Comparison of effects on cerebral blood flow of rapid reduction in systemic arterial pressure by diazoxide and labetalol in hypertensive patients: preliminary findings.

Abstract

1 Diazoxide 300 mg and labetalol 150 mg were each injected intravenously on separate occasions into five patients with essential hypertension. The reduction in BP caused by labetalol was slightly greater than that produced by diazoxide. 2 In contrast the reduction in cerebral blood flow (CBF) by labetalol was not statistically significant, whereas diazoxide gave a greater and statistically significant reduction in CBF. 3 These observations suggest that labetalol may have an advantage over diazoxide for the rapid reduction in BP.

Comparison of labetalol with other anti‐hypertensive drugs.

“…In addition diazoxide significantly reduced cerebral blood flow, although changes with labetalol were not significant (Pearson et al, 1979). Rosei et al (1976) have reported one case where labetalol 150 mg intravenously was used to control blood pressure after a hypertensive crisis from clonidine withdrawal, and in a patient with aortic dissection it was used as a continous infusion to control the blood pressure (Cumming & Davis, 1979).…”

Labetalol, an alpha‐ and beta‐adrenoceptor‐blocking agent: its use in therapeutics. A summary of the symposium.

“…Earlier work has indicated that labetalol is more potent as an antihypertensive agent than weight for weight comparability with propranolol as a fl-blocker had inferred (Pugsley et al, 1976 (Dargie et al, 1976;New Zealand Hypertension Group 1979;Williams et al, 1979). blood flow induced by labetalol in contrast to diazoxide (Pearson et al, 1979). The report of Ghose (1979) has also indicated that oral labetalol is a useful approach in the control of severe hypertension.…”

“…Labetalol 150 mg intravenously produced a marginally greater fall in BP than diazoxide 300 mg (Pearson et al, 1979). It seems, however, that the preferred method of intravenous administration in these circumstances is by infusion where the reduction in blood pressure is probably easier to control (Cumming et al, 1979a).…”

Blood Pressure in Acute Stroke: Causes and Consequences

“…Combined alfa-and betablockers such as labetalol do not seem to have a similar deleterious effect on cerebral blood flow (78) and can be used if acute antihypertensive therapy is needed in stroke patients. Calcium antagonists are widely used to patients with ischemic or hemorrhagic stroke.…”

“…Cerebral blood flow decreases after acute administration of diazoxide (78), clonidine (79) and betablockers (80)(81).…”