Ventolin to Salamol--a crossover study in New Zealand.
AIMS: To assess asthma stability in adults converted from Ventolin to Salamol. METHODS: Thirty-six general practice adults with documented asthma and using Ventolin at least weekly in the previous 12 months, changed their Ventolin for Salamol for a period of 4 weeks. The validated Asthma Control Questionnaire was applied at the beginning and end of the study period. RESULTS: Of the 36 adults, 6/36 (17%; 95%CI 4-29%) prematurely withdrew mainly due to Salamol ineffectiveness. A further 15/36 (42%; 95%CI 25-58%) could not maintain Salamol alone and returned to Ventolin at some time during the study period with 10/15 (67%; 95% CI 42-91%) citing Salamol ineffectiveness. Of the remaining 15/36 who maintained the study design, nearly all had worse asthma stability 14/15 (93%; 95%CI 80-100%). CONCLUSIONS: Asthma stability was significantly worse with Salamol compared to Ventolin. Psychological features related to changing inhalers, different physical aspects of Salamol inhalers, and pharmacological ineffectiveness are possible explanations.