Terazosin Labetalol

Antagonist Phenoxybenzamine Prazosin Doxazosin Terazosin Labetalol... 

Retrospective analysis of a large multinational study in patients given terazosin 5 or 10 mg daily found that terazosin only affected the blood pressure of patients taking beta blockers (atenolol, labetalol, metoprolol, sotalol, and timolol) if the blood pressure was uncontrolled. No change in blood pressure was seen in those with normal blood pressure (i.e. those without hypertension and those with hypertension controlled by beta blockers). The most common adverse effect in the 10-week terazosin phase was dizziness, and the incidence of this appeared to be lower in those taking antihypertensives (13 to 16%) than those not (21 to 25%)."... 

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