title: Acute hypotensive response to nifedipine.
abstract: Nifedipine, an effective hypotensive drug in severe hypertension, was investigated by invasive methods in 15 hypertensive patients while they were supine, erect, and exercising moderately. The effects of oral nifedipine 20 mg examined 45 minutes after the dose showed a reduced systemic arterial blood pressure via a reduction in peripheral resistance. Nifedipine reduced pulmonary arterial pressure and pulmonary wedge pressures (PWP) during exercise in patients with abnormally high values but did not alter them in patients with normal values. Heart rate and cardiac output increased by a reflex mechanism. The decreases in arterial blood pressure and PWP correlated with the initial values while the increases in heart rate and cardiac output did not correlate with the extent of blood pressure reduction. Since nifedipine decreases arterial blood pressure, pulmonary arterial pressure, and PWP in proportion to the pretreatment values, it is a useful drug in severe hypertension with and without elevated pulmonary pressures.
mesh_terms: D000328:Adult; D000959:Antihypertensive Agents / Q000627:therapeutic use; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000627:therapeutic use*; D005082:Physical Exertion; D011187:Posture; D011725:Pyridines / Q000627:therapeutic use*
chemical_list: D000959:Antihypertensive Agents; D011725:Pyridines; D009543:Nifedipine