Mild asthma might not need to be treated every day, say US researchers.A "preventer" inhaler containing corticosteroid is part of many asthma sufferers' daily routine, but it can result in reduced growth and children often forget to take it.This study, published in The Lancet, shows that it is possible to manage the symptoms without a daily dose.Asthma UK said daily treatment was still the most effective, and concerned patients should speak to their doctor.The disease causes inflammation of the tubes which carry air to and from the lungs. If they become irritated, then the airways narrow, sticky mucus is produced and breathing becomes difficult.More than 5 million people in the UK are being treated for the illness and Asthma UK estimates 1.1 million have asthma which is mild and under control.Missing dosesResearchers at the University of Arizona believe there is a problem with the way the disease is managed.Two types of inhalers are used: "relievers" which are used when breathing is difficult and "preventers" which are taken every morning and evening.However, the researchers said that many children stop taking the daily medication if their symptoms disappear.Professor Fernando Martinez, from the University of Arizona, told the BBC: "If you have a daily drug and a very significant number are not taking it, then that tells you it's a losing strategy.""We want to find something which is more child- and parent-friendly as well as avoid the growth effect."In all, 288 children and teenagers with mild and persistent asthma took part in the 44-week trial.The study showed that taking corticosteroids twice a day was still the most effective treatment, However, those taking the medication grew by 1.1cm (0.5in) less than children not taking the drug during the trial.Potent combinationImportantly, asthma was also managed without daily treatment if the corticosteroids were combined with the "reliever" inhaler.This eliminated the effect on growth and the researchers say it would be an easier form of treatment for children.Further clinical trials will be needed to verify the results.Professor Martinez said: "I'm continuing to recommend daily corticosteroid to my patients, but I know some of them will not take it."Asthma UK said the study confirmed that daily inhaled corticosteroids were the most effective treatment.Dr Samantha Walker, executive director of research and policy at Asthma UK, said: "We know that long-term adherence to medicine treatment plans can be difficult, particularly when a child's asthma seems to be under control."The use of combined 'preventer' and 'reliever' medicines as rescue therapy appears to be superior to 'reliever' inhalers alone and offers a new 'step-down' approach to the management of mild, well-controlled asthma in children and young people who find it difficult to adhere to long-term daily treatment with inhaled steroids."Many parents have concerns about their child's steroid intake. However, research shows that children on low daily doses of 'preventer' medicines show no difference in growth. At higher doses, the picture is less clear. For all children, treatment plans should be reviewed at least every six months."If you have any concerns about your asthma treatment, Asthma UK recommends you speak to your doctor or asthma nurse."Source: BBC