Sydney researchers have raised concerns about the over-prescribing of asthma preventer medicine.

More than seven out of 10 patients over the age of 12 are affected.

The experts, from the the Woolcock Institute of Medical Research, in an article published at Australian Prescriber, an independent pharmaceutical watchdog, advise how doctors can help their patients through a process of stepping down their potentially toxic doses.

The evidence

A 2020 study from the Alfred Hospital, Monash University and others  found that 71 per cent of Australian adults and adolescents were prescribed controller-inhaled corticosteroids that contained higher doses than those recommended in the national guidelines.

More worrying, the study found that 25 per cent of people with asthma who use inhaler controllers ‘‘are dispensed potentially toxic cumulative oral corticosteroid doses’’.

These drugs are greatly beneficial to people with asthma, a condition ‘‘which entails risks of severe respiratory attacks and death’’, corticosteroids have a range of serious side effects when the doses are high or cumulatively toxic.

These include osteoporosis and fracture, diabetes, cataracts, weight gain, sleep apnoea, renal impairment, pneumonia, myocardial infarction, heart failure, stroke, dyslipidaemia and depression.

Respiratory physician Professor Helen Reddel.

The authors of the 2020 study asserted that ‘‘many clinicians are unaware that toxic effects can develop after relatively low cumulative doses’’.

What the experts advise

Lead author of the new article, Professor Helen Reddel, is respiratory physician and a research leader in the clinical management group at the Woolcock Institute of Medical Research.

She is a member of the Australian Asthma Handbook guidelines committee and her research focuses on strategies to improve the management of asthma.

She advises that, while asthma treatment isn’t a ‘one size fits all’ scenario, most of the benefit of asthma preventer inhalers ‘‘is seen with low doses’’.

She writes that a key goal for clinicians is to customise treatment for the needs of each patient.

This involves ‘‘finding the lowest dose that will keep asthma symptoms well controlled and reduce the risk of severe attacks (also called severe flare-ups or exacerbations), while minimising the risk of adverse effects’’.

Professor Reddel and her co-authors advise:

• Asthma guidelines recommend considering a step-down in preventer treatment after asthma has been well controlled for two to three months in adults and for six months in children
• The step-down process should be individualised for each patient
• Preventive therapy should not be stopped completely without medical advice.

Professor Reddel said: “If your asthma has been stable for more than three months, check with your doctor. It may be possible to reduce the dose.”

One in nine Australians suffer with asthma.

Read the article in Australian Prescriber.