Ocular responses in healthy subjects to topical bunazosin 0.3%--an alpha 1-adrenoceptor antagonist.

The ocular effects of the alpha-adrenoceptor blocking drug bunazosin, administered as eyedrops, have been measured in a placebo-controlled double-blind single-dose study in 15 healthy volunteers. The drug significantly reduced intraocular pressure over 10 hours, and there was no associated change in pulsatile ocular blood flow. Characteristic effects of alpha-adrenoceptor blockade were observed--miosis, ptosis, and conjunctival hyperaemia. The miosis alone persisted for more than 24 hours in nine out of 15 subjects.