The antimuscarinic drug solifenacin is associated with significantly fewer side effects than another drug in the same class, oxybutynin, according to Canadian researchers.
Antimuscarinics are prescribed for overactive bladder but many patients discontinue taking them because they experience dry mouth, said the researchers in the Journal of Urology.
They compared the tolerability and safety of two of the drug class in 132 patients with overactive bladder symptoms. Patients were randomised to 5mg solifenacin once daily or 5mg oxybutynin three times daily for eight weeks.
They found 35 per cent of patients taking solifenacin reported dry mouth compared with 83 per cent of those receiving oxybutynin.
The authors said: “Although antimuscarinic treatment is indicated for overactive bladder, many patients discontinue it because of dry mouth. Of available antimuscarinics oxybutynin is associated with the highest dry mouth rate.
“Significantly fewer patients on solifenacin reported moderate/severe dry mouth. Significantly fewer patients on solifenacin withdrew from study due to dry mouth and there were significantly fewer overall adverse events.”