Over-the-counter β2-agonist purchase versus script: a cross-sectional study

Abstract

Background: Purchase of short-acting β(2)-agonist (SABA), but not anti-inflammatory asthma medication, is permitted in Australia without a doctor's prescription. This has been associated with worse asthma outcomes. We sought to compare the asthma outcomes between those purchasing SABA with and without a doctor's prescription.

Design: Cross-sectional study, using stratified randomisation of pharmacies.

Setting: 43 pharmacies in Victoria, Australia.

Participants: Up to 10 consecutive adults purchasing β(2)-agonists were recruited from each pharmacy, with 316 adults in total.

Outcome measures: Participants underwent spirometry and questionnaires on respiratory health, asthma control, Quality of Life and medication adherence. Asthma severity was determined by GINA medication step. Regression analyses were performed that allowed for clustering by pharmacy.

Results: Of 316 individuals recruited (65% participation rate), 191 (60%) purchased a β(2)-agonist with a prescription. Purchase of SABA without prescription was not associated with worse asthma outcomes or lung function. Mean (±SD) asthma control score (ACQ) was 1.65 ± 1.03; only 63 (20%) had well-controlled asthma (ACQ < 0.75). Anti-inflammatory asthma medication was owned by 188 (60%) of participants, of whom 157 (83%) reported using this in the last 7 days. There was no correlation between medication adherence scores and asthma control. Forty-seven participants (15%) had an FEV(1) below 80% predicted and did not own an anti-inflammatory asthma medication.

Conclusion: Purchase of SABA without prescription was not associated with worse asthma outcomes in Australia. Although many patients reported symptoms of asthma, this did not appear to be associated with reported adherence to anti-inflammatory asthma medication.