Somatropin (HGH)
aka Recombinant human growth hormone, rHGH
A lab-made copy of human growth hormone — exactly the same molecule your pituitary makes.
Technically · Recombinant growth hormone
In one sentence
The full growth hormone molecule itself — FDA-approved for kids and adults with real GH deficiency, abused for anti-aging.
— Same hormone your pituitary makes. Replacement therapy when broken; risky as a "fountain of youth" when not.
Half-life
~3 hours
About 3 hours active — daily injections.
Dosing
Daily, subQ
How often you take a dose
Route
SubQ
How it goes into the body
Status
FDA
Approved by the FDA for prescription use
What it is
The actual hormone. FDA-approved as a prescription for kids who don't grow enough, and adults with diagnosed GH deficiency. Lots of off-label use for anti-aging — that's where it gets risky. Long-term over-replacement is linked to insulin resistance and possibly higher mortality.
The full technical answer
FDA-approved recombinant human growth hormone. Approved for pediatric GH deficiency, adult GH deficiency, and several wasting conditions. Off-label use for anti-aging is common but not FDA-supported.
How it works
Growth hormone tells your liver to release IGF-1, which then drives muscle growth, bone density, and metabolism. It's a normal part of how your body works — until you stop making enough (real deficiency) or take more than you need (the anti-aging risk zone).
The full technical answer
Identical to endogenous GH. Binds GH receptors, triggers IGF-1 release from liver, drives anabolic effects on muscle, bone, and metabolism.
What the research says
Decades of clinical use. Adult GH deficiency: improved body composition, lipids. Anti-aging use: high risk of insulin resistance, edema, joint pain.
Sources: NEJM Rudman 1990 · FDA Genotropin label
Common dosing ranges
- Range
- Adult deficiency: 0.15–0.3 mg/day. Anti-aging protocols: 1–2 IU/day.
- Frequency
- Daily, subQ
- Duration
- Long-term per medical indication
Sources: FDA Genotropin label
How to take it
Practical guidance synthesized from clinical protocols, FDA labels, and clinician interviews. Always cross-check with a prescribing physician.
Best time of day
Before bed (mimics natural pulsatile release), on an empty stomach. Some protocols split AM + PM.
With food or fasted
STRICTLY fasted — at least 2 hours after last meal. Carbs/insulin completely cancel the GH-driven lipolysis.
How long to cycle
Per medical indication (deficiency = ongoing). Off-label cycling: typically 5 days on, 2 days off; cycle 3–6 months on, 1 month off.
When to get off
Insulin resistance markers (rising fasting glucose, HbA1c), carpal tunnel symptoms, joint pain, edema. NEVER use with active malignancy.
Administration
Side effects
Common
- Edema
- Carpal tunnel
- Joint pain
- Insulin resistance
Serious / theoretical
- T2D
- Increased mortality (if elevated long-term per Rudman follow-up)
- Cancer growth concerns
Sources: FDA label
Further reading & listening
Where the experts go deeper.
Curated from the PeptideFacts expert directory — vetted YouTube channels, podcasts, books, and communities. No anecdote-only or supplier-affiliated picks.
Videos
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