Ventolin is a beta-2-agonist, usually taken by inhaler, that works by relaxing the muscles in the airways which tighten during an asthmatic attack. This medication is foisted on children for even minor shortness of breath.
Top of the list is, ironically, bronchospasm, which occurs nearly 16 per cent of the time. This means that you have about a one in six chance of developing rebound shortness of breath or an asthmatic attack from the very drug you've taken to sort out the problem.
Another likely side-effect is tremors, which affects nearly 11 per cent of those taking the drug. Headache and cough both occur in 3 per cent of patients, and nearly 2 per cent develop wheezing, bronchitis, an increase in sputum or irregular breathing - symptoms that caused them to reach for a drug in the first place.
Beta-2-agonists are often automatically handed out with a prescription for a steroid - with all of its attendant side-effects. One study of these two drugs glorified how well they controlled asthma, but also parenthetically noted: 'The basic molecular mechanism of the interaction of the two drugs on proliferation of airway smooth muscle cells is yet to be identified' (Lancet, 2002; 360: 1293-9). That is medical-speak for: We haven't a clue how on earth these two drugs work when taken together.