Semax is a synthetic brain peptide based on a fragment of ACTH (a stress hormone your body already makes). The nerds added a stabilizing tail to keep it from breaking down too fast. It's a nasal spray that gives you clean, non-jittery focus by boosting dopamine, serotonin, and BDNF (brain-derived neurotrophic factor). It's been used clinically in Russia since the 1990s for stroke rehab and cognitive decline. Think of it as the gas pedal to Selank's brake. More stimulating, more 'I need to get things done' energy. The FDA removed it from their safety concern list in April 2026, which signals a regulatory thaw. Morning dosing only. This thing will keep you up if you use it after 2pm. N-Acetyl Semax (Adamax) is the enhanced variant with longer duration and potentially greater potency.
Semax Protocol
Dose: 200-600mcg intranasal per session (up to 900mcg for neuroprotective protocols) | Frequency: 1-2 times daily, morning preferred (can disrupt sleep if taken late) | Cycle: 5 days on, 2 days off for 2-4 weeks, then 1-2 weeks off | Route: Intranasal (primary), SubQ (alternative)
Reconstitution: Primarily used as nasal spray. For SubQ: 1mL bacteriostatic water per 5mg vial. Free reconstitution calculator.
Morning dosing is important. This one is stimulating. Taking it after 2pm is asking for a rough night. The 5-on-2-off protocol is designed to keep BDNF and NGF levels elevated without desensitization.
Semax Effects
Focus & concentration (75%). Clean, non-jittery focus. People compare it to a calm Adderall without the comedown.
Memory enhancement (60%). Both working memory and recall improve. BDNF, your brain's growth and repair signal, is probably doing the heavy lifting here.
Motivation & drive (55%). More dopamine in the right places means better follow-through on tasks. Not euphoric, just less friction.
Neuroprotection (40%). The stroke recovery data suggests real neuroprotective effects, not just cognitive enhancement.
Semax Side Effects
Headache (15%). Mild headache the first few days. Most common complaint. Usually gone by day three or four.
Sleep disruption (12%). Almost always because you used it too late in the day. Keep it to mornings and this isn't a problem.
Nasal irritation (10%). Standard nasal spray irritation. Nothing you haven't felt with Flonase.
Irritability (8%). Higher doses can make you snappy or emotionally reactive. That's a sign to dial it back.
Semax Dosing by Use Case
Condition
Dose
Duration
Notes
Focus and cognitive performance
200-400mcg intranasal, 1-2x/day
5 days on, 2 off, for 2-4 weeks
The primary use case. Clean focus through higher dopamine and BDNF (your brain's growth signal). Morning dosing only. Pairs well with Selank if the focus comes with edginess. Start at 200mcg and adjust. More isn't always better here.
Neuroprotection and stroke recovery
600-900mcg intranasal, 2x/day
10-14 days (Russian clinical protocol)
The clinical indication in Russia. Higher doses for neuroprotective effects. The controlled trial in ischemic stroke patients showed significant improvement at day 30. This is medical territory. Work with a clinician.
BDNF upregulation (neuroplasticity)
300-600mcg intranasal, 1x/day
2-4 weeks, cycling 5 on/2 off
Semax increases BDNF 1.4x and BDNF mRNA 3x in animal studies. BDNF helps your brain build new connections, lock in memories, and stay adaptable. This is the long-game nootropic angle. Combine with learning or skill acquisition for maximum effect.
Motivation and task initiation
200-400mcg intranasal, morning only
As needed or cycled 5/2
The dopaminergic boost helps with the 'just start' problem. Not a replacement for good habits, but it reduces the friction between intending to do something and actually doing it. Lower doses are usually enough for this.
Semax Results Timeline
Day 1-3, Onset: Effects are felt within 15-30 minutes of intranasal administration. Mild headache is common the first 2-3 days. Focus and alertness noticeably sharper. Some people feel overstimulated at first. Lower the dose if so.
Day 3-7, Stabilization: Headaches resolve. The focus effect becomes more consistent and less 'buzzy'. Working memory improvements noticeable. Motivation and task follow-through improve. This is where the BDNF upregulation starts accumulating.
Week 2-3, Peak cognitive benefits: Full nootropic effect. Memory, focus, and verbal fluency at their best. The neuroprotective benefits are building in the background. Mood tends to be more even and proactive. Some people describe it as 'mental clarity without trying.'
Week 3-4+, Cycle off: Take 1-2 weeks off to prevent receptor desensitization. BDNF effects linger for days after stopping. No withdrawal symptoms. Some people notice a subtle dip in focus during the off period, but it's mild. The break keeps the next cycle effective.
Frequently Asked Questions About Semax
What is Semax?
Semax is a 7-amino-acid synthetic peptide based on a chunk of ACTH (a stress hormone your brain already makes). They added a stabilizing tail so it doesn't break down too fast. It was developed at the Institute of Molecular Genetics in Russia and has been approved there since the 1990s for stroke recovery and cognitive enhancement. It works by increasing BDNF (brain-derived neurotrophic factor), dopamine, and serotonin activity. The result is clean focus and improved memory without stimulant side effects. The FDA removed it from their safety concern list (Category 2) in April 2026.
What is the best Semax dosage?
Intranasal: 200-600mcg per dose, 1-2 times daily. Morning only. Start at 200mcg and increase if needed. The Russian clinical protocols go up to 900mcg for neuroprotective indications, but most nootropic users stay in the 200-400mcg range. SubQ: same dosing, but less clinical data for this route with Semax. Cycle 5 days on, 2 days off, for 2-4 weeks, then take 1-2 weeks off.
