Extended-release formulations of oxybutynin and tolterodine exhibit similar central nervous system tolerability profiles: a subanalysis of data from the OPERA trial.
OBJECTIVE
This study was undertaken to compare the central nervous system (CNS) tolerability profiles of the extended-release formulations of oxybutynin chloride and tolterodine tartrate in the treatment of women with overactive bladder (OAB), as observed in the OPERA (Overactive bladder: Performance of Extended Release Agents) trial.


METHODS
The OPERA trial was a randomized, double-blind, active-control comparison of the efficacy and safety of extended-release oxybutynin (10 mg/d) and extended-release tolterodine (4 mg/d) given to 790 women with OAB for 12 weeks. The incidence of reported CNS events was compared between the treatment groups by using the Fisher exact test.


RESULTS
The incidence of CNS adverse events was 9% and 8% for the oxybutynin and tolterodine treatment groups, respectively. The difference between groups was not statistically significant. All reported CNS adverse events were rated as mild or moderate in severity. There were no serious treatment-related adverse events in either group, and discontinuation because of a CNS adverse event was infrequent.


CONCLUSIONS
The extended-release formulations of oxybutynin and tolterodine were observed to be associated with a similar low incidence of CNS adverse events, which were mostly mild or moderate in severity.
Chu
Franklin M
FM
San Bernardino Urological Associates, CA 92404, USA. FMCSBU@aol.com
Dmochowski
Roger R
RR
Lama
Daniel J
DJ
Anderson
Rodney U
RU
Sand
Peter K
PK
D001559:Benzhydryl Compounds / Q000008:administration & dosage* / Q000009:adverse effects; D002490:Central Nervous System / Q000187:drug effects; D003408:Cresols / Q000008:administration & dosage* / Q000009:adverse effects; D003692:Delayed-Action Preparations; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008333:Mandelic Acids / Q000008:administration & dosage* / Q000009:adverse effects; D018727:Muscarinic Antagonists / Q000008:administration & dosage* / Q000009:adverse effects; D010665:Phenylpropanolamine / Q000008:administration & dosage* / Q000009:adverse effects; D016032:Randomized Controlled Trials as Topic; D000068737:Tolterodine Tartrate; D014549:Urinary Incontinence / Q000188:drug therapy* / Q000503:physiopathology
D001559:Benzhydryl Compounds; D003408:Cresols; D003692:Delayed-Action Preparations; D008333:Mandelic Acids; D018727:Muscarinic Antagonists; D010665:Phenylpropanolamine; D000068737:Tolterodine Tartrate; C005419:oxybutynin