Ocular toxicology of marijuana: an update

Abstract

This review, encompassing the basic and clinical effects of marijuana and several of its constituents on the eye, primarily covers the literature since 1981. Available toxicologic data are discussed with reference to the overall effects on the eye of the drugs derived from marijuana. Both the cannabinoids and water-soluble derivatives are presented in the framework of their potential development as glaucoma medications, based on new pharmacologic and toxicologic data. The cannabinoids, as represented by cannabigerol and new prodrugs, both of which have reduced toxicologic profiles, may provide a novel approach to their clinical use. The water-soluble compounds have been shown to cause morphologic effects in the eye that correlate with the changes in intraocular pressure. The possible modes of action of these compounds are presented. Considerable further work is needed with the water-soluble compounds, now discovered in several plant sources, to identify these common chemical moieties responsible for the reduction in intraocular pressure. Concurrent toxicologic studies are also needed to establish whether the responses seen with the parent molecules are duplicated with metabolites or lower-molecular-weight, active derivatives.