KPV is a tiny peptide of three amino acids (lysine, proline, valine) taken from the end of alpha-MSH, a natural hormone that calms inflammation. In animal and cell studies it reduced inflammation in the gut lining and the skin. There are no completed human trials yet, so it is an experimental option, not a treatment for conditions such as Crohn's disease or ulcerative colitis. A physician may consider it as an add-on, never as a replacement for proven care.

Thymosin Alpha-1 is a 28 amino acid peptide first found in the thymus, the gland that trains the immune system's T cells. Its synthetic form, thymalfasin (brand name Zadaxin), is approved as a medicine in more than 30 countries, mainly for chronic hepatitis B and as immune support. It helps regulate immune responses rather than simply boosting them. It is one of the better studied peptides, but it is still a prescription treatment that a physician should choose and monitor.

MOTS-c, SS-31 (elamipretide) and Humanin are peptides that act on the mitochondria, the parts of each cell that make energy. MOTS-c is studied for metabolism and exercise capacity, SS-31 for protecting the inner mitochondrial membrane, and Humanin for cell protection with age. SS-31 has the most human data and a US approval for one rare disease. MOTS-c and Humanin are still mostly studied in animals. None is a proven anti-ageing treatment, so a physician should decide whether one fits you.

Most scholars, including the Islamic Fiqh Academy, hold that non-nutritive injections under the skin or into the muscle do not break the fast, so a prescribed peptide pen can usually continue during Ramadan. The practical change is timing: most patients move their dose to after iftar or before suhoor. Weight-loss peptides need extra care because of dehydration and low blood sugar. Ask your physician to adjust your plan before Ramadan starts, and ask a trusted scholar if you are unsure about the religious ruling.