Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.
| Ipamorelin | Tesamorelin | |
|---|---|---|
| Category | Peptides | Peptides |
| Standard Dose | Research indicates 200-300 mcg administered 1-3 times daily via subcutaneous injection. | Research indicates 2 mg administered once daily via subcutaneous injection (FDA-approved dose for HIV lipodystrophy). |
| Timing | Best administered at bedtime for synergy with natural GH peak. Also effective upon waking and post-workout. Always on empty stomach. | Morning administration on empty stomach. Consistent daily timing recommended. |
| Cycle Duration | 12-24 week cycles with 4-8 week breaks. | 26+ weeks in clinical trials. Long-term use is common; effects are not sustained after discontinuation. |
| Evidence Level | moderate_human | Strong (FDA-approved indication), Moderate (longevity) |
Ipamorelin is a pentapeptide (Aib-His-D-2-Nal-D-Phe-Lys-NH2) that acts as the first selective growth hormone secretagogue receptor (GHS-R1a/ghrelin receptor) agonist. Unlike other GHRPs, it selectively stimulates GH release without significantly affecting ACTH, cortisol, prolactin, or aldosterone — even at doses 200-fold above the ED50 for GH release. This selectivity profile is comparable to GHRH itself but operates through the distinct ghrelin receptor on pituitary somatotrophs.
Research indicates 200-300 mcg administered 1-3 times daily via subcutaneous injection.
Best administered at bedtime for synergy with natural GH peak. Also effective upon waking and post-workout. Always on empty stomach.
12-24 week cycles with 4-8 week breaks.
Tesamorelin is an FDA-approved synthetic 44-amino acid GHRH analog with a trans-3-hexenoic acid modification at the N-terminal tyrosine that confers resistance to DPP-IV degradation. It binds GHRH receptors on anterior pituitary somatotrophs, stimulating endogenous GH production and secretion while maintaining pulsatile release patterns. Tesamorelin selectively reduces visceral adipose tissue (15-20% reduction in trials) while preserving subcutaneous fat, and markedly increases plasma GH and IGF-1 levels with once-daily dosing.
Research indicates 2 mg administered once daily via subcutaneous injection (FDA-approved dose for HIV lipodystrophy).
Morning administration on empty stomach. Consistent daily timing recommended.
26+ weeks in clinical trials. Long-term use is common; effects are not sustained after discontinuation.
Take our free assessment to get personalized recommendations based on your health goals, current stack, and biomarkers.
Get Your Free Protocol →or take the assessment →