Semax

Semax is a chain of seven amino acids developed by Russian researchers, whose first published accounts date to the 1990s and describe fifteen years of design work before that. It takes a four-amino-acid piece of ACTH, adrenocorticotropic hormone, the pituitary hormone that normally tells the adrenal glands to make cortisol, and bolts a three-amino-acid tail called Pro-Gly-Pro onto the end so that the body's enzymes break it down more slowly. The ACTH fragment used is the part associated in older research with learning and attention rather than with the adrenal glands, which is why the literature calls Semax a behaviourally active analogue rather than a hormone. Russian papers refer to it as a registered domestic drug given as a 1 percent intranasal solution in ischaemic stroke, cerebrovascular disease and optic nerve disorders. It is not approved by the US Food and Drug Administration for anything. Almost every human study of it was run in Russia, published in Russian-language journals, and used the nasal route at daily doses of 6 to 18 milligrams, which is twelve to seventy times the 250 to 500 microgram figure in this cheatsheet and delivered by a completely different route.

• Recovery after ischaemic stroke, the indication the largest human studies were designed around, where it was given intranasally alongside standard hospital care (Gusev 2018)
• Chronic cerebrovascular insufficiency, where a 187-patient Russian series reported stabilisation and fewer transient ischaemic attacks
• Optic nerve disease and optic neuropathy, where Russian ophthalmology groups added nasal Semax or endonasal electrophoresis to standard treatment
• Off-label use as a nootropic for focus, mental stamina and stress tolerance, which is not what any of the trials measured
• Claimed neuroprotection through raised BDNF, brain-derived neurotrophic factor, which rests mostly on rat hippocampus work and on one human plasma measurement in stroke patients
• A long tail of further Russian indications, including motor neuron disease, which illustrates how broadly the compound was trialled rather than how well it worked

Think of BDNF as fertiliser for brain cells: it does not plant anything new, it helps what is already there grow and repair. The animal work suggests Semax nudges the brain into producing more of that fertiliser and, after a blocked blood vessel, turns down the inflammatory alarm that does much of the secondary damage. The catch is the delivery. In the studies that showed anything, the fertiliser was sprayed directly up the nose in milligram amounts, whereas the off-label protocol injects a few hundred micrograms under the skin, and nobody has published what reaches the brain that way.

1. First 20 minIn a small placebo-controlled brain-imaging study of 24 healthy volunteers, a single 1 percent intranasal dose changed the resting-state default mode network within 5 to 20 minutes (Lebedeva 2018). Whether that corresponds to anything a person notices was not tested.
2. Days 1-10Russian stroke protocols ran 5-day or 10-day courses at 12 to 18 milligrams a day intranasally, and reported faster restoration of neurological function, mostly motor, over that window (Gusev 1997).
3. Day 10In 27 motor neuron disease patients the improvement in quality-of-life scores was largest at day 10 of a 10-day course, and it was emotional state and motivation that moved, not muscle function.
4. Weeks 1-6The 2018 stroke study used two 10-day courses separated by a 20-day gap and reported plasma BDNF that rose and stayed high across the study period, with Barthel index scores improving faster than in untreated controls (Gusev 2018).
5. Beyond 2 moNo human data beyond roughly two months was located, and no timeline of any kind exists for subcutaneous injection or for healthy people using it as a nootropic.

• The Russian trials consistently describe good tolerability; the 187-patient cerebrovascular series reported a minor percentage of side effects and good tolerance including in older patients, but did not tabulate what those side effects were
• None of the human studies located published a structured adverse-event table, so an absence of reported events here reflects the reporting standards of the journals as much as the behaviour of the compound
• The US Food and Drug Administration states that compounded drugs containing semax may pose risk for immunogenicity for certain routes of administration due to the potential for aggregation and peptide-related impurities, meaning an immune reaction raised against the peptide or against what is in the vial with it
• Injection-site reactions, and systemic effects of subcutaneous dosing generally, are not characterised anywhere in the published literature, because every human efficacy study located used the nasal route and the one study that injected Semax reported no adverse-event data
• Effects on the hypothalamic-pituitary-adrenal axis in humans were not measured in any study located, even though the molecule is a fragment analogue of a stress hormone
• Total published human exposure is in the hundreds of patients, concentrated in Russian hospital settings between 1997 and 2018, which is far too small to detect uncommon harms

• You are pregnant, trying to conceive, or breastfeeding; no human reproductive safety data was located, and the compound is derived from a hormone fragment
• You are treating an acute stroke or any acute neurological event outside a hospital; the trials added Semax to full inpatient care, they did not replace it, and self-treating a stroke wastes the window in which real treatment works
• You have a diagnosed psychiatric or seizure disorder under treatment, since no human study located enrolled those patients and no interaction data with psychiatric medication exists
• You have active nasal or sinus disease and intend to use the nasal route, which is the only route the human evidence covers
• You are a competitive athlete under the World Anti-Doping Agency code, because a compound derived from an ACTH fragment sits close enough to the section S2 language on corticotrophins that it is worth a written ruling before you use it
• You are under 18, or you are not working with a physician who knows you are taking it and can monitor you

• Assuming the injected protocol reproduces the trials. Every human efficacy study located used intranasal drops, and the single study that injected Semax measured brain connectivity without stating its route or dose. Subcutaneous injection of a reconstituted vial is a different route with a different absorption path, and no published pharmacokinetic or outcome data covers it.
• Ignoring the size of the dose gap. Russian stroke and neurology trials used 6,000 to 18,000 micrograms a day intranasally. The cheatsheet figure is 250 to 500 micrograms. Results obtained at one scale say very little about the other, in either direction.
• Reading the Russian registration as an approval you can rely on elsewhere. The compound is a registered medicine in Russia and an unapproved bulk substance in the United States, where the Food and Drug Administration has flagged immunogenicity and impurity concerns for compounded material.
• Mishandling the vial. Reconstitute with bacteriostatic water run slowly down the vial wall rather than tap or spring water, swirl instead of shaking, keep the lyophilised powder cold and dark, refrigerate after reconstitution, and discard on the timeline your pharmacist gives rather than stretching one vial for months.
• Stacking it with several other unapproved peptides at once, often alongside Selank. No interaction data exists for any of these combinations, and running them together makes any effect, good or bad, impossible to attribute.