Marihuana and the Treatment of Glaucoma

Abstract

Glaucoma is a group of diseases in which elevated intraocular pressure (IOP) in conjunction with unknown aberrant neural factors causes a specific type of progressive optic-nerve degeneration and loss of vision. To date, reduction of IOP, whether by means of medications, or laser or invasive surgery, constitutes the only principle of treatment of proven efficacy Marihuana inhalation or Delta(9)-THC administered intravenously, or orally, reduces IOP in glaucoma. This effect is of short duration and undetermined mechanism. It has not yet been elicited by topical administration. Neither marihuana nor any cannabinoids thus far tested could meet the standards of approval by the United States Food and Drug Administration (FDA) for treatment of glaucoma. Further investigation of the mechanism of action of marihuana in glaucoma should be pursued. Meanwhile, a trial on oral dronabinol (Delta(9)-THC), which is available as a Shedule II narcotic agent under the Controlled Substances Act, might be considered for patients with glaucoma in whom all approved methods of treatment, including surgery, have failed to stop progressive visual deterioration. [References: 21]