Background: Alosetron was reintroduced for treatment of irritable bowel syndrome with a risk management programme in November 2002. Recommended starting dosage was 1 mg/day for 4 weeks. If symptoms remained uncontrolled, dosage could be changed to 2 mg/day. Aim: To describe alosetron dosages and associated patient characteristics from the Lotronex follow-up survey programme. Methods: Patients reported dosages of alosetron at start and regular follow-up intervals. Analyses were limited to patients with the potential to have at least 1 year of follow-up (enrolled between 9 December 2002 and 31 December 2003). Results: At baseline, 75% of 2817 respondents reported starting on 1 mg/day, 17% on 2 mg/day and 8% on other doses. Adherence to recommended starting dosage did not vary by status at end of follow-up, previous alosetron experience or age. At last reported dose, 50% of respondents were using 1 mg/day; 29% were using 2 mg/day. Discontinuation was not related to baseline doses. Longer times to discontinuation were associated with previous use, symptoms for more than 6 months and dose change throughout follow-up. Conclusions: High adherence to recommended dosing at baseline and follow-up suggests that the risk management programme is encouraging safe use of alosetron, including adherence to dosing recommendations.
