MK-677 (Ibutamoren) vs Melanotan I
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
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 →Melanotan I
Melanotan I (afamelanotide) is a synthetic analog of alpha-melanocyte-stimulating hormone (α-MSH). It is FDA-approved as Scenesse for erythropoietic protoporphyria (EPP), a rare genetic disorder causing severe sun sensitivity.
Full details →Side-by-Side Comparison
| Aspect | MK-677 (Ibutamoren) | Melanotan I |
|---|---|---|
| Mechanism | 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 melanocortin 1 receptors (MC1R) on melanocytes, stimulating eumelanin production. This increases skin pigmentation and provides photoprotection without UV exposure. |
| Typical Dosage | Typical dosing: 10-25mg taken orally once daily. Often taken at night due to sleep benefits and appetite increase. | Clinical: 16mg implant every 2 months. Research protocols for tanning typically use 0.5-1mg daily for loading, then maintenance dosing. |
| Administration | Oral administration (capsule or liquid). Can be taken with or without food. Long half-life allows once-daily dosing. | FDA-approved form is a subcutaneous implant. Research use involves subcutaneous injection. Often combined with minimal UV exposure to enhance results. |
| Side Effects | Increased appetite and water retention are most common. May cause lethargy, vivid dreams, and mild numbness. Can affect blood glucose and insulin sensitivity. | Nausea (especially initially), facial flushing, fatigue, headache, and darkening of existing moles or freckles. |
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