Semax
Russian-developed neuropeptide; Limited Western clinical confirmation
Brief Overview: Semax is an ACTH 4-10 analog designed to keep neuroactive properties without broad endocrine ACTH effects. It is used intranasally in Russian medical practice for neurologic and cognitive indications. Evidence lens: The key evidence issue is transferability. Russian clinical use and mechanistic studies are relevant, but don't assume the same regulatory, manufacturing, or trial standards as an FDA-approved neurologic drug. How to read this: if you're new, distinguish Semax from Adamax and N-acetyl Semax amidate; Small modifications can change stability and potency. Once you're past the basics, look for objective endpoints: stroke recovery scales, attention testing, retinal outcomes, and verified molecule identity on COA.
- Semax is a synthetic heptapeptide analog of a fragment of the Adrenocorticotropic Hormone (ACTH 4-10).
- It was developed in the 1980s and 90s by the Institute of Molecular Genetics of the Russian Academy of Sciences.
- Unlike the parent hormone, Semax has no endocrine (hormonal) activity.
- It is classified as a nootropic and neuroprotective agent and has been included on the Russian List of Vital and Essential Drugs since 2001.
- Semax is an ACTH(4-10)-derived heptapeptide analog used intranasally in regional neuro contexts. It is not interchangeable with Adamax or every Semax derivative.
- Semax works through several pathways to enhance brain function and protect neural tissue: BDNF & NGF Induction: It significantly increases the expression of Brain-Derived Neurotrophic Factor (BDNF) and Nerve Growth Factor (NGF) in the hippocampus and cerebral cortex, which are critical for neuroplasticity and neuron survival.
- Melanocortin System Modulation: It acts on melanocortin receptors (specifically MC4 and MC5) in the brain, which helps regulate focus, learning, and neuroinflammation. Dopamine &
- Serotonin Stabilization: It prevents the breakdown of enkephalins and modulates the levels of dopamine and serotonin, leading to improved mood and motivation.
- Transcription Factor Activation: It influences the expression of genes involved in the vascular system and immune response in the brain, particularly during periods of hypoxia (low oxygen).
- Mechanisms include melanocortin-related signaling, BDNF/neurotrophin modulation, neuroprotection, and monoamine/cognitive effects. It is not a stimulant in the classic amphetamine sense. The mechanism here is a plausibility map, not proof of a clinical outcome.
- Stroke Recovery: Widely used clinically to reduce the volume of brain damage after an ischemic stroke and to accelerate the recovery of motor and cognitive functions. ADHD &
- Focus: Research indicates that Semax improves attention span and memory in individuals with ADHD and healthy subjects under high-stress/high-workload environments.
- Neuroprotection: Studies show it protects neurons against oxidative stress, glutamate excitotoxicity, and heavy metal toxicity.
- Optic Nerve Repair: Evidence suggests Semax can be used to treat optic nerve damage (glaucoma or optic neuropathy) by improving retinal cell survival.
- There is regional human literature and growing preclinical work, but not FDA-level proof for cognition or stroke recovery. The best wording is studied but not broadly approved. These are separate tiers of evidence: preclinical data, regional human reports, approved-product evidence, and community anecdotes.
Below you'll find reported clinical-label, research, and community-use dosing contexts where available. It's educational reference only, not dosing instructions for you.
- Protocol 1: Clinical/Trial Protocols [Clinical/Human Trial]; Route: Intranasal spray; Dose: 0.1% Solution: 2–3 drops per nostril (2–3× daily); 1.0% Solution: 1–2 drops per nostril (Acute stroke); Frequency: 2 to 3 times daily; Timing: Post-stroke or early morning; Duration: 10 to 14 days; Status: No - research, clinical trial, off-label, community/anecdotal, cosmetic, or otherwise not FDA-approved as written.
- Protocol 2: Common Biohacker Protocols [Community/Biohacker/Anecdotal]; Route: Intranasal spray; Dose: 0.1%: 200 mcg – 600 mcg (per dose); 1.0%: 1 mg – 2 mg (Advanced use); Frequency: 1 to 2 times daily; Timing: Morning or prior to deep work; Duration: 2 to 4 weeks; Status: No - research, clinical trial, off-label, community/anecdotal, cosmetic, or otherwise not FDA-approved as written.
