New research shows that asthma inhalers can stunt the growth of children by up to half a centimetre.
Scientists measured the effects of corticosteroid inhalers on 8,000 young people aged 18 and under.
Use of asthma inhalers was found to cut half a centimetre from an average annual growth rate of six to nine centimetres.
However, they also accepted that such a small loss of growth was a welcome benefit if it meant that potentially lethal asthma attacks were prevented.
They also found that loss of growth could be prevented by lower doses of the asthma treatment.
Samantha Walker, director of research and policy at the charity Asthma Research UK, said: “Half a centimetre in growth is a small price to pay for medicine which may save your child’s life.
“Uncontrolled asthma can substantially increase the likelihood of asthma attacks, hospitalisation and even death and we know that inhaled steroids, taken regularly, significantly reduce the likelihood of these events happening.
“For a long time now people with asthma have told us they fear the side effects of taking asthma medicines but the good news is this evidence shows only a relatively minor impact from inhaled corticosteroids.
“No parent should therefore stop their children taking these lifesaving medicines.”
The review looked at 25 trials different trials that incolved a total of 8,471 children and teenagers.
Fourteen of the trials, with 5,717 participants, reported growth over the course of a year.
A second review by the same researchers examined data from 22 trials in which children were treated with low or medium doses of inhaled corticosteroids.
Only three trials followed 728 children for a year or more. In these trials, reducing inhaler doses by about one puff a day improved growth by a quarter of a centimetre per year.
Lead author Dr Linjie Zhang, from the Federal University of Rio Grande in Brazil, said: “The evidence we reviewed suggests that children treated daily with inhaled corticosteroids may grow approximately half a centimetre less during the first year of treatment.
“But this effect is less pronounced in subsequent years, is not cumulative, and seems minor compared to the known benefits of the drugs for controlling asthma and ensuring full lung growth.”