title: Antihypertensive effectiveness of the nifedipine gastrointestinal therapeutic system.
abstract: The results of a multicenter trial conducted in order to determine the therapeutic efficacy of the gastrointestinal therapeutic system (GITS) formulation of nifedipine in comparison with hydrochlorothiazide and placebo in the management of mild to moderate essential hypertension are presented. During a one-week wash-out phase, antihypertensive therapy was discontinued in all patients. After a three-week single-blind placebo period, eligible patients were randomly assigned in a double-blind fashion to one of three treatment groups for a one-week titration period and a nine-week efficacy period. Patients received either nifedipine GITS, 30 or 60 mg daily; hydrochlorothiazide, 25 or 50 mg daily; or placebo. Sitting and standing blood pressures decreased by an average 11.6/10.4 and 10.8/10.8 mm Hg, respectively, with nifedipine GITS therapy, and 14.8/10.8 and 14.3/8.2 mm Hg, respectively, with hydrochlorothiazide therapy. Compared with placebo, these changes were highly significant for both sitting (p less than or equal to 0.005) and standing (p less than or equal to 0.02) measurements. Heart rate remained essentially unchanged in all three groups. It was therefore concluded that monotherapy with nifedipine GITS, at doses of 30 or 60 mg given once daily, effectively reduces blood pressure in patients with hypertension to a degree comparable with that seen in hydrochlorothiazide therapy.
authors.affiliation: Department of Medicine, Boston City Hospital, Massachusetts.
authors.forename: I
authors.initials: I
authors.lastname: Gavras
authors.forename: R
authors.initials: R
authors.lastname: Mulinari
authors.forename: H
authors.initials: H
authors.lastname: Gavras
authors.forename: J T
authors.initials: JT
authors.lastname: Higgins
authors.forename: R L
authors.initials: RL
authors.lastname: Reeves
authors.forename: E T
authors.initials: ET
authors.lastname: Zawada
authors.forename: J
authors.initials: J
authors.lastname: Crook
authors.forename: A K
authors.initials: AK
authors.lastname: Halperin
authors.forename: B
authors.initials: B
authors.lastname: Garrett
mesh_terms: D000328:Adult; D000368:Aged; D002986:Clinical Trials as Topic; D003692:Delayed-Action Preparations; D004311:Double-Blind Method; D004341:Drug Evaluation; D005260:Female; D006801:Humans; D006852:Hydrochlorothiazide / Q000008:administration & dosage; D006973:Hypertension / Q000188:drug therapy*; D007408:Intestinal Absorption; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D009543:Nifedipine / Q000008:administration & dosage* / Q000493:pharmacokinetics
chemical_list: D003692:Delayed-Action Preparations; D006852:Hydrochlorothiazide; D009543:Nifedipine