- Protocol 3: Subcutaneous injection note [Community/Biohacker/Anecdotal]; Route: Subcutaneous (SC); Dose: 100 mcg – 500 mcg; Status: No - research, clinical trial, off-label, community/anecdotal, cosmetic, or otherwise not FDA-approved as written.
- Intranasal use is the main practical route. Spray concentration, total daily volume, and nasal technique determine actual exposure. Protocol rows are educational context, not personalized instructions, and product-label directions control when an approved product exists.
- Time until steady state: not calculable.
- Half-life basis: Very short systemic exposure is often described, but reliable human PK is limited. Intranasal CNS-effect claims are pharmacodynamic, not a stable plasma concentration target.
- Beginner translation: this is a deliberately conservative read. A missing steady-state number does not mean the compound has no effect; It means the available human PK data are not strong enough to justify a precise accumulation estimate for common use patterns.
- Half-life: Very short systemically (minutes), but its influence on BDNF and gene expression lasts for 20-24 hours.
- Delivery: intranasal is the best Semax-specific route in the guide, but it is potential CNS-relevant nasal delivery rather than guaranteed direct-to-brain targeting. It is stable at room temperature for short periods but is best stored in the refrigerator for long-term use.
- Semax is short-lived, but downstream neurotrophin/gene-expression effects may last longer than plasma exposure. Do not equate half-life with duration of perceived focus. PK estimates are most useful for timing and accumulation awareness, not for proving efficacy or safety.
- Selank: Frequently stacked with Selank. Semax provides the “gas” (focus/energy), while Selank provides the “brake” (calm/anxiety reduction), creating a balanced flow state.
- Stimulants: Often used to mitigate the “crash” from caffeine or ADHD medications due to its dopamine-stabilizing properties.
- Cerebrolysin: Combined in Russian hospitals for severe neurological rehabilitation.
- Often paired with Selank, nootropics, cholinergics, or mitochondrial/NAD strategies. Start singly when evaluating attention, anxiety, or sleep effects. A sound stack accounts for both mechanism overlap and additive safety, tolerability, and interpretation risks.
- Side Effects: Extremely well-tolerated. Rare reports of mild irritation of the nasal mucosa, transient headaches, or irritability if the dose is too high.
- Hair Loss Concern: A common (though largely anecdotal) concern in the biohacking community is that increased BDNF could potentially accelerate hair thinning in those predisposed to MPB; However, this is not reflected in clinical literature.
- Contraindications: History of seizures (threshold may be lowered) and pregnancy/breastfeeding.
- Possible adverse effects include headache, irritability, insomnia, anxiety shift, nasal irritation, and blood-pressure sensitivity in susceptible users. Long-term data are limited. The honest safety picture covers both known risks and uncertainty risks, especially where human data are limited.
- Cognitive Tasks: Monitoring “time to completion” and error rates in complex tasks.
- Mood Tracking: Observation of anxiety levels and emotional resilience during high-stress periods.
- Sleep Quality: Ensuring the stimulatory effect does not lead to late-night insomnia.
- Track attention tasks, mood, anxiety, sleep latency, headache, nasal irritation, and timing relative to caffeine/stimulants. Use baseline comparisons. Useful monitoring matches the claimed goal, the most plausible risk, and objective baseline measures.
- FDA: Semax was among the 12 peptides HHS removed from Category 2 on April 15, 2026. Scheduled for specific PCAC review on July 24, 2026 for the indications of cerebral ischemia and trigeminal neuralgia (FDA Docket FDA-2025-N-6895). Compounding-pharmacy access remains blocked pending final FDA action.
- Russia: Registered since 1994 for stroke rehabilitation.
- WADA: Not currently prohibited (has been subject to periodic reconsideration).
- Semax is not FDA-approved. PCAC review relates to compounding-list status, not approval as a cognitive drug. Regulatory status spans distinct categories: FDA approval, ex-U.S. approval, investigational development, compounding review, supplement/cosmetic status, and RUO-market availability.