Somatropin

Recombinant production introduces the human growth-hormone gene into cells that manufacture the 191-amino-acid protein. Somatropin brands include Genotropin, Norditropin, Omnitrope and Zomacton. Nutropin left the US market at the end of 2024, while Humatrope is being withdrawn at the end of 2026. Longer-acting engineered medicines such as lonapegsomatropin and somatrogon are separate molecules rather than ordinary somatropin.

Early growth-hormone treatment depended on hormone extracted from human cadaver pituitary glands, with a limited supply. That program ended in 1985 after contaminated material was linked to Creutzfeldt–Jakob disease, a fatal prion-related brain illness. Recombinant manufacture subsequently replaced the cadaver source and removed that source-specific transmission risk.

Growth-hormone receptors throughout the body respond to somatropin. Signaling increases IGF-1 production in the liver and other tissues. Together, GH and IGF-1 promote growth-plate bone growth, protein synthesis and fat breakdown, while also affecting carbohydrate handling.

For children with deficiency and certain growth disorders, treatment can improve growth velocity and adult height. In deficient adults, body-composition and metabolic measures can improve. Standard somatropin is cleared rapidly, so daily injections are typical; clinicians individualize the amount using growth response and IGF-1 measurements.

Multiple recombinant human growth-hormone products have FDA approval. Humatrope was approved in 1987, and other brands followed. Each product has its own approved indications, so approval of somatropin does not make every brand appropriate for every growth or wasting condition.

Product-specific uses include growth-hormone deficiency in children and adults and selected causes of short stature: Turner syndrome, Prader–Willi syndrome, chronic kidney disease, Noonan syndrome, SHOX deficiency, birth small for gestational age and idiopathic short stature. Some formulations also have approval for HIV-associated wasting. Eligibility and indications must be matched to the particular product.

Common adverse effects include injection reactions, aching muscles or joints, fluid-retention swelling and headache. GH can reduce insulin sensitivity and increase blood glucose. Use during acute critical illness carries a particular warning because trials found increased mortality.

Breathing requires assessment before and during treatment in Prader–Willi syndrome: sudden deaths have been reported in patients with severe obesity or respiratory problems. Other important risks include intracranial hypertension, slipped capital femoral epiphysis, progression of scoliosis in children, growth of existing tumors, pancreatitis and serious allergic reactions.