The passage of the Missouri generic drug law in 1979 did not increase the dispensing of generic antiglaucoma medications, nor did it reduce retail prices. In 1976 and in 1980, antiglaucoma medications purchased with generic prescriptions were no less expensive than medications purchased with brand-name prescriptions. Almost all generic prescriptions were filled with brand-name products. A wide range of prices (approximately twofold) was noted from pharmacy to pharmacy for each drug. The retail cost of antiglaucoma medication increased approximately 35% between March and April 1976 and July and August 1980. This was less than the increase in the Consumer Price Index for the urban United States during the same period.