Sermorelin

Sermorelin is a synthetic peptide that mimics Growth Hormone-Releasing Hormone (GHRH). It stimulates the pituitary gland to produce and release more natural human growth hormone (HGH). It was originally approved by the FDA for the treatment of growth hormone deficiency in children but is now primarily used off-label by adults in functional and regenerative medicine to address age-related hormone decline.

It is composed of 29 amino acids and is believed to increase growth hormone production in the body. This may support improvements in lean muscle mass, energy levels, and metabolism. It is also thought to promote better sleep and overall vitality.

Studies of Sermorelin show that it increases growth hormone (GH) and insulin‑like growth factor 1 (IGF‑1) levels in humans. For example, a study found that 16 weeks of administration significantly elevated mean GH levels and IGF‑1 with resulting increased lean body mass in men ¹. In addition, animal and human evidence suggest that by boosting endogenous GH release, Sermorelin may support tissue repair and regeneration ².

Beyond hormone increases, the research suggests Sermorelin may improve body composition, especially by increasing lean mass in men and enhancing skin thickness in both genders. Some reports also indicate potential benefits for metabolism and sleep quality given GH’s role in these systems ^{3, 4}. In sum, Sermorelin’s main benefits appear to stem from its capacity to stimulate natural GH and IGF‑1 production, which in turn may favour improved body composition, tissue recovery, metabolism, and sleep.

Clinical trials in children noted that the most common adverse events were transient facial flushing and pain at the injection site when using once‑daily subcutaneous administration ⁵. Beyond these more minor side effects, studies and reviews suggest potential risks associated with growth‑hormone‑axis stimulation that apply to sermorelin because of its mechanism. For example, long‑term administration of GHRH analogues has been linked to issues such as water and salt retention (edema), impaired glucose tolerance and carpal tunnel syndrome in broader GH therapy contexts ⁶. One review also noted concerns about the possibility of growth‑hormone‑mediated effects such as promoting cell proliferation (and thus potentially exacerbating hormonally‐sensitive tumours), although specific causal links with sermorelin remain speculative ⁷.

Sermorelin is a synthetic analogue of the first 29 amino acids of Growth hormone‑releasing hormone (GHRH) that acts by binding to the GHRH receptor on somatotroph cells in the anterior pituitary gland. This receptor binding triggers G‑protein‑coupled activation of adenylyl cyclase, raising cyclic AMP and stimulating transcription of growth hormone (GH) mRNA and subsequent GH synthesis and pulsatile secretion. Because this mechanism leverages the body’s own GH‑axis, the released GH is subject to endogenous regulatory feedback (notably via Somatostatin) and exhibits more physiologic pulsatility rather than continuous levels seen with exogenous GH administration ^{8, 9, 10}.

Sermorelin (brand name Geref, sermorelin acetate) was an FDA-approved product (approved 09/26/1997) but the manufacturer discontinued commercial production and the NDA was withdrawn/marked discontinued. The FDA has treated the product as discontinued (not withdrawn for safety/effectiveness), and sermorelin is not generally available as an FDA-marketed product today. However, sermorelin is commonly supplied to patients today via compounding pharmacies by prescription (i.e., it is not currently available as an active FDA-approved commercial product) ¹⁰. In sports, growth hormone–releasing hormones (GHRHs) and their analogues (which include sermorelin/GHRH(1-29) analogues) are listed by WADA as prohibited (growth hormone axis / GHRH/releasing factors are banned). National anti-doping organizations (e.g., USADA) likewise list sermorelin as prohibited for athletes ¹¹.