Allergic bronchopulmonary aspergillosis (ABPA) can cause a significant clinical deterioration in patients with cystic fibrosis. There is very little research in the current literature with regard to alternatives for treatment, apart from long courses of steroids. We conducted a retrospective review of all our patients with ABPA treated with the antifungal voriconazole and found there was a significant drop in IgE levels post treatment as well as a decrease in steroid dosing. The improvement in FEV was not statistically significant; however there was a very wide variation in pre-treatment levels.