What are the side effects of Semax?
Headache (15%) in the first few days, nasal irritation (10%) from the spray, irritability (8%) at higher doses, and sleep disruption (12%) if you dose too late in the day. The irritability is a sign you're taking too much. The sleep disruption is almost always a timing issue, not a dose issue. Keep it to mornings and it resolves. No dependency, no withdrawal, no cognitive impairment.
Semax vs Selank: what's the difference?
Same research institute, opposite functions. Semax is the stimulant: dopamine, BDNF, focus, motivation, mental horsepower. Selank is the anxiolytic: GABA, serotonin, calm, anxiety reduction, emotional resilience. Semax alone can feel edgy or overstimulating. Selank alone can feel too mellow for some. Together they balance each other. Semax in the morning for drive, Selank throughout the day for calm. The classic Russian nootropic stack.
What is N-Acetyl Semax (Adamax)?
N-Acetyl Semax is Semax with an acetyl group added to the N-terminus. This makes it stronger, longer-lasting, and more stable. Adamax goes one step further: it's N-Acetyl Semax with an additional amidation modification. The community reports Adamax as the strongest variant with the longest-lasting effects. There are no published clinical trials comparing the variants head-to-head. The dosing is typically lower for N-Acetyl Semax and Adamax (100-300mcg) due to the increased potency.
Semax nasal spray vs injection: which is better?
Intranasal is the clinically validated route. All Russian trial data uses nasal delivery. Semax crosses the blood-brain barrier efficiently through nasal mucosa. Onset is 15-30 minutes. SubQ injection also works and may have more consistent bioavailability, but it has less clinical backing for Semax specifically. Most people use intranasal because it's simpler and has the evidence behind it. If you're already injecting other compounds, SubQ is fine.
How do you reconstitute Semax?
For SubQ injection: add 1mL of bacteriostatic water to a 5mg vial. That gives you 5mg per mL (5,000mcg per mL). For a 200mcg dose, draw 4 units on a U-100 insulin syringe. For 400mcg, draw 8 units. For intranasal use, reconstitution depends on your spray bottle delivery volume. A standard metered nasal spray delivers about 100mcg per spray. Refrigerate after reconstitution. Use within 14-21 days.
Does Semax increase BDNF?
Yes. Animal studies show Semax increases BDNF protein levels 1.4x and BDNF mRNA expression 3x in the hippocampus. BDNF (brain-derived neurotrophic factor) is the brain's growth and repair signal. It supports synapse formation, memory consolidation, and neural plasticity. This BDNF upregulation is likely the mechanism behind Semax's memory and neuroprotective effects. It also boosts NGF (nerve growth factor, the signal that keeps your neurons healthy). No human BDNF measurement studies have been published.
Emerging evidence. Decades of Russian clinical use for stroke recovery and cognitive enhancement. A controlled trial showed significant improvement in ischemic stroke patients at day 30. Increases BDNF 1.4x and BDNF mRNA 3x in rat hippocampus. FDA removed it from Category 2 (safety concern list) in April 2026, signaling a regulatory thaw.
Approval status: Approved in Russia and Ukraine. Removed from FDA Category 2 April 2026.
References
Dolotov OV, Karpenko EA, Inozemtseva LS, et al. Semax, an analog of ACTH(4-10) with cognitive effects, regulates BDNF and trkB expression in the rat hippocampus. Brain Res, 2006. PMID 16996037
Eremin KO, Kudrin VS, Saransaari P, et al. Semax, an ACTH(4-10) analogue with nootropic properties, activates dopaminergic and serotoninergic brain systems in rodents. Neurochem Res, 2005. PMID 16362768
Gusev EI, Martynov MY, Kostenko EV, et al. The efficacy of semax in the treatment of patients at different stages of ischemic stroke. Zh Nevrol Psikhiatr Im S S Korsakova, 2018. PMID 29798983
Dmitrieva VG, Povarova OV, Skvortsova VI, et al. Semax and Pro-Gly-Pro activate the transcription of neurotrophins and their receptor genes after cerebral ischemia. Cell Mol Neurobiol, 2010. PMID 19633950
Shadrina M, Kolomin T, Agapova T, et al. Comparison of the temporary dynamics of NGF and BDNF gene expression in rat hippocampus, frontal cortex, and retina under Semax action. J Mol Neurosci, 2010. PMID 19662538
Inozemtseva LS, Karpenko EA, Dolotov OV, et al. Antidepressant-like and antistress effects of the ACTH(4-10) synthetic analogs Semax and Melanotan II on male rats in a model of chronic unpredictable stress. Eur J Pharmacol, 2024. PMID 39442746
Iasnetsov VV, Voronina TA. Comparative study of the antiamnesic activity of nootropic and neuroprotective agents. Eksp Klin Farmakol, 2009. PMID 19803357
Storage
Lyophilized: Refrigerate at 2-8C or freeze at -20C for long-term. Stable 2+ years frozen.
Reconstituted: Refrigerate and use within 14-21 days. Do not freeze.
Water: Bacteriostatic water for SubQ. Nasal formulations use preserved saline.
Needle: 30-31 gauge, 0.5 inch for SubQ if not using nasal spray.
These statements have not been evaluated by the FDA. This content is for educational purposes only. Consult a healthcare professional before starting any protocol. vialprep sells injection supplies, not compounds.
