The evidence position
FDA lists only “potential molecular targets of semax” (slide 18) and hedges the mechanism — “likely mediated by semax-induced increase in serotoninergic signaling.” (slide 19) FDA also states “the systemic exposures needed for a pharmacological effect are unknown.” (slide 18)
FDA characterises the efficacy evidence as “one small, uncontrolled, open label study” (slide 30) with “no blinding, no control group, small sample size.” (slide 29) Russian-language references “were not considered” because “the full references were not available in English” (slide 23), so part of the literature is inaccessible rather than absent.
FDA: “No published pharmacokinetic studies in humans.” (slide 36) FDA also records an adverse-event report that “resulted in hospitalization and persistence of symptoms for at least a year” (slide 33), and raises “concern about the risk of bleeding, particularly in certain populations.” (slide 36)
Not named on the WADA Prohibited List. Note that class S0 covers substances with no current approval for human therapeutic use, so absence from the list is not a clearance.
In July 2026 the US Food and Drug Administration reviewed Semax for the 503A Bulk Drug Substances list and proposed that it not be included. FDA briefing document, Pharmacy Compounding Advisory Committee, 23–24 July 2026.
The pathways it is reached for
BDNF — the growth factor that builds new synapses and neurons, the substrate of learning and mood.
The chemistry of wanting, not of liking. Dopamine sets how much effort a goal feels worth — which is why its loss reads as apathy long before it reads as sadness. More is not better: the same system that drives pursuit drives compulsion.
Serotonin — the neurotransmitter of mood and satiety, and the precursor the body converts to melatonin for sleep.
The receptor acetylcholine uses to sharpen signal against noise. It is the one the brain leans on to hold attention on a thing, and it thins with age.
Adrenocorticotropic hormone — the pituitary messenger that carries the stress signal from brain to adrenal gland.
The whole apparatus of thinking: taking information in, holding it, working with it, and getting it back out. It is not one faculty but at least six, and they decline at different rates and respond to different things — which is why they are split.
One of the six dsm-5 cognitive domains: taking new information in and getting it back out later. Separated from attention deliberately — cholinergic imaging in Parkinson's found denervation tracked attention, executive and visuospatial function but not memory.
A subdomain of executive function: keeping information available for seconds while you use it. Governed by an inverted-U — in the prefrontal cortex, either too little or too much dopamine signaling impairs it.
A subdomain of executive function: changing rule, strategy or task set when conditions change. Distinct from inhibition, though both live in the frontal lobes.
What we carry on those pathways
Shares 6 of these pathways: BDNF, Dopamine, Serotonin, Cognition, Working Memory, Cognitive Flexibility.
Shares 4 of these pathways: BDNF, Dopamine, Serotonin, ACTH.
Shares 4 of these pathways: BDNF, Dopamine, Serotonin, Cognition.
Shares 3 of these pathways: BDNF, Serotonin, Nicotinic Acetylcholine Receptor.
BDNF → Mood (Positive Affect). “A single bilateral infusion of BDNF into the dentate gyrus of hippocampus produced an antidepressant effect in both the LH and FST that was comparable in magnitude with repeated systemic administration of a chemical antidepressant.” — Brain-Derived Neurotrophic Factor Produces Antidepressant Effects in Behavioral Models of Depression. Journal of Neuroscience, 2002, vol 22(8), 3251-3261. doi:10.1523/JNEUROSCI.22-08-03251.2002
BDNF → Neurogenesis. “Acute BDNF infusion induced long-term potentiation (LTP) of medial perforant path-evoked synaptic transmission and, concomitantly, enhanced hippocampal neurogenesis bilaterally, reflected by increased dentate gyrus BrdU+ cell numbers.” — BDNF-induced LTP is associated with rapid Arc/Arg3.1-dependent enhancement in adult hippocampal neurogenesis. Scientific Reports, 2016, 6:21222. doi:10.1038/srep21222
Dopamine → Complex Attention. “The results provide apparently the first demonstration of enhanced cognitive function after local administration of a D1 receptor agonist to the mPFC and suggest dissociable roles of D1 and D2 DA receptors of the mPFC in modulating attentional function.” — Enhanced and Impaired Attentional Performance After Infusion of D1 Dopaminergic Receptor Agents into Rat Prefrontal Cortex. Journal of Neuroscience, 2000, 20(3):1208-1215. doi:10.1523/JNEUROSCI.20-03-01208.2000
Dopamine → Melatonin. “Through α1B-D4 and β1-D4 receptor heteromers dopamine inhibits adrenergic receptor signaling and blocks the synthesis of melatonin induced by adrenergic receptor ligands.” — Circadian-Related Heteromerization of Adrenergic and Dopamine D4 Receptors Modulates Melatonin Synthesis and Release in the Pineal Gland. PLoS Biology, 2012, volume 10, e1001347. doi:10.1371/journal.pbio.1001347
Dopamine → Mood (Positive Affect). “Boosting dopamine also increased happiness resulting from some rewards.” — Dopaminergic Modulation of Decision Making and Subjective Well-Being. Journal of Neuroscience, 2015, 35(27), 9811-9822. doi:10.1523/JNEUROSCI.0702-15.2015 | PMC4495239
Serotonin → Hot Flushes & Night Sweats. “Most studies have indicated the efficacy and safety of some antidepressants, such as SSRIs and SNRIs, in decreasing the frequency and severity of HF.” — The Efficacy and Safety of Selective Serotonin Reuptake Inhibitors and Serotonin-Norepinephrine Reuptake Inhibitors in the Treatment of Menopausal Hot Flashes: A Systematic Review of Clinical Trials. Iranian Journal of Medical Sciences, 2022, vol 47, no 3, pages 173-193. doi:10.30476/ijms.2020.87687.1817
What a grade means here
Every ingredient row on our formula pages carries one of these grades, fixed by a standard set before the evidence was gathered. The grades below are reproduced from those pages.
Randomized human trials, or a meta-analysis of them, measuring this pathway's own endpoint — either a clinical outcome or a validated biomarker.
Human data, or animal evidence replicated by an independent laboratory. It opens a pathway only alongside an independent corroborating driver.
Mechanistic, cell or animal evidence. No single preclinical driver opens a pathway on its own.
What this page does not claim
Sharing a pathway is not the same as sharing an effect. Nothing here says a botanical formula does what Semax does, and nothing here recommends Semax. The pathways above are named because that is what the published work on Semax points at; the formulas below are listed because our own map records graded, published evidence on those same pathways. Read both columns and judge them yourself — every figure on our side carries its grade and its source.