Tolerability and compliance with risedronate in clinical practice.

The purpose of this study was to determine compliance with dosing instructions, and the prevalence of possible adverse events, when risedronate is used in clinical practice. 219 patients were studied. We found that despite counseling one in four patients were non-compliant with dosing instructions. Those patients who did not stay upright after taking risedronate were more likely to have an adverse event and to discontinue the drug. Adverse events were experienced by 38% of patients, the commonest being gastrointestinal. Upper GI adverse events occurred in 21% of patients. A previous history of upper GI symptoms applied to 44% of patients and significantly more of them experienced upper GI adverse events than those with no history of GI problems. Forty two (19%) of patients taking risedronate stopped therapy due to adverse events, but only ten of these patients had contacted the Osteoporosis Unit about these symptoms. Approximately one third of the patients who experienced adverse events in this study had attempted a rechallenge with the drug. This was worthwhile, however, as in almost 50% of these patients their symptoms settled and they continued with therapy. This study has highlighted the importance of following up patients on long-term osteoporosis medication to ensure optimal compliance. The use of specialized osteoporosis nurses in clinics or primary care to follow up patients needs to be addressed.