Peptide side effects no one talks about BPC 157 headaches. TB 500 fatigue. CJC Ipamorelin water retention. Most people quit. But 90% of the time it's the protocol, not the peptide. What Is BPC 157? A Medical Clinic's Guide to the Body Protective Peptide, Its Uses, and What It Actually Does Perfect B Peptides are often well tolerated, but they can still cause temporary reactions while the body adapts. Some commonly reported effects include: BPC 157 headaches, nausea, increased appetite TB 500 The Stable Gastric Pentadecapeptide BPC 157 Pleiotropic Beneficial Activity and Its Possible Relations with Neurotransmitter Activity