Doxazosin mesylate (UK 33274 mesylate)(UK 33274) is a quinazoline-derivative. It is a selectively antagonizes postsynaptic α1-adrenergic receptors.

Doxazosin D8 (UK 33274 D8) is a deuterium labeled Doxazosin (UK 33274).Doxazosin, a quinazoline derivative, selectively antagonizes postsynaptic AP1 adrenergic receptor.

Doxazosin (UK 33274) is a long-lasting inhibitor of α1-adrenoceptors that is widely used to treat benign prostatic hyperplasia and lower urinary tract symptoms.

Doxazosin HCl is the salt form of Doxazosin Free Base which acts by inhibiting the postsynaptic alpha(1)-adrenoceptors on vascular smooth muscle. This inhibits the vasoconstrictor effect of circulating and locally released catecholamines (epinephrine and norepinephrine), resulting in peripheral vasodilation.