Dr. Pep

Peptides · GHRH analogue (GRF 1-29)

Sermorelin: what the studies show

Every line below comes from a study, label or regulator record, checked by two models, with the source linked. Information, not medical advice. For adults 18+.

What it is

  • Sermorelin is the first 29 amino acids of human growth-hormone-releasing hormone (GHRH), the brain signal that tells the pituitary gland to release growth hormone. It is written GHRH(1-29)-NH2 in the older papers. It makes the body release its own growth hormone rather than supplying growth hormone itself.[1][2]
  • It is not the same as other GHRH analogues. [Nle27]GHRH(1-29)-NH2 (a modified version), pegylated GHRH, tesamorelin and CJC-1295 are different molecules. Where a trial below used one of these, the text says so.[3][4]

Bottom line

  • Sermorelin clearly makes the pituitary release growth hormone in people, but the human studies are small and old, mostly from the 1990s. In children with growth hormone deficiency it grew them less than growth hormone itself. No modern trial tests it for ageing, body composition or sport.[1][5][6]

What the human studies found

  • Growth hormone release (RCT, 30 healthy men aged 19 to 43): an IV injection of GHRH(1-29)-NH2 as low as 0.25 µg/kg released growth hormone, and 1 to 2 µg/kg gave the largest peaks. Growth hormone stayed raised for about 3 hours. Nasal absorption was only 3 to 5%.[1]
  • Children with growth hormone deficiency (RCT, 60 children, 6 months): GHRH(1-29)-NH2 at 30 or 60 µg/kg/day grew children 9.2 and 9.3 cm per year, versus 14.6 cm per year on growth hormone 0.1 IU/kg/day. All children on the high dose and 19 of 20 on the low dose made antibodies to GHRH. The antibodies faded within 9 months of stopping, and there was no link between antibodies and growth. Three children had mild injection-site irritation.[5]
  • In a second RCT of 43 children with growth hormone deficiency, height velocity was lowest on low-dose GHRH(1-29)-NH2 and similar between the high-dose GHRH and growth hormone groups. Height gain relative to bone age rose only on growth hormone.[2]
  • Older adults, modified analogue ([Nle27]GHRH(1-29)-NH2, not sermorelin itself): in a single-blind placebo-controlled trial in 19 men and women aged 55 to 71, nightly injections of 10 µg/kg for 16 weeks raised nighttime growth hormone and increased IGF-I and IGFBP-3 within 2 weeks. In the same cohort immune function was also examined.[3][7]
  • Pegylated GHRH, a longer-lasting GHRH analogue and not sermorelin (RCT, 12 young men and 20 older adults): single doses of 0.25 to 4 mg raised growth hormone for up to 12 hours, and repeated dosing in older adults raised IGF-I. Some glucose tolerance impairment was seen in older adults after repeated dosing.[4]

Known risks and side effects

  • In the children's trials the only reported side effect was mild injection-site irritation in three children, and antibodies to GHRH formed in almost all treated children.[5]
  • In the 2024 FDA committee transcript for ipamorelin, an adverse-event report involved joint pain after an injectable product containing ipamorelin and sermorelin. FDA said such reports were limited by missing case detail and other medicines.[8]
  • Case report: a 62-year-old recreational bodybuilder who reported about 20 years of growth hormone, sermorelin and GHRP-6 use had a bone spur pressing on the gullet. The authors only raise the possibility that growth hormone axis stimulation contributed.[9]

Legal status

  • A 2024-12-10 FDA warning letter to Xcel Research LLC said 'Sermorelin' and other peptides sold on its website as 'for research use only' were unapproved new drugs.[10]
  • The records held contain no FDA label or approval history for sermorelin, so this card makes no statement about its past or current approval status.[10]

Sources

  1. [1] Pharmacokinetics of growth hormone-releasing hormone(1-29)-NH2 and stimulation of growth hormone secretion in healthy subjects after intravenous or intranasal administration.
  2. [2] Growth response to growth hormone-releasing hormone(1-29)-NH2 compared with growth hormone.
  3. [3] Endocrine and metabolic effects of long-term administration of [Nle27]growth hormone-releasing hormone-(1-29)-NH2 in age-advanced men and women.
  4. [4] Polyethylene glycol-conjugated growth hormone-releasing hormone is long acting and stimulates GH in healthy young and elderly subjects.
  5. [5] A comparative study of growth hormone (GH) and GH-releasing hormone(1-29)-NH2 for stimulation of growth in children with GH deficiency.
  6. [6] The emerging landscape of performance-enhancing peptides modulating GH-IGF1 axis: bridging the gap between clinical evidence and patient self-administration.
  7. [7] Effects of [norleucine27]growth hormone-releasing hormone (GHRH) (1-29)-NH2 administration on the immune system of aging men and women.
  8. [8] FDA: PCAC Topic 3 transcript, ipamorelin (2024-10-29)
  9. [9] Anterior cervical osteophyte-related dysphagia in a long-term growth hormone user: a case report.
  10. [10] FDA: Warning Letter, Xcel Research LLC (2024-12-10), retatrutide, semaglutide, cagrilintide, survodutide, mazdutide, sermorelin