Anticholinergics. Some hospitals use anisodamine (654-2) instead of aminophylline for the treatment of HAPE. Anisodamine can improve pulmonary vascular spasms, decrease pulmonary vascular resistance and hypoxic pulmonary hypertension, improve the pulmonary microcirculation, and maintain smooth pulmonary blood flow. As a result, anisodamine inhibits intravascular coagulation and, thus, reduces the risk of pulmonary embolism.