# Epitalon Dosing in Published Studies: Routes, Ranges, and Pharmacokinetic Notes > Epitalon dosing in the published research literature: rodent microgram-per-mouse subcutaneous protocols, Russian human-cohort intramuscular courses, parabulbar ophthalmic series, and the unresolved pharmacokinetic record. A reading of routes, doses, and durations across rodent cancer models, Russian elderly cohorts, and small ophthalmic series — described as published research dosing, not as clinical recommendation. ## The dosing summary in one paragraph Epitalon dosing in the published peer-reviewed literature falls into three buckets. Rodent geroprotection studies dominate: monthly 5-day subcutaneous courses at 0.1 to 1.0 microgram per mouse (roughly 4 to 40 microgram/kg in a 25 g mouse), repeated across years of life [4][6][7][9]. Russian human-cohort reports describe short intramuscular courses of the parent pineal extract Epithalamin in elderly subjects — typically on the order of 10 mg per injection, 5 injections per course, repeated periodically — with measured endpoints around melatonin secretion [11]. A small ophthalmic series in retinitis pigmentosa patients used parabulbar Epitalon at 5 micrograms per eye for 10 consecutive days [13]. All described below as published study dosing, not as personal clinical recommendation. ## Doses used in published studies Rodent studies overwhelmingly use microgram-per-mouse subcutaneous dosing on monthly cycles. Anisimov 2002 in *International Journal of Cancer*: 1 microgram per mouse subcutaneous, 5 consecutive days every month, in female HER-2/neu transgenic mice [4]. Anisimov 2003 in *Biogerontology*: 1 microgram per mouse subcutaneous, 5 consecutive days every month, from age 3 months, in female SHR mice (cumulative monthly exposure ~30-40 microgram/kg) [6]. Kossoy 2006 in *In Vivo*: 0.1 microgram per mouse subcutaneous, 5 days per week for 6.5 months, in 1-year-old female C3H/He mice [7]. Vinogradova 2007 in *Bulletin of Experimental Biology and Medicine*: 0.1 microgram per rat subcutaneous, 5 days per month, in female outbred LIO rats [10]. Russian human-cohort intramuscular courses of Epithalamin typically reported around 10 mg per injection with 5 injections per course [11]. Parabulbar ophthalmic series: 5 micrograms per eye, 10 consecutive days [13]. ## Routes of administration in published work Routes studied in the peer-reviewed literature include subcutaneous (the dominant rodent route) [4][6][7][8], intramuscular (the dominant human-cohort route for Epithalamin courses) [11], intraperitoneal (some rat protocols), parabulbar/peri-ocular (the retinitis pigmentosa series at 5 microgram per eye for 10 days) [13], and intranasal (reported in some Russian work). In vitro cell-culture exposure is used in all the mechanism studies [1][2][3]. Oral bioavailability of the intact tetrapeptide is expected to be poor and has not been formally validated in the peer-reviewed Western record [15]. ## Epitalon half-life and pharmacokinetics Validated plasma half-life data for the intact AEDG tetrapeptide is sparse in the PubMed-indexed literature. As a short, unmodified linear peptide, rapid serum proteolysis is expected — clearance on the order of minutes to low single-digit hours rather than days [15]. The 2025 Araj review in *International Journal of Molecular Sciences* identifies validated pharmacokinetic characterisation as one of the primary outstanding research gaps for the compound: 'formal physicochemical characterisation and modern human safety/toxicology data remain limited' [15]. No human PK study with formal AUC, Cmax, or half-life values for the synthetic tetrapeptide is published in the indexed Western literature as of 2026. The most-honest reading is that the molecule's PK is plausible — short linear peptide, parenteral routes, rapid proteolysis — but unvalidated. ## How is Epitalon administered in studies? In published studies, subcutaneous and intramuscular injection are the most commonly reported routes [4][6][7][8][11]. Intranasal delivery has been examined in some Russian-program work. Parabulbar (peri-ocular) injection was used in the retinitis pigmentosa series [13]. In vitro cell-culture exposure is the standard route in mechanism work [1][2][3]. Oral bioavailability of the intact tetrapeptide is expected to be poor and has not been formally validated; no oral-route human dosing study appears in the PubMed-indexed Western record [15]. ## Stability and formulation notes Epitalon is a short linear tetrapeptide without disulfide bridges or post-translational modifications. Most published research work uses parenteral delivery (subcutaneous, intramuscular, intraperitoneal, parabulbar) precisely because oral bioavailability of intact short peptides is generally low and is not formally validated for this compound [15]. The TFA salt (CAS 307297-39-8) is the form commonly used in research synthesis [15]. Storage and reconstitution practices in the published rodent work typically use lyophilised peptide reconstituted in physiological saline before subcutaneous injection. ## Duration and cycle structures in the rodent work Rodent geroprotection studies use long-duration cyclic dosing. The canonical Khavinson-program protocol — monthly 5-day courses, repeated across years of an animal's life — appears in the Anisimov 2002 HER-2/neu mammary-tumor study [4], the Anisimov 2003 SHR mouse reproductive-ageing study [6], the Vinogradova 2007 illumination-regime study [10]. The Kossoy 2006 study used a more frequent schedule — 5 days per week for 6.5 months — and reported reduced malignant-tumor incidence and metastasis prevention without observable toxicity [7]. Across these protocols, cumulative annual exposure ranges from roughly 60 micrograms per mouse per year (monthly 5-day at 1 microgram/mouse) to roughly 130 micrograms per mouse over the 6.5-month Kossoy protocol [4][7]. Mean lifespan was not increased in the SHR mouse cohort even at the multi-year exposure [6]. --- A textile-layered editorial digest of the Khavinson pineal tetrapeptide literature — Epitalon and Epithalon read as one molecule, two spellings, and twenty-five years of mostly-Russian record, with the Western trial gap named.