ghk-cu peptide benefits and uses REMEDY Copper Complex Advanced Firming Serum – Remedy Science by Dr. Muneeb Shah GHK-Cu Dosage and Protocol: A
Description
It is also known as lipotropin and Tyr-hGH fragment, and is generally available these days as a transdermal cream or an injectable.

Its now widely used in both dermatology and trichology for improving skin texture, reducing wrinkles, and, most importantly for our discussion, revitalising hair follicles

The numbness

Technically yes, but the risk profile changes significantly
52 TrakadisY.AlfaresA.BodamerO.ChristodoulouJ.ConnorP.NordwallM.et al (2014)

CD38 can act as an inflammatory mediator, contributing to the development of myocardial I/R injury and cerebral ischemia diseases [8, 28, 65]