Recent medication use of 3,394 members of the Group Health Cooperative of Puget Sound (GHC) diagnosed with an incident work-related injury was compared to that of two controls selected from the GHC membership and matched on age, gender, and Standard Industrial Classification Code of their employer. Medication use was determined from the GHC pharmacy data base. The injuries of the cases included 496 fractures or dislocations, 2,728 open wounds, crushing injuries, or superficial injuries, 176 burns, and 64 internal or intracranial injuries. The risk of injury was elevated among users of antihistamines [odds ratio (OR) = 1.5, 95% confidence interval (CI) = 1.1-1.9], antibiotics (OR = 1.2, 95% CI = 1.0-1.5), and diabetes medications (OR = 1.3, 95% CI = 0.9-1.9). The patterns of risk were similar for males and females, but varied by type of injury. No consistent associations between use of antidepressants, antianxiety medication, or narcotics and work-related injury were observed. The use of some medications, or conditions requiring medications, may contribute to the risk of a work-related injury.