GHRP-2, a laboratory-made protein fragment that copies the hunger hormone ghrelin, triggers bursts of the body's own growth hormone and draws interest for muscle and healthy aging. Its one approved use, a single-dose test for growth hormone deficiency in Japan, is well supported. It raises growth hormone and hunger, but no study has shown better muscle function, body composition, sleep or lifespan in adults; longer-term concerns rest on indirect evidence. (Full Review)
| Marker | Target | Why |
|---|---|---|
| IGF-1 | Within the age-adjusted reference range, not above its upper limit | Shows effect and excess |
| Fasting glucose | 70–99 mg/dL | Safety check; rise changes use |
| HbA1c | 4.0–5.6% | Safety check; rise changes use |
| Prolactin | Men about 2–18 ng/mL; non-pregnant women about 2–29 ng/mL | Safety check; persistent rise changes use |
| Morning cortisol | About 5–25 µg/dL at 8 a.m. | Safety check; persistent rise changes use |
| ALT | About 7–56 U/L | Safety check; labeled liver-enzyme rise |
| White blood cell count | About 4.5–11.0 × 10⁹/L | Safety check; labeled rise |
| Pregnancy test | Negative | Pregnancy is a contraindication |
Cadence: Baseline panel, including a pregnancy test for women who could become pregnant, before starting; IGF-1 and fasting glucose at 4–6 weeks, then every 3 months while in use; HbA1c every 3 months; prolactin, morning cortisol, ALT and white blood cell count at 3 months, then every 6 months; abnormal hormone results repeated after stopping.