# Tesamorelin Dosage in the Research: Doses, Route, and Side Effects | RX Tesa > Tesamorelin dosage as studied: 2 mg subcutaneously once daily in the pivotal trials, with 1 mg/day arms in cognition and diabetes studies. Route, half-life context, and side effects from the literature. What was administered, to whom, by which route — a research-context register, not a dosing instruction. ## The short version This page reports the tesamorelin dosage used in published studies — it is not a how-to. In the major trials, researchers gave 2 mg as a once-daily injection under the skin of the belly; a few studies tested a lower 1 mg dose. The peptide clears the blood within about half an hour, but its effect lasts all day, which is why it was given once daily. Because research-grade tesamorelin is supplied for laboratory work and is not the approved finished medicine, nothing here is a recommendation to take it. Everything below is framed as "studied at X in [population]." ## Doses studied per day in the trials The tesamorelin dosage per day that anchors the literature is 2 mg subcutaneously once daily — the dose used in both pivotal Phase 3 trials and the regimen approved for HIV-associated lipodystrophy [1][2][3]. A 1 mg/day dose was studied in a cognition trial in older adults and as a lower arm in a type-2-diabetes safety study. The once-daily 2 mg paradigm is by far the most extensively characterized. These are descriptions of what was administered in trials, not instructions. In the pivotal 26-week trial, 2 mg/day produced a 15.2% visceral-fat reduction in 412 HIV patients [1]; in the 52-week program the same daily dose sustained an ~18% reduction [2]. A pooled analysis across two Phase 3 trials (543 on tesamorelin) tied 2 mg/day to a 3.9-fold greater chance of dropping visceral fat below 140 cm2 [13]. The consistency of the 2 mg figure across studies is itself informative: trials run by different groups, in different HIV cohorts, over 26 and 52 weeks, converged on the same daily amount and produced concordant visceral-fat effects [1][2][3]. The 1 mg arms were exploratory, used to probe whether a lower amount preserved the signal in non-fat-loss contexts such as cognition; the visceral-fat program never moved off 2 mg. None of this should be read as a personal dosing target — research-grade material lacks the potency verification of the approved product, and the studies measured a specific population, not a general user. ## Route studied: subcutaneous injection The only route studied in the clinical trials and the only approved route for the tesamorelin injection is subcutaneous administration into the abdomen [1][3]. The compound is supplied as a lyophilized powder requiring reconstitution; the approved-product label specifies refrigerated storage and use of the reconstituted solution within a defined window. A non-clinical study did explore pulmonary delivery: intratracheal dry-powder insufflation in beagle dogs achieved 41% bioavailability relative to subcutaneous injection (13% absolute), with a comparable terminal half-life (intratracheal 39 min versus subcutaneous 26 min) and a longer mean residence time (74 versus 52 min) [9]. That inhaled route was a research finding only and never became the marketed product. ## Half-life context for the once-daily schedule The once-daily schedule rides on a pharmacokinetic mismatch covered in full on the [half-life and pharmacokinetics](/pharmacokinetics) page. Briefly: plasma exposure is short — a non-clinical study reported a ~21-45 minute elimination half-life in dogs [8], and secondary human sources describe ~26-38 minutes — with apparent clearance near 1,060 L/h [7]. The downstream IGF-1 elevation nonetheless persists across the 24-hour interval, which is the pharmacologic basis for once-daily dosing despite rapid clearance [7][4]. This matters for interpreting the dosing studies. Because the parent peptide is gone within the hour but the IGF-1 signal lasts the day [4], the trials did not need to dose more than once daily to keep the effect running, and the population pharmacokinetic model found no demographic covariates that would call for adjusting the amount by age, sex, or body size [7]. The reconstituted-powder formulation and the refrigerated storage window are practical handling details of the approved product, not pharmacology — but they are part of why the studied regimen is a single daily subcutaneous injection rather than anything more elaborate. ## Side effects and contraindications in the literature On tesamorelin side effects, the trial literature reports injection-site reactions and growth-hormone-class effects. The NIH LiverTox monograph rates tesamorelin unlikely to cause clinically apparent liver injury — a likelihood score of E — noting no reported attributable liver-injury cases and no de novo serum-enzyme elevations in trials [5]. Fluid-related effects are a recognized growth-hormone-class consideration and are among those monitored. The research literature flags active malignancy as a labeled contraindication and notes growth-factor (IGF-1) concerns, since GH-axis stimulation raises a growth factor. Over 52 weeks the trials showed no excess malignancy signal, but long-term oncologic-safety data are limited [2]. Glucose perturbation can be modest: in 13 healthy men neither fasting glucose (P=0.93) nor insulin-stimulated glucose uptake (P=0.61) changed significantly [4], and a dedicated type-2-diabetes trial found no significant HbA1c change — though monitoring is described for individuals with dysglycemia. Tesamorelin is a prescription drug studied for a specific HIV indication, not a general-use product, and it is prohibited in sport under WADA category S2. --- A shadowless data sheet of the tesamorelin record — the GHRH-receptor cascade and the visceral-fat numbers logged to source, the FDA approval marked exactly where it stops and the off-label boundary left in plain view; no clinic behind the grid and nothing here dispensed or sold.