Aqueous humor concentration of metoprolol after oral administration

The concentration of the beta-adrenergic blocking agent metoprolol was determined in the blood plasma and aqueous humor after oral administration of the compound. One group (10 cases) was receiving their prescribed continuous therapy and the other group (20 cases) received a single dose of metoprolol. The concentration of metoprolol was usually higher in aqueous than in plasma after continuous administration. This differs significantly from administration of a single dose where the concentration of metoprolol was higher in plasma. The result indicates an ocular accumulation of the drug in chronic systemic treatment.