Urapidil is a peripheral postsynaptic alpha 1-adrenoceptor antagonist with central agonistic action at
serotonin 5-HT1A receptors. It reduces blood pressure by decreasing peripheral vascular resistance. Oral
urapidil decreases blood pressure in patients with mild to moderate
essential hypertension and associated risk factors such as hyperlipidaemia or type 2 (
non-insulin-dependent) diabetes mellitus with no effect on heart rate. The
antihypertensive efficacy of
urapidil is similar to that of most comparators in patients with mild to moderate essential or secondary
hypertension and no concomitant risk factors. However, the
antihypertensive efficacy of
urapidil was lower than that of
hydrochlorothiazide in a well designed trial.
Lipid levels and
glucose metabolism are not adversely affected and may improve with
urapidil in patients with
lipid or
glucose abnormalities.
Urapidil can be safely combined with other
antihypertensive agents such as
hydrochlorothiazide and
nifedipine and improves blood pressure control in previous nonresponders to monotherapy. Intravenous
urapidil reduces blood pressure in patients with
pre-eclampsia or
hypertension in pregnancy and in patients with
hypertensive crises or peri- or postoperative
hypertension. The decrease in blood pressure is similar to that observed after
nifedipine,
enalaprilat,
sodium nitroprusside and
dihydralazine, greater than that of
ketanserin according to 1 larger study, and greater than that of sublingual
nitroglycerin in 1 trial in patients with nonsurgical
hypertensive crises and pulmonary oedema. However, more patients responded to treatment with
urapidil than with
enalaprilat or
nifedipine. Heart rate is less likely to be altered by
urapidil than with some comparator drugs.
Urapidil appears to be well tolerated, with most adverse events being mild and transient. The incidence of adverse events with
urapidil is similar to that with
prazosin,
metoprolol,
atenolol,
sodium nitroprusside and
hydrochlorothiazide and less than that with
nifedipine and
clonidine.
Urapidil may not be as well tolerated as
captopril and, in 1 study, more
urapidil than
nitrendipine recipients discontinued treatment because of adverse events.
CONCLUSIONS: