title: Side effects of dihydropyridine therapy: comparison of amlodipine and nifedipine retard.
abstract: The efficacy and tolerability of amlodipine (5 mg, once daily), nifedipine retard (20 mg, twice daily), and placebo were compared in a multicenter, three-way, crossover study involving 97 patients with mild-to-moderate hypertension. Each patient underwent three, 2-week treatment periods separated by 2-week washout periods without therapy. Comparable and significant (p < 0.05) blood pressure reductions were observed after amlodipine and nifedipine retard when compared with placebo, except in the case of supine systolic blood pressure with nifedipine retard. A significantly greater incidence of treatment-related side effects was observed with nifedipine retard (41%) compared with amlodipine (27%, p < 0.05) or placebo (16%, p < 0.01). Amlodipine treatment was associated with significantly fewer reports of headache and flushing than nifedipine retard (p < 0.05). The lower incidence and reduced severity of vasodilator side effects associated with amlodipine resulted in fewer withdrawals and a better overall tolerability profile.
authors.affiliation: Great Western Medical, Glasgow, Scotland.
authors.forename: J
authors.initials: J
authors.lastname: Hosie
authors.forename: A D
authors.initials: AD
authors.lastname: Bremner
authors.forename: P J
authors.initials: PJ
authors.lastname: Fell
authors.forename: G V
authors.initials: GV
authors.lastname: James
authors.forename: P A
authors.initials: PA
authors.lastname: Saul
authors.forename: S H
authors.initials: SH
authors.lastname: Taylor
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017311:Amlodipine / Q000009:adverse effects* / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D003692:Delayed-Action Preparations; D004334:Drug Administration Schedule; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000009:adverse effects* / Q000627:therapeutic use*; D016037:Single-Blind Method
chemical_list: D003692:Delayed-Action Preparations; D017311:Amlodipine; D009543:Nifedipine