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The stimulant methamphetamine, also known as “speed”, “ice” and “meth”, is linked to a heightened risk of stroke among young people, according to a review of the available evidence by authors from the National Drug and Alcohol Research Centre, published in the Journal of Neurology, Neurosurgery and Psychiatry. Haemorrhagic stroke is more commonly associated with the use of this drug than ischaemic stroke, with men twice as likely to succumb as women, the findings show. The authors were looking for a potential link between methamphetamine use and associated stroke risk in young people (under the age of 45 years), and their findings were based on a review of 370 articles published to February 2017, of which 77 case reports and series were selected for analysis. Some 81 haemorrhagic and 17 ischaemic strokes were reported. Both types were about twice as common in men as they were in women. In the case reports and series, eight of ten strokes associated with methamphetamine use by young people were haemorrhagic. This rate is much higher than reported rates of this type of stroke in people under the age of 45 years (40–50%) or in older people (15–20%), the researchers emphasised. Methamphetamine can be swallowed, inhaled or injected; haemorrhagic strokes were associated with swallowing or injecting the drug, while inhalation was the most common route associated with ischaemic stroke. Haemorrhagic stroke was associated with vascular abnormalities, such as high blood pressure and vasculitis, in one-third of cases. Repeated use of methamphetamine can increase blood pressure even in people whose blood pressure is initially normal, say the researchers. Risk of death was also higher after a haemorrhagic stroke: one in four people recovered completely, but one-third died. This compares with complete recovery for one in five people and death in one in five after an ischaemic stroke.