Medication-related costs of rhinitis in Australia: a NostraData cross-sectional study of pharmacy purchases

PURPOSE: There is a relative paucity of research regarding medication expenditure associated with multiple-therapy use for rhinitis in Australia. To describe 1) the nature and extent of multiple-therapy use for rhinitis in Australia using data on therapies purchased with prescription or over-the-counter (OTC) and 2) additional costs incurred by multiple-therapy use compared with intranasal corticosteroid (INCS) therapy alone. PATIENTS AND METHODS: A retrospective observational study was carried out using a database containing anonymous pharmacy transaction data available from 20% of pharmacies in Australia that links doctor prescriptions and OTC purchase information. Pharmacy purchases of at least one prescription or OTC rhinitis treatment, with or without additional asthma/chronic obstructive pulmonary disease (COPD) therapy, by patients during 2013 and 2014 were assessed. RESULTS: In total, 4,247,193 prescription and OTC rhinitis treatments were purchased from 909 pharmacies over 24 months. The majority of rhinitis therapy transactions were single-therapy purchases without additional asthma/COPD therapy. Of the single therapies purchased, 73% were oral antihistamines (OAHs) and 15% were INCS therapy. Dual-therapy purchases of INCSs and OAHs accounted for 40% of multiple-therapy purchases. Patients frequently purchased OAHs, nonsteroidal nasal sprays, and eye drops for allergic conjunctivitis alongside INCSs, resulting in higher financial costs (up to AU$21 per treatment episode) compared with INCS monotherapy. CONCLUSION: This study highlighted the significant burden posed on community pharmacy to address the needs of people with rhinitis symptoms, and the failure to translate the evidence that INCSs are the most effective monotherapy for moderate to severe and/or persistent rhinitis into clinical practice in light of the lack of evidence supporting combination of INCS and OAH therapy. Health care professional engagement, especially at the pharmacy level, will be extremely important if we wish to ensure that the purchase of rhinitis treatment is in accordance with guidelines and that their use is optimal.