to assess the clinical effects of switching from anti-anginal treatment with beta blocker only ( phase i ) to half-dose beta blocker plus the calcium blocker nifedipine ( phase ii ) or nifedipine alone ( phase iii ) , 18 patients with chronic stable angina pectoris and side effects to beta blockers were evaluated in a 12-week , open-label trial .
C0028066
nifedipine
C0340288
chronic stable angina