Calcium Channel Blockers
Calcium channel blockers, such as nifedipine (Procardia), amlodipine besylate (Norvasc), and diltiazem hydrochloride (Cardizem), are used initially if the patient had a positive response to the vasodilator challenge. Calcium channel blockers act on vascular smooth muscle to dilate the pulmonary vessels, causing a decrease in MPAP and PVR and increase in CO. Calcium channel blockers are administered orally and can be used long term to effectively manage PH. The dosage may vary from patient to patient.