Human growth hormone (HGH) has scientific validation for use in supporting convalescence, particularly in individuals experiencing severe catabolic states such as after major surgery, trauma, burns, or prolonged critical illness. HGH is an anabolic hormone that stimulates protein synthesis, increases lean body mass, and promotes tissue repair. Its use is based on the observation that endogenous growth hormone levels can become insufficient during periods of severe stress or extended illness, contributing to muscle wasting and delayed recovery.

Several clinical studies have demonstrated that recombinant human growth hormone administration can enhance protein synthesis, reduce nitrogen loss, and improve wound healing in patients recovering from major injuries or surgery. Randomized controlled trials in the 1990s showed that HGH could accelerate recovery in severely catabolic patients, especially when combined with nutritional support. However, subsequent large-scale studies in critically ill adults found increased mortality rates associated with high-dose HGH, leading to caution in its use outside of specific patient populations.

Currently, HGH is sometimes used in specific cases of prolonged convalescence where muscle wasting and impaired healing are profound and other treatments are ineffective. Its use is not routine due to potential side effects, including hyperglycemia, edema, and increased risk of certain complications. Nonetheless, the scientific rationale for its role in supporting recovery remains strong in selected clinical scenarios, and HGH is approved for such indications in some countries.