Noopept vs Semax
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
Noopept
Noopept (N-phenylacetyl-L-prolylglycine ethyl ester) is a peptide-derived nootropic developed in Russia. While technically a dipeptide prodrug rather than a true peptide, it's often discussed alongside peptide nootropics.
Full details →Semax
Semax is a synthetic peptide derived from ACTH (adrenocorticotropic hormone). Developed in Russia as a nootropic and neuroprotective agent.
Full details →Side-by-Side Comparison
| Aspect | Noopept | Semax |
|---|---|---|
| Mechanism | Metabolized to cycloprolylglycine which modulates AMPA and NMDA receptors, increases NGF and BDNF expression, and provides neuroprotective effects through antioxidant mechanisms. | Enhances BDNF expression, modulates dopamine and serotonin systems, and provides neuroprotective effects. Increases attention, memory formation, and learning. |
| Typical Dosage | Oral: 10-30mg daily, typically divided into 2-3 doses. Sublingual use may enhance absorption. Some users go higher but effects may plateau. | Intranasal: 200-600mcg 2-3 times daily. Higher doses (up to 1mg) used in clinical settings for stroke recovery. |
| Administration | Oral or sublingual administration. Unlike most peptides, it's orally bioavailable. Can be taken with or without food. | Primarily administered intranasally. N-Acetyl Semax Amidate (NASA) is a modified version with enhanced stability and potency. |
| Side Effects | Headache (often from choline depletion), irritability, insomnia if taken late, and occasional brain fog during initial use. | Generally well-tolerated. May cause mild irritability or hair shedding in some users. |
| Best For |
What They Have in Common
Both Noopept and Semax are commonly used for: