# Thymulin Dosage in Research: Doses, Routes, and Half-Life > Thymulin dosage as reported in studies: the nanogram-to-microgram amounts administered in animal models, the routes researchers used, the half-life question, and why there is no human protocol. Cited, not prescriptive. There is no established human dose. Here are the amounts and routes researchers actually used in animals and assays — reported as study facts, never as guidance. ## The short version Quick and clear: there is no established human thymulin dosage, and nothing on this page tells anyone to take anything. What exists is a research record — the specific amounts scientists gave to animals, and the routes they used, in published studies. Doses run from nanograms to a few micrograms per animal (a nanogram is a billionth of a gram) [13]. Routes range from injection to inhaled gene therapy [4][7]. We report each one as a study finding, attached to its species and citation. That is the only honest way to talk about thymulin dosing. ## Thymulin peptide dosage in the research literature Thymulin peptide dosage in the literature is small — fitting for a potent endogenous hormone. In rodent neuroinflammation and analgesia work, doses sat in the 0.1-1 microg intracerebroventricular and 1-1000 ng intraperitoneal range [4]. In the rat pulmonary-hypertension model, thymulin was given at roughly 100 ng/kg/day subcutaneous [8]. In chickens, antiviral NK-cell effects appeared at 10 ng/100 g and 50 ng/100 g body weight [13]. Protective and immune models used somewhat higher amounts: 50 microg/head intraperitoneal pre-LPS for pancreatic protection in mice [11], 10-50 microg subcutaneous for protection against virus-induced diabetes and myocarditis in mice [12], and 3-100 microg/day subcutaneous for radioprotection in irradiated mice [14]. Every figure is what a study administered in a named species — not a human dose, not a recommendation. ## How thymulin is administered in research Researchers reached thymulin's targets through many routes, picked to fit the model. The studied routes include intraperitoneal [11], subcutaneous [8][12][14], intracerebroventricular for CNS work [4], intratracheal for inhaled gene therapy [7], intramuscular for gene-therapy vectors [5], a topical route in a small zinc-thymulin cosmetic pilot, and plain in-vitro addition for cell assays [13]. The gene-therapy routes deserve a flag: there, the thymulin gene is delivered as a plasmid or viral vector, so the peptide is expressed by the body rather than injected [5][7]. These describe laboratory studies and delivery strategies — not a human administration protocol. ## Thymulin half-life As a small peptide, native thymulin has a short circulating half-life — it clears quickly. But a precise human pharmacokinetic half-life is not well established in the public literature [4]. That gap is part of why gene-therapy approaches were developed: by making the body express thymulin continuously, researchers sidestep the rapid clearance of an injected peptide and sustain circulating levels [5][7]. So the practical answer is: short for the native peptide, not precisely characterized in humans, and engineered around in the gene-therapy work. ## What doses of thymulin were used in animal studies? Concrete examples from the record: 0.1-1 microg intracerebroventricular and 1-1000 ng intraperitoneal in rodent neuroinflammation and analgesia models [4]; about 100 ng/kg/day subcutaneous in a rat pulmonary-hypertension model [8]; 10 and 50 ng/100 g body weight in chickens [13]; 50 microg/head intraperitoneal in a mouse pancreatic-protection model [11]; 3-100 microg/day subcutaneous for radioprotection in mice [14]. All reported as study findings only. ## Is there a thymulin supplement? No. Thymulin is not a dietary supplement — it is a research peptide, and it is not FDA-approved [4]. You will not find a legitimate thymulin supplement on a shelf the way you find a vitamin. Because thymulin's activity depends entirely on zinc, much of the human-relevant research instead studies zinc status as a determinant of how much active thymulin is circulating [2][3]. If a product markets itself as a thymulin supplement, treat that framing skeptically: the science here is preclinical and the compound is a research peptide, not a consumer supplement [4]. ## Thymulin peptide side effects: what the limited data show CAREFUL — the side-effect picture is thin, and that thinness is the finding. Human safety data on native thymulin are sparse and dated, and several human studies used a synthetic analog (nonathymulin) rather than native thymulin [4]. A small topical zinc-thymulin pilot was reported as well-tolerated, but it was a small, low-tier study [4]. There is no comprehensive human side-effect profile for thymulin, and no standardized human dosing in the public literature [4]. Anyone reading dose figures here should read them as what they are: animal-study facts, not a safety clearance for human use. --- A high-energy reading of the thymulin record drawn panel by panel — the zinc power-up that switches the nonapeptide on, the T-cell and lung findings, and the missing human trials all inked from the published studies; no clinic behind the page and nothing here dosed, dispensed, or sold.