Drug Rash and Eruption: Symptoms, Pictures, Causes, and Treatment Drug Allergy Program Allergy and Immunology Programs Q: Why can peptides sometimes cause flushing, itching, or redness?, A: Because some peptides can turn that alarm up too fast., This can happen when:, The dose is high, The body absorbs it quickly, Penicillin allergy often inaccurately recorded by healthcare professionals The Pharmaceutical Journal What causes a localized histamine reaction after a CJC (Growth Hormone Releasing Hormone) ipamorelin injection? Rash from a GLP 1 explained by an allergist , Thanks to my friend @rubin_allergy for the information in this video.