Peptide Comparison

Ipamorelin vs Sermorelin

A detailed comparison to help you understand the differences and choose the right peptide for your research.

Ipamorelin and Sermorelin are two of the most popular growth hormone stimulating peptides, but they work through different mechanisms. Ipamorelin is a GHRP (Growth Hormone Releasing Peptide) that mimics ghrelin, while Sermorelin is a GHRH (Growth Hormone Releasing Hormone) analog. Understanding their differences is crucial for optimizing GH enhancement protocols.

Quick Comparison

Aspect

Ipamorelin

Sermorelin

Class

GHRP (Growth Hormone Releasing Peptide) - ghrelin mimetic

GHRH (Growth Hormone Releasing Hormone) analog

Mechanism

Activates ghrelin receptors (GHSR) in pituitary

Activates GHRH receptors in pituitary

FDA History

Research peptide, never FDA approved

Previously FDA approved for pediatric GH deficiency

Effect on Cortisol

Minimal - very selective for GH

Minimal - maintains natural regulation

Effect on Hunger

Minimal - much less than GHRP-6

None

GH Release Pattern

Pulsatile, mimics natural release

Pulsatile, very physiological

Typical Dose

100-300 mcg per dose

Dosing Frequency

2-3 times daily

Once daily (before bed)

Best Timing

Morning and/or before bed

Before bed for optimal results

Synergy

Enhanced when combined with GHRH

Enhanced when combined with GHRP

Key Similarities

Both stimulate natural GH production from the pituitary
Both produce pulsatile GH release patterns
Both have good safety profiles with minimal side effects
Both require subcutaneous injection
Both work best on an empty stomach
Both are commonly used for anti-aging and body composition

Key Differences

Different receptor targets (ghrelin receptor vs GHRH receptor)
Sermorelin has FDA approval history; Ipamorelin does not
Ipamorelin typically dosed multiple times daily; Sermorelin once at night
Ipamorelin may have slight hunger effect; Sermorelin none
Sermorelin has longer research history; Ipamorelin is newer
They work synergistically together rather than being alternatives

When to Choose Each

Choose Ipamorelin

Choose Ipamorelin when you want a clean GH secretagogue with minimal side effects, especially as part of a combined GHRP+GHRH protocol. Its selectivity for GH without affecting other hormones makes it the 'cleanest' GHRP option.

Choose Sermorelin

Choose Sermorelin when you prefer a single daily dose before bed and value its FDA approval history and extensive research. It's particularly popular for anti-aging clinics due to its established safety profile.

Can You Stack Them?

Ipamorelin and Sermorelin are often used together in a GHRP+GHRH stack. This combination can produce synergistic GH release that exceeds either peptide alone. The typical protocol is taking both together before bed, with some adding a morning dose. CJC-1295 without DAC (Mod GRF 1-29) is another popular GHRH to combine with Ipamorelin.

Frequently Asked Questions

When used alone at typical doses, they're similar. However, combining a GHRP like Ipamorelin with a GHRH like Sermorelin produces significantly more GH than either alone.

Yes, this is actually ideal. GHRP + GHRH combinations are synergistic, potentially producing 5-10x more GH release than either peptide alone.

Both have minimal side effects. Ipamorelin is notable for not affecting cortisol or prolactin. Sermorelin's long history shows excellent tolerability.

Both are popular for anti-aging. Sermorelin has more clinical history in this application, while Ipamorelin's selectivity is appealing. Many anti-aging protocols use both together.

References

Raun K, et al. "Ipamorelin selectivity." Eur J Endocrinol, 1998. PMID: 9758455
Walker RF. "Sermorelin clinical use." Drugs, 2006. PMID: 16929329

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