Safety of beta-adrenergic blocker washout period in clinical trials.

We prospectively evaluated the safety of the washout period from topical beta-adrenergic blockers prior to clinical drug trials. In 30 consecutive patients optic disc parameters (neural rim, optic disc, peripapillary halo and atrophy areas, and venous/arterial diameters) did not change following washout (p > 0.05). Likewise, the mean defect and pattern standard deviation (Humphrey 30-2) did not change following washout (p > 0.05). This study suggests, generally, the safety of the washout period prior to clinical drug trials.