Tens of thousands of people are at risk of potentially life-threatening asthma attacks because they are not being correctly prescribed inhalers, a charity has warned. Asthma UK said more than 22,000 people with asthma in the UK – including 2,000 children – have been incorrectly prescribed long-acting reliever inhalers, which carry a black box warning in the United States because they are unsafe if not used appropriately.