# Semax Dosage in the Research Literature: Routes, Protocols, and Stability > Semax dosage as documented in the published research literature: intranasal vs subcutaneous routes, Russian clinical protocols, cycling studies, storage stability, and pharmacokinetics. ## Semax Dosage in the Research Literature Semax dosage documentation in the published literature spans rodent preclinical work, in vitro assays, and a limited body of Russian clinical protocols. This page indexes what doses were administered, by which route, in which species or study type. It does not constitute dosage guidance for any human use. Research dose ranges: 30-250 µg/kg intranasal in behavioral and neurotrophin studies; [1][2][3] 100 µg/kg intraperitoneal in rat ischemia models; [4][5] 50 µg/kg intranasal in developmental and stress models. [12][13] Russian clinical stroke protocols describe 1-2 mg/day as a 1% intranasal spray in 10-day courses. [15] ## Semax Nasal Spray: Administration in Research Models Semax nasal spray is the primary administration route studied in Eastern European clinical and pre-clinical trials, enabling direct CNS access via the olfactory mucosa. [9] Shevchenko et al. (2006) measured the pharmacokinetics of intranasal Semax in rats: approximately 80% of recovered radioactivity in brain at 2 minutes post-dose represented intact Semax peptide. [9] This 2-minute brain-entry time is consistent with olfactory transport pharmacokinetics, bypassing the blood-brain barrier. In Russian clinical stroke protocols, 1% nasal spray preparations at approximately 1-2 mg/day in 10-day courses have been described in observational reports. [15] ## Semax half-life and duration of action Parent peptide half-life is approximately 2-5 minutes in plasma. Active metabolites extend neurological effects to several hours in rodent models. [9] The primary metabolite is Pro-Gly-Pro (PGP), which retains independent neurotrophin-activating properties. BDNF transcription, once initiated via cAMP/CREB signaling, continues after peptide clearance — producing a duration of biological effect substantially longer than the parent compound's plasma half-life. ## Cycling protocols in Semax research Russian clinical protocols typically describe 10-14 day courses with off periods. [15] The pharmacological rationale for cycling is not fully characterized in the Western literature. MC4R downregulation kinetics under sustained Semax exposure have not been quantified in any published study identified in this review. ## Semax storage and stability Peptide stability studies recommend refrigerated storage at 2-8°C for aqueous solutions; lyophilized powder is stable at room temperature for shorter periods. [17][18] Light exposure and repeated freeze-thaw cycles degrade peptide activity. N-acetylation at the N-terminus reduces susceptibility to aminopeptidase cleavage. [18] C-terminal amidation (as in N-Acetyl Semax Amidate) additionally blocks carboxypeptidase cleavage of the C-terminal Pro residue. ## Onset of Semax effects in research models CNS activity markers appear within 15-30 minutes of intranasal dosing in rat models, consistent with olfactory transport pharmacokinetics. [9] In the Shadrina et al. (2001) glial cell culture study, 8-fold BDNF mRNA increase was measured within 30 minutes. [7] The Shadrina et al. (2010) in vivo study noted region-specific temporal patterns: initial decreases at 20 minutes in hippocampus and retina, followed by increases in frontal cortex and retinal recovery at 90 minutes. [8] ## References [1] Dolotov OV, et al. Semax increases BDNF in rat basal forebrain. Journal of Neurochemistry. 2006. — https://pubmed.ncbi.nlm.nih.gov/16635254/ [2] Dolotov OV, et al. Semax regulates BDNF and trkB in rat hippocampus. Brain Research. 2006. — https://pubmed.ncbi.nlm.nih.gov/16996037/ [3] Inozemtseva LS, et al. Semax activates dopaminergic and serotoninergic systems. Neuroscience Letters. 2006. — https://pubmed.ncbi.nlm.nih.gov/16362768/ [4] Sudarkina OY, et al. Semax in rat Cerebral Ischemia-Reperfusion. IJMS. 2021. — https://pubmed.ncbi.nlm.nih.gov/34201112/ [5] Medvedeva EV, et al. Semax affects gene expression in focal ischemia. BMC Genomics. 2014. — https://pmc.ncbi.nlm.nih.gov/articles/PMC3987924/ [7] Shadrina MI, et al. Rapid induction of neurotrophin mRNAs by Semax in glial cultures. 2001. — https://pubmed.ncbi.nlm.nih.gov/11457573/ [8] Shadrina M, et al. NGF and BDNF gene expression dynamics under Semax action. 2010. — https://pubmed.ncbi.nlm.nih.gov/19662538/ [9] Shevchenko KV, et al. Kinetics of Semax penetration into rat brain. 2006. — https://pubmed.ncbi.nlm.nih.gov/16523722/ [12] Volodina MA, et al. Correction of Neonatal Isolation Effects Using Semax. Acta Naturae. 2012. — https://pmc.ncbi.nlm.nih.gov/articles/PMC3372995/ [13] Volodina MA, et al. Semax attenuates neonatal maternal deprivation effects. 2012. — https://pubmed.ncbi.nlm.nih.gov/22803132/ [15] Kurysheva NI, et al. Semax in treatment of glaucomatous optic neuropathy. 2001. — https://pubmed.ncbi.nlm.nih.gov/11569188/ [17] Shevchenko KV, et al. Proteolysis of Semax analogues by carboxypeptidases. Doklady Biological Sciences. 2013. — https://pubmed.ncbi.nlm.nih.gov/23821053/ [18] Shevchenko KV, et al. Stability of Semax acetyl to proteolysis in biological media. 2013. — https://pubmed.ncbi.nlm.nih.gov/23652441/ [19] Volodina MA, et al. Semax effect on intracellular calcium dynamics. 2025. — https://link.springer.com/article/10.1007/s10517-025-06501-z --- A kiln-fired digest of the peer-reviewed Semax record — heptapeptide research indexed from the literature, no clinic behind the shelf.