Stroke is the third most common cause of death in developed countries. In England and Wales, 1000 people under the age of 30 have a stroke each year. Cocaine is the most commonly used class A drug, and the first report of cocaine-induced stroke was in 1977. Since the development of alkaloidal "crack" cocaine in the 1980s, there has been a significant rise in the number of case reports describing both ischaemic and haemorrhagic stroke associated with cocaine use. Cocaine is a potent central nervous system stimulant, and acts by binding to specific receptors at pre-synaptic sites preventing the reuptake of neurotransmitters. The exact mechanism of cocaine-induced stroke remains unclear and there are likely to be a number of factors involved including vasospasm, cerebral vasculitis, enhanced platelet aggregation, cardioembolism, and hypertensive surges associated with altered cerebral autoregulation. The evidence surrounding each of these factors will be considered here.

Stroke is a recognised complication of pregnancy, contributing to more than 12% of all maternal deaths. Estimated incidence rates vary considerably from 4.3 to 210 strokes per 100 000 deliveries. Atherosclerosis is rare in young adults, and so other causes of stroke become increasingly likely. Aetiological factors important in pregnancy include hypercoagulability due to maternal physiological changes, pre-eclampsia and eclampsia, cerebral venous thrombosis, paradoxical embolism, postpartum cerebral angiopathy and peripartum cardiomyopathy. Management of patients with pregnancyrelated stroke should generally proceed as for nonpregnant patients, although there are a number of important areas specific to pregnancy which will be considered here.Stroke in young adults aged 15-35 years is more common in women than in men, 1 and women also have poorer outcomes in terms of disability and dependency.2 There has been growing interest in the role of oestrogens in stroke, 3 and risk factors unique to women include pregnancy, use of oral contraceptives, and postmenopausal hormone therapy. Stroke associated with pregnancy has been recognised for many years, and is an uncommon but feared complication contributing to more than 12% of all maternal deaths.4 5 The declining incidence of direct causes of maternal death has led to an increased awareness of nonobstetric factors such as stroke. Clearly, any recognised cause of stroke in young patients may also occur coincidentally during pregnancy, although there are a number of factors associated with pregnancy that have an important aetiological role, and these will be considered here. We will also consider the current scope of the problem, and focus on relevant areas unique to pregnancy, including issues surrounding investigation and treatment options.

Drug induced parkinsonism is the second most common cause of parkinsonism in older people after idiopathic Parkinson's disease (PD). Risk factors for developing drug induced parkinsonism include: older age; female gender; dose and duration of treatment; type of agent used; cognitive impairment; acquired immunodeficiency syndrome (AIDS); tardive dyskinesia; and pre-existing extrapyramidal disorder. In most patients parkinsonism is reversible upon stopping the offending drug, though it may take several months to resolve fully and in some patients it may even persist. In this case, one needs to consider the possibility of PD which has been unmasked by the offending drug, and treatment with dopaminergic agents may be warranted. Drug induced parkinsonism adversely affects the quality of life in older patients and is potentially reversible, highlighting the importance of early recognition of this condition. This article discusses the drugs implicated, as well as the epidemiology, pathophysiology, clinical features, and management of drug induced parkinsonism.