ATC Group: C02CA Alpha-adrenoreceptor antagonists

Doxazosin is a potent and selective post-junctional alpha-1-adrenoceptor antagonist. This action results in a decrease in systemic blood pressure.

Indoramin is an alpha adrenoceptor blocking agent. It acts selectively and competitively on post-synaptic alpha-1 receptors, causing a decrease in peripheral resistance. It also produces relaxation of hyperplastic muscle in the prostate.

Prazosin causes a decrease in total peripheral vascular resistance through selective inhibition of postsynaptic alpha-1-adrenoreceptors in vascular smooth muscle. Prazosin has been found to successfully reduce the severity of the signs, symptoms, frequency and duration of attacks, in patients with Raynaud’s disease.

Urapidil is a α1-adrenoceptor antagonist and 5-HT1A receptor agonist and consequently inhibits the vasoconstrictor effect of catecholamines. It interacts with peripheral α1-adrenoceptors and central 5-HT1A receptors to produce vasodilation without sympathetic activation.