[The influence of metoprolol eye drops on intraocular pressure (author's transl)]

The selective beta-1 blocker Metoprolol was tested for a period of one month in a double-blind trial involving 36 patients with open-angle glaucoma or intraocular hypertension in whom the substance was applied twice daily to the eye in concentrations of 1, 2, 4 and 8%. At all these concentrations the intraocular pressure showed a reduction of 23%. The concentrations over 1% were less well tolerated, the difference being statistically significant; the patients concerned complained of an unpleasant burning sensation for 30 seconds after the application. The subjective intolerance shown increased in proportion to the concentration. It is not clear whether the solvent used contributed to the intolerance. The Metoprolol drops had no effect on pupillary diameter, blood pressure or resting pulse. An important finding was that during the one month's treatment there was no fall-off in the effectiveness of the preparation, i.e., the reduction in intraocular pressure and duration of action showed no diminution such as is seen, for example, with Timolol.