Neuropeptides Clinical use

Semax

Also known as: Semaks, Met-Glu-His-Phe-Pro-Gly-Pro

Semax is a synthetic heptapeptide derived from an ACTH (4-10) fragment with an added Pro-Gly-Pro sequence that increases its stability. It was developed in Russia, where it is approved as a nootropic and neuroprotective agent. It is used to improve cognitive function, memory and recovery after cerebral ischemic events.

Mechanism of action

Semax modulates several neurotransmission systems and neurotrophic factors.

BDNF and NGF: increases expression of brain-derived neurotrophic factor and nerve growth factor.
Dopaminergic and serotonergic systems: modulates their activity, improving attention and mood.
Neuroprotection: reduces oxidative stress and limits ischemic damage.

Uses & indications

Cognitive impairment and memory/attention enhancement.
Ischemic stroke and neurological recovery (approved use in Russia).
Anxiety disorders and as a nootropic (off-label).

Effects

Intended effects: improved focus, memory and mental clarity, neuroprotective effect and mild anxiolytic action.

Adverse effects: generally well tolerated; occasionally nasal irritation (intranasal route), mild headache or insomnia if used late.

Considerations & contraindications

Not approved by FDA/EMA; approved in Russia and some regional countries.
Long-term safety data limited outside Russian studies.
Caution when combined with stimulants or antidepressants.

Regulatory approval

Approved and marketed in Russia as a nootropic/neuroprotective drug. No FDA/EMA approval.

Dosage

Intranasal solutions of 0.1%–1% are commonly used. This is not a clinical recommendation.

Storage

Lyophilized: 2–8 °C. Intranasal solution: refrigerate and use within a few weeks; protect from light.

Technical data

Regulatory status Clinical use

Molecular weight 813.9 Da

Half-life Muy corta en plasma (minutos); efecto central prolongado

Administration routes Intranasal, subcutánea