[Antiglaucomatous effectiveness of beta receptor blockers with special reference to metipranolol]

Long-term treatment of glaucoma and ocular hypertension is being carried out increasingly by topical application of beta-adrenergic drugs. They bind to the beta 2-subtypes of beta-receptors in the unpigmented epithelia of the ciliary processes with high affinity. Aqueous humor production is thus inhibited. On the other hand the velocity of penetration through the cornea and the drug accumulation at this location increase with rising lipophilicity of the beta-blocker used. In this respect timolol and metipranolol, which was recently introduced on the Austrian market, possess favorable pharmacokinetic characteristics due to their intermediate lipophilicity. A calculation shows that one drop of 0.1% metipranolol solution produces supramaximal concentrations for several hours at the place of pharmacodynamic action. This is confirmed by the clinical efficacy, at the same time reducing the risk of local and systemic side effects.