Alpha-adrenoceptor blocking drugs

Alpha-adrenoceptor blocking drugs

Alpha-blockers, α-blockers, or α-adrenergic-antagonists are pharmacological agents that act as antagonists of α-adrenoceptors. Drugs can be non-selective, antagonising both α1 and α2 receptor subtypes, or may be selective for one subtype over the other.

α-blockers are most commonly used to treat hypertension, but are also widely used to treat symptoms of BPH (benign prostatic hyperplasia). Raynaud's disease symptoms are also responsive to α-blocker therapy, although efficacy in this condition has not been clearly established.

Side-effects common to all α-blockers include the risk of hypotensive events (especially following first dose), dizziness, drowsiness, dry mouth and headache. Many side-effects lessen over time.

Non-selective α-blockers

phenoxybenzamine (for control of hypertensive episodes associated with Phaeochromocytoma)

phentolamine (for control of hypertensive episodes associated with Phaeochromocytoma and local anesthetic reversal- not UK approved)

α1-selective blockers

alfuzosin (symptomatic relief in benign prostatic hyperplasia, BPH)

prazosin (BPH, hypertension)

doxazosin (BPH, hypertension)

terazosin (BPH, hypertension)

silodosin (BPH)

tamsulosin (BPH)

indoramin (BPH) 

α2-selective blockers

mirtazapine (treatment of episodes of major depression)