Hexarelin vs MK-677 (Ibutamoren) vs Sermorelin
A three-way comparison to help you find the right peptide for your research goals.
Hexarelin
Hexarelin is a potent synthetic hexapeptide growth hormone secretagogue. It provides the strongest GH release among GHRPs but is associated with rapid desensitization of receptors.
Full details →MK-677 (Ibutamoren)
MK-677, also known as Ibutamoren, is an orally active growth hormone secretagogue. Unlike peptides, it can be taken orally and has a long half-life, providing 24-hour GH elevation.
Full details →Sermorelin
Sermorelin is a synthetic analog of GHRH consisting of the first 29 amino acids of the natural hormone. It was previously FDA-approved for GH deficiency diagnosis and treatment in children.
Full details →Side-by-Side Comparison
| Aspect | Hexarelin | MK-677 (Ibutamoren) | Sermorelin |
|---|---|---|---|
| Mechanism | Acts as a ghrelin mimetic with high potency at the GHS receptor. Provides powerful GH release but receptor desensitization occurs faster than with other GHRPs, requiring cycling. | Acts as a potent, selective agonist of the ghrelin receptor (GHS-R1a). Increases GH and IGF-1 levels without affecting cortisol. Mimics ghrelin's GH-releasing effects. | Binds to GHRH receptors in the pituitary gland to stimulate natural GH production and release. Maintains the body's natural feedback mechanisms for GH regulation. |
| Typical Dosage | Typical dosing: 100-200mcg administered 2-3 times daily for 4-6 weeks, followed by an equal off period to allow receptor resensitization. | Typical dosing: 10-25mg taken orally once daily. Often taken at night due to sleep benefits and appetite increase. | Typical dosing: 200-500mcg administered once daily, usually before bed. Some protocols use twice daily dosing. |
| Administration | Subcutaneous injection. Cycling is essential to maintain effectiveness. Often used in short bursts rather than continuous protocols. | Oral administration (capsule or liquid). Can be taken with or without food. Long half-life allows once-daily dosing. | Subcutaneous injection, preferably at bedtime to work with natural GH release patterns. Can be combined with GHRPs for synergistic effects. |
| Side Effects | Water retention, cortisol and prolactin increase, hunger (moderate), tingling, and potential blood pressure effects. | Increased appetite and water retention are most common. May cause lethargy, vivid dreams, and mild numbness. Can affect blood glucose and insulin sensitivity. | Generally well-tolerated. May cause injection site reactions, headache, flushing, or dizziness. Less side effects than direct GH administration. |
| Best For |
What They Have in Common
Hexarelin, MK-677 (Ibutamoren), Sermorelin are all commonly used for:
Key Differences
Unique to MK-677 (Ibutamoren):
Unique to Sermorelin:
Detailed Analysis
Commonalities
Both Hexarelin and MK-677 (Ibutamoren) are commonly used for Muscle Growth, Recovery & Healing.
Which Should You Choose?
Both peptides have similar evidence levels for their shared goals. Your choice may depend on specific use case, availability, or personal response.
Commonalities
Both Hexarelin and Sermorelin are commonly used for Muscle Growth, Recovery & Healing.
Which Should You Choose?
Hexarelin has stronger evidence for Muscle Growth.
Commonalities
Both MK-677 (Ibutamoren) and Sermorelin are commonly used for Muscle Growth, Fat Loss, Recovery & Healing, Sleep Quality.
Which Should You Choose?
MK-677 (Ibutamoren) has stronger evidence for Muscle Growth, Sleep Quality.