Fesoterodine
Pronunciation: pronunciation varies by local usage.
- Generic name
- fesoterodine
- Brand names
- TOVIAZ
- Drug class
- Antimuscarinic medicine
- Form
- Prolonged-release or extended-release tablet
- Route
- Oral
- Legal status
- Country-specific supply classification not established in this source set
Availability and supply rules vary by country
Trade names by country: United States · Canada
Australia: · Full directory
What fesoterodine is and how it works
Fesoterodine is an antimuscarinic medicine used to treat symptoms that can occur with overactive bladder, including urinary urgency, increased urinary frequency, and urge or urgency urinary incontinence. (1) (2)
It is used in adults according to the UK source. The US source describes treatment of overactive bladder with urge urinary incontinence, urgency, and frequency. Suitability depends on conditions that can increase the risks of urinary retention, gastrointestinal effects, glaucoma, and anticholinergic adverse effects.
Mechanism of action: how fesoterodine works
Fesoterodine is described in the supplied sources as an antimuscarinic medicine. Further pharmacology detail was not extracted in the supplied notes. (1) (2)
What fesoterodine is used for
Overactive bladder symptoms
Fesoterodine is used for overactive bladder symptoms, including increased urinary frequency, urinary urgency, and urge or urgency urinary incontinence. The UK source specifies this use in adults. (1) (2)
Before taking fesoterodine
Do not take / not appropriate for
- Do not take fesoterodine if you have urinary retention, gastric retention, uncontrolled narrow-angle glaucoma, or hypersensitivity to fesoterodine or tolterodine tartrate formulations. (United States label) (1)
- Do not take fesoterodine if you have hypersensitivity to fesoterodine, peanut, soya, or an excipient; urinary retention; gastric retention; uncontrolled narrow-angle glaucoma; myasthenia gravis; severe hepatic impairment; severe ulcerative colitis; or toxic megacolon. (United Kingdom SmPC) (2)
- In the United Kingdom, fesoterodine is contraindicated with a potent CYP3A4 inhibitor when moderate-to-severe renal or hepatic impairment is present. (United Kingdom SmPC) (2)
Tell your clinician about
- Difficulty passing urine, a weak urine stream, bladder outlet obstruction, or benign prostatic hyperplasia.
- Severe constipation, reduced bowel movement, gastrointestinal obstruction, pyloric stenosis, gastro-oesophageal reflux, ulcerative colitis, toxic megacolon, or autonomic neuropathy.
- Narrow-angle glaucoma, myasthenia gravis, kidney impairment, liver impairment, or a previous allergic reaction to fesoterodine, tolterodine, peanut, soya, or product ingredients.
- A history of QT-interval prolongation, low potassium, slow heart rate, palpitations, or medicines that can prolong the QT interval.
- All medicines and supplements, particularly anticholinergic medicines, gastrointestinal motility stimulants, CYP3A4 inhibitors or inducers, CYP2D6 inhibitors, and St John's Wort.
- Pregnancy, plans for pregnancy, breastfeeding, or fertility concerns.
How to take fesoterodine
- Take fesoterodine once daily with liquid and swallow the tablet whole. Do not chew, divide, or crush it.
- It may be taken with or without food; the US label states that food does not significantly affect absorption.
- The usual starting dose in the supplied US and UK sources is 4 mg once daily. A clinician may increase this to a maximum of 8 mg once daily according to individual response and tolerability.
- Do not change the dose yourself. Kidney function, liver function, and interacting medicines can change the maximum appropriate dose or whether use is appropriate.
- The UK SmPC reports that full effect may be seen after 2 to 8 weeks and advises reassessment of efficacy after 8 weeks.
Procedures and treatment changes
Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2)
Missed dose
Follow the exact product instructions and do not double a dose.
Overdose
An overdose can cause severe anticholinergic effects. Seek urgent medical or poison-information advice if too much may have been taken. Treatment is symptomatic and supportive, and ECG monitoring is recommended in the supplied sources. (1) (2)
Side effects
Dry mouth and constipation are among the most frequently reported effects. Anticholinergic effects can also affect vision, alertness, sweating, bowel function, and the ability to pass urine.
