Tesamorelin is a synthetic peptide analogous to growth hormone-releasing hormone (GHRH) that stimulates natural growth hormone (GH) release, primarily used to reduce visceral fat in HIV-associated lipodystrophy and researched for body composition, recovery, and metabolic health.
What is Tesamorelin?
Tesamorelin (also known as Egrifta or Tesamorelin acetate) is a synthetic therapeutic peptide composed of 44 amino acids. It is a modified analog of endogenous growth hormone-releasing hormone (GHRH), designed to be more stable and longer-acting than natural GHRH.
Unlike direct growth hormone injections, tesamorelin works by stimulating the pituitary gland to release the body’s own GH, which then increases insulin-like growth factor 1 (IGF-1) levels.
Mechanism of Action
Tesamorelin binds to GHRH receptors in the anterior pituitary, triggering somatotrophic cells to secrete growth hormone.
GH subsequently influences multiple tissues:
Adipocytes (fat cells) – promotes lipolysis and reduces visceral fat.
Myocytes (muscle cells) – supports muscle growth and maintenance.
Hepatocytes (liver cells) – induces IGF-1 production.
Other organs – influences bone density and tissue repair.
Because tesamorelin stimulates GH release naturally, homeostatic feedback mechanisms help maintain appropriate hormone levels and reduce the risk of GH overproduction.
Clinical and Therapeutic Uses
The main FDA-approved use of tesamorelin is for HIV-associated lipodystrophy, a condition characterized by abnormal visceral fat accumulation.
Clinical trials have shown it can reduce visceral adipose tissue 15–20% over several months, while improving metabolic markers such as triglycerides and cholesterol.
Additional potential and researched applications include:
Body composition enhancement – reducing visceral fat while preserving lean muscle mass.
Recovery and tissue repair – promotes collagen turnover and wound healing due to GH and IGF-1 elevation.
Cognitive function – may support memory, executive function, and age-related cognitive decline.
Metabolic regulation – improves insulin sensitivity and lipid profiles.
Administration and Dosage
Tesamorelin is administered via subcutaneous injection, typically below the belly button. It comes as a lyophilized powder that requires reconstitution with sterile or bacteriostatic water before injection.
FDA-approved dosing for HIV lipodystrophy: 2 mg subcutaneously once daily, 5 days per week, preferably before bedtime.
Bodybuilding or fat loss (research/experimental doses): typically range from 1–2 mg daily, injected 60–90 minutes before a meal. Cycles often last 8–12 weeks, with rotation of injection sites to reduce irritation.
Benefits Observed in Research
Studies and anecdotal reports highlight benefits such as:
Targeted reduction of visceral fat, improving waist-to-hip ratio and body composition.
Preservation and potential increase of lean muscle during fat loss phases.
Enhanced recovery from muscle or connective tissue injuries.
Improved metabolic markers including triglycerides, cholesterol, and insulin sensitivity.
Cognitive support in older adults or those with mild cognitive impairment.
Potential Side Effects
Tesamorelin is generally well tolerated, but some mild and transient side effects may occur:
Injection site reactions: redness, swelling, itching.
Muscular/joint aches, mild fluid retention.
Gastrointestinal symptoms such as nausea or diarrhea.
In rare cases, blood sugar changes or increased insulin resistance may occur; monitoring is recommended, especially for prediabetic or diabetic individuals.
It is contraindicated in individuals with active cancer, pituitary tumors, or during pregnancy/breastfeeding.
***DISCLAIMER*** Prescription medications require evaluation by a licensed provider. Individual results may vary.