Many people think injecting peptides like BPC 157, GHK Cu, or TB500 directly over a painful area sends the peptide straight into the damaged tissue. But thats not how it works. When you inject Tylenol (acetaminophen) is one of the most commonly used painkillers. It is safe for kids, during pregnancy, and while breastfeeding. However, just because it is safe, doesn't mean that it Figure 1: CMAJ Phases 1 and 2 acetaminophen metabolism. Acetaminophen consumed in Download Scientific Diagram