ADCYAP1 and Erythema: For example, as a vasodilator peptide, PACAP has been shown to lead to temporary decreases in blood pressure and facial flushing (Li et al., 2007; Seeliger et al., 2010), accompanied by edema and erythema when applied in humans (Seeliger et al., 2010), although other studies have found no alteration of blood pressure (Chiodera et al., 1995).