Ketoconazole inhibits the cytochrome P 450 system. However, patients taking ketoconazole with either formulation must be carefully observed. There have been reports of central nervous system disturbances documented with ingestion of immediate-release oxybutynin, as referenced herein. The incidence of these reports was similar in younger and older age groups. These central nervous system adverse effects may have been reported in more than one category and were not stratified by dosage.
Adverse events prevent patients from staying on an effective medication.
In the clinical trials of efficacy for controlled-release oxybutynin, the primary endpoint of staying on drug was the reduction of urge urinary incontinence episodes. The mean weekly urge incontinence episodes were reported carefully by patients utilizing voiding diaries. These patients had severe clinical bothersomeness with incontinence episodes ranging from 16 to 28 times per week. The average dose selected by most patients was in the range of 5 to 15 mg per day, and the dose was not influenced by age. Conclusion Development of new anticholinergic formulations and specifically a new drug delivery system for oxybutynin chloride represents a significant pharmacotherapeutic advance for the clinical problem of urge urinary incontinence or overactive bladder.