© The Canadian Journal of Urology™; 19(Supplement 1); October 2012
7
Medical management of overactive bladder
TABLE 5.
Antimuscarinic medications for overactive bladder
Name (Brand name)
Dosage and adjustments
Main side effects*
,†
Darifenacin
7.5
mg-15 mg daily
Dry mouth, constipation,
(
Enablex)
Dose should not exceed 7.5 mg in moderate hepatic
low rate of cognitive impairment
impairment. Avoid use in severe hepatic insufficiency.
Dose should not exceed 7.5 mg in those on potent CYP3A4
inhibitors.
‡
Use with caution with other substrates of CYP2D6
that have a narrow therapeutic window (e.g., trycyclic
antidepressants), since their clearance may be reduced
Fesoterodine
4
mg-8 mg daily
Dry mouth, constipation,
(
Toviaz)
Doses should not exceed 4 mg in severe renal impairment
dry eyes, low rate
(
CrCl < 30 mL/min) and those on potent CYP3A4 inhibitors;
‡
of cognitive impairment
should not be used in severe hepatic impairment
Oxybutynin ER
5
mg-30 mg daily
Dry mouth, constipation,
(
Ditropan XL, Uromax) Not studied in renal or hepatic impairment
blurred vision/dry eyes,
and cognitive impairment
Oxybutynin gel 10%
1
gram applied to skin daily
Skin irritation or pruritus,
(
Gelnique)
Apply to abdomen, thighs or upper arms/shoulders. Rotate
low incidence of dry mouth
application sites. Not studied in renal or hepatic impairment
and constipation
Oxybutynin IR
5
mg bid-qid
Significant dry mouth,
(
Ditropan)
Use with caution in patients with renal or hepatic disease
constipation, and cognitive
impairment
Oxybutynin
1
patch applied twice weekly (delivers 3.9 mg/day)
Skin irritation or pruritus,
transdermal patch
Rotate application sites. Use with caution in
low incidence of dry mouth
(
Oxytrol)
patients with renal or hepatic impairment
and constipation
Solifenacin
5
mg-10 mg daily
Dry mouth, constipation,
(
Vesicare)
Doses should not exceed 5 mg in severe renal impairment
blurred vision/dry eyes,
(
CrCl < 30 mL/min) or moderate hepatic impairment, and
low rate of cognitive impairment
those on potent CYP3A4 inhibitors;
‡
should not be used in
severe hepatic impairment
Tolterodine
1
mg-2 mg bid
Dry mouth, constipation,
(
Detrol)
Doses should not exceed 1 mg bid in patients with
blurred vision/dry eyes,
impaired hepatic function or renal impairment,
and lower rate of cognitive
and those on potent CYP3A4 inhibitors.
‡
impairment. Reports of worsening
dementia when initiated
in patients taking cholinesterase
inhibitors for dementia
Tolterodine ER
2
mg-4 mg daily
Dry mouth, constipation,
(
Detrol LA)
Doses should not exceed 2 mg daily in patients with
blurred vision, and lower rate
impaired hepatic function or renal impairment, and those
of cognitive impairment
on potent CYP3A4 inhibitors.
‡
Reports of worsening dementia
when initiated in patients taking
cholinesterase inhibitors
for dementia
Trospium
20
mg bid, must be taken on an empty stomach (at least
Dry mouth, constipation,
(
Trosec [Canada],
1
hour before meals). Dose should not exceed 20 mg hs
blurred vision/dry eyes,
Sanctura and
in patients ≥ 75 yrs or those with severe renal impairment
possible lower rate
Sanctura XR [US])
(
CrCl 15-30 mL/min). Not studied in moderate
of cognitive impairment
or severe hepatic dysfunction, or severe renal impairment
with CrCl < 15 mL/min.
Dose for extended release formulation
[
Sanctura XR; US only] is 60 mg daily (at least 1 hour before meals)
bid = twice a day; CrCl = creatinine clearance; ER = extended release; hs = at bedtime; IR = immediate release; qid = four times a day
*
See individual product monographs for a complete list of side effects
†
Cognitive impairment (confusion, dementia, delerium, etc.) more commonly observed in elderly patients
‡
Examples of potent CYP3A4 inhibitors include ketoconazole, clarithromycin, erythromycin, ritonavir, verapamil, and others
