Doctors should rethink the common practice of advising four-hourly maximum salbutamol inhaler use in children discharged after an asthma attack, a group of experts has warned, calling the approach a “myth”.

Recommending that children take up to 10 puffs of salbutamol every four hours as part of a post-discharge weaning plan, reducing the dose day-by-day could mean that signs of deterioration are not spotted as well as encouraging over-reliance on short-acting β2-agonists (SABA), said UK clinicians writing in the European Respiratory Society journal Breathe.

High use of salbutamol inhalers may also lead to tolerance to their bronchodilator effects, lessening their efficacy and creating a cycle where more is perceived to be needed, they added. 

While the use of weaning plans has crept in over the past two decades, there is little evidence to support this approach, the authors said.

It means salbutamol weaning plans advising regular high-dose SABA “in the aftermath of an asthma attack is both unnecessary and actually dangerous”, they wrote.

The team of clinicians from the National Heart and Lung Institute and Royal Brompton Hospital, London, pointed to two randomised trials comparing “as needed” inhaler use with regular doses for adult patients in hospital with an asthma attack which found no clinical differences but reduced SABA use overall in those taking it as and when.

There is also an argument that such weaning plans run counter to global efforts to reduce the carbon footprint of asthma inhalers.

It is widely accepted that regular over-use of salbutamol is harmful and that SABA drugs do not treat the underlying inflammation driving an asthma attack, the group concluded. They noted the National Review of Asthma Deaths (NRAD) which found the greatest vulnerability to be in the four weeks after an attack.

So why encourage over-use of salbutamol, itself a risk factor for asthma death, at a point when children are most vulnerable, they added.

The current evidence for optimal care in this group after discharge is inadequate but the approach should be one of asthma education, a personal action plan, vigilance about prescribing and ensuring adherence to maintenance therapy.

Co-author Dr Mark Levy, a GP with a special interest in respiratory diseases as well as clinical lead for the NRAD, said the practice was “dangerous and takes away the warning signs”.

“It teaches people that this is how you manage their children’s asthma and instils a false sense of security”, he told the limbic.

For children up to the age of 11, parents should be advised to use salbutamol as necessary but doctors should ensure they are also prescribing an inhaled or oral corticosteroid to treat the underlying condition, said Dr Levy who is also on the board of directors for the GINA guidelines.

Another option is a combination inhaler with budesonide and formoterol, he added.

“If salbutamol is not lasting four hours, the child needs to be in hospital. Treatment needs to be optimised before you send someone home.”