Illicit drugs, appetite suppressants, decongestants, and anabolic steroids may cause stroke. Drug abuse is a common cause of stroke in young patients. Mechanisms are varied, but it is particularly important to seek out infective endocarditis and most importantly, cerebral aneurysms, vascular malformations, and cardiac disorders in cocaine abusers. Drug-induced vasoconstriction, hypertension, or vasculitis probably contributes significantly to most patients' strokes. Tobacco smoking and heavy chronic alcohol consumption are independent risk factors for stroke; moderate drinking seems to protect from stroke in white patients. Oral contraceptives may increase the risk of stroke in female patients over 35 years of age who also have other risk factors.