although such drugs as sodium nitroprusside , diazoxide , dihydralazine , and clonidine have been very useful and effective in the past in the treatment of severe arterial hypertension , they are now being replaced by drugs as nifedipine , urapidil , captopril , and co-dergocrine mesylate , which maintain cerebral and coronary blood flow while effective by lowering blood pressure .
C0028066
nifedipine
C0020649
lowering blood pressure