Dose-response effects of tropicamide HCl.

Using double-masking procedures, the mydriatic and cycloplegic effects of 0.25, 0.5, 0.75, and 1.0% tropicamide were studied. All doses produced clinically useful mydriasis of at least 6-mm pupils. Using testing conditions of both normal (35 ft-c) and bright (150 ft-c) illumination, no mydriatic dose-response differences for the four concentrations were found. Cycloplegic effects were dose related. A single drop of either 0.75 or 1.0% tropicamide reduced the amplitude of accommodation to about 1.5 D, which is adequate for a cycloplegic refraction.