All adults at risk of thunderstorm asthma need regular inhaled corticosteroids (ICS) for continuous use in the lead up to and during the grass pollen season, regardless of whether or not they usually take preventer therapy.
The new guidance was released today in version 1.3 of the Australian Asthma Handbook, which is now available online in a searchable format.
The majority of adolescents and adults with asthma should already be taking low dose ICS for continuous use, Professor Amanda Barnard, the chair of the National Asthma Council Australia Guidelines Committee and GP, said.
When preventer therapy was not otherwise indicated for patients, regular ICS was recommended for at least two weeks before and throughout the pollen season. Ideally, all patients with asthma would receive treatment from 1 September through to 31 December in Victoria.
The timing of the pollen season differs in other areas where thunderstorm asthma has been reported, which includes Canberra, Newcastle, Tamworth and Wagga Wagga.
The groups at risk for thunderstorm asthma are those with pre-existing asthma, those with allergic rhinitis, and patients with undiagnosed asthma. It is thought that thunderstorm asthma occurs when ryegrass pollens are swept up into the clouds then broken down into tiny particles.
It became evident during the thunderstorm asthma outbreak in Melbourne last year that some people with allergic rhinitis had undiagnosed asthma.
GPs could be more alert to these cases, Professor Barnard said.
“Ask your wheezers if they sneeze … but also ask all the people who sneeze about wheezing,” she said.
For patients with seasonal allergic rhinitis who do not use intranasal corticosteroid treatment all year, the Handbook advises they use it six weeks before the pollen season (or exposure) and continue until pollen levels abate.
The handbook also offers interim advice on asthma-COPD overlap, emphasising that this group of patients is at higher risk of flare-ups than patients with only one of these conditions.
The handbook provides updated advice on managing allergic rhinitis in people with asthma, recommending a combination of an intranasal corticosteroid (INCS) and an intranasal antihistamine for those patients whose symptoms are severe and are not controlled by INCS alone.