Moreover, no significant differences in CYP2C9*3 frequency were found between the PHT-induced DRESS (OR 1.88; 95%CI 0.5024–7.0773, p = 0.3472) and PHT-induced MPE (OR 0.53; 95%CI 0.0617–4.5929, p = 0.5663), when compared with tolerant control group. The gene discussed is CYP2C9; the disease is pulmonary hypertension, primary, 1.