In addition, recent researches on tirzepatide were not included in this analysis ( 2 Methods 2.1 Protocol Our systematic review and meta-analysis was executed and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement ( 2.2 Search strategy We conducted a systematic search of three electronic databases - namely, Embase, PubMed, and the Cochrane Library - to identify relevant literature published in English up to March 1, 2023
Oral formulations have become available, though they involve different pharmacokinetics and dosing protocols
in Archives of Pharmacal Research found that GHK-Cu increased follicle size and prolonged the growth phase in cultured human hair follicles (Pyo et al., 2007)

According to the UK SmPC, the most common side effects include: Nausea (very common, affecting more than 1 in 10 people): Usually most pronounced during the first few weeks of treatment and often diminishes with continued use Diarrhoea (common, affecting up to 1 in 10 people): Typically mild to moderate in severity Vomiting (common): More frequent at higher doses Constipation (common): May occur alongside other gastrointestinal effects Abdominal pain or discomfort (common): Relatively frequent during treatment initiation Decreased appetite (very common): An expected effect related to the medication's action Dyspepsia/indigestion (common): May contribute to discomfort after eating Beyond gastrointestinal effects, other recognised adverse reactions include injection site reactions (redness, itching, or swelling at the subcutaneous injection site), fatigue , and dizziness