) reported elevated BDNF and NGF in the frontal cortex and hippocampus within hours of a single dose. BDNF and NGF are central to neuroplasticity, the brain’s ability to strengthen connections and form memories.
The neuroprotective side is just as well studied. In models of stroke and reduced blood flow, Semax upregulated growth factors and their receptors and supported neuronal survival, which is the basis for its clinical use in Russia for stroke. The nootropic effect is notably durable for such a small peptide, lasting roughly 20 to 24 hours, and the compound also modulates dopamine and serotonin signalling, the systems tied to focus, motivation, and mood.
How it works
Semax works through the BDNF/TrkB pathway, the brain’s primary growth and repair signalling route. By raising BDNF and NGF and activating their receptors, it promotes the survival and growth of neurons and strengthens the synaptic connections behind learning and memory. Layered on top of that is its influence on dopamine and serotonin, which helps explain the sharper focus and steadier mood reported in the research. The combination of neurotrophic support and neurotransmitter modulation is what gives Semax its dual reputation as both a cognitive enhancer and a neuroprotectant.
Quick facts
| Semax | |
|---|---|
| Type | Synthetic 7-amino-acid peptide |
| Derived from | ACTH(4-10), stabilized with a Pro-Gly-Pro tail |
| Best known for | Focus, memory, and neuroprotection |
| Key mechanism | BDNF and NGF upregulation (BDNF/TrkB pathway) |
| Effect duration | Roughly 20 to 24 hours per dose |
| Often paired with | Selank |
| Form | Lyophilized powder, reconstituted before use |
What to look for when buying
For a peptide studied this carefully, the research-grade material should match the standard. Look for a Certificate of Analysis (COA) from third-party testing and an HPLC-MS purity figure of 99% or higher. Every batch of Marek Pharma’s Semax is HPLC-MS tested with a COA, lyophilized for stability, and ships from within Canada.
References
- Dolotov OV, et al. Semax, an analog of ACTH(4-10), increases BDNF in the rat hippocampus. 2003.
- Shadrina M, et al. Semax increases BDNF and NGF expression in the rat frontal cortex and hippocampus. 2010.
- Kaplan AY, et al. Semax neuroprotective and nootropic effects in clinical and experimental settings (Russian Academy of Sciences research program).
For laboratory and research use only.