Dry mouth
What to notice: A dry mouth was very common in the UK source and occurred more often at higher doses in the US trial data.
What to do: Discuss persistent or troublesome dry mouth with the prescribing clinician or pharmacist. (1) (2)
Constipation or other digestive symptoms
What to notice: Constipation, abdominal pain, diarrhoea, dyspepsia, nausea, and dry throat may occur.
What to do: Contact the clinician promptly if constipation is severe or if there are symptoms of bowel obstruction or gastric retention. (1) (2)
Dizziness, headache, sleepiness, or blurred vision
What to notice: Dizziness, headache, somnolence, blurred vision, and confusional state were reported.
What to do: Use caution with driving or machinery if vision or alertness is affected, and discuss troublesome symptoms with the clinician. (1) (2)
Urinary symptoms or urinary tract infection
What to notice: Dysuria, urinary tract infection, urinary hesitation, and urinary retention have been reported.
What to do: Contact the prescribing clinician promptly if it becomes difficult to pass urine or the bladder cannot be emptied. (1) (2)
Urinary retention
What to notice: Difficulty starting urination, inability to pass urine, worsening urinary hesitation, or a feeling that the bladder cannot empty.
What to do: Seek prompt medical assessment. Post-marketing cases requiring catheterisation have been reported, particularly in older male patients with a history consistent with benign prostatic hyperplasia. (1) (2)
Palpitations or heart-rate symptoms
What to notice: Palpitations or a fast heartbeat.
What to do: Contact the prescribing clinician promptly for assessment, particularly if there are QT-prolongation risk factors. (1) (2)
Serious warnings
Angioedema or serious hypersensitivity reaction — emergency
Symptoms: Swelling of the face, lips, tongue, or larynx; hives; itching; facial swelling; or breathing or airway symptoms.
Action: Seek emergency medical help immediately, especially for tongue, throat, laryngeal, or breathing involvement. Angioedema may be life-threatening and has occurred after the first dose in some cases. (1) (2)
Severe anticholinergic effects or overheating — urgent
Symptoms: Severe constipation or urinary retention, marked drowsiness, confusion, blurred vision, or reduced sweating and heat prostration in a hot environment.
Action: Obtain urgent medical assessment. Alcohol can increase drowsiness, and heat exposure can be hazardous when sweating is decreased. (1) (2)
Interactions
| Medicine or test | Effect | Action |
|---|---|---|
| Other antimuscarinic or anticholinergic medicines | Effects can be additive, increasing dry mouth, constipation, urinary retention, and other anticholinergic effects. | Give the clinician and pharmacist a complete medicines list before starting or changing treatment. (1) (2) |
| Potent CYP3A4 inhibitors | Medicines such as ketoconazole, itraconazole, clarithromycin, ritonavir, and atazanavir can increase exposure. The maximum fesoterodine dose is 4 mg daily in the supplied sources; the UK SmPC has additional contraindications with renal or hepatic impairment. | A clinician or pharmacist must check all interacting medicines and kidney and liver function before use. (1) (2) |
| Moderate CYP3A4 inhibitors | Fluconazole, erythromycin, diltiazem, verapamil, and grapefruit juice can increase exposure. The supplied US and UK sources state that no dose adjustment is needed in general, but UK renal and hepatic impairment tables set further restrictions. | Ask the clinician or pharmacist to assess the full combination rather than making a dose change independently. (1) (2) |
| CYP3A4 inducers | Rifampin can reduce exposure by about 70% to 75% in the US source. The UK SmPC states that concomitant potent inducers, including carbamazepine, rifampicin, phenobarbital, phenytoin, and St John's Wort, are not recommended. | Tell the prescriber and pharmacist about these medicines or supplements because efficacy may be reduced and regional advice differs. (1) (2) |
