MK-677 (Ibutamoren) vs Thymosin Alpha-1
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 →Thymosin Alpha-1
Thymosin Alpha-1 is a peptide naturally produced by the thymus gland that plays a crucial role in immune system modulation. It is approved in over 35 countries for various conditions including hepatitis B and C.
Full details →Side-by-Side Comparison
| Aspect | MK-677 (Ibutamoren) | Thymosin Alpha-1 |
|---|---|---|
| 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. | Enhances T-cell function and maturation, stimulates dendritic cell activity, and modulates cytokine production. Promotes the differentiation of stem cells into mature T lymphocytes. |
| Typical Dosage | Typical dosing: 10-25mg taken orally once daily. Often taken at night due to sleep benefits and appetite increase. | Clinical dosing typically ranges from 1.6mg to 6.4mg administered subcutaneously 2-3 times weekly. Research protocols may vary. |
| Administration | Oral administration (capsule or liquid). Can be taken with or without food. Long half-life allows once-daily dosing. | Subcutaneous injection. Often used in cycles or as part of comprehensive immune support protocols. |
| 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. | Generally well-tolerated. Rare side effects include injection site reactions, mild flu-like symptoms, and temporary fatigue. |
| Best For |
What They Have in Common
Both MK-677 (Ibutamoren) and Thymosin Alpha-1 are commonly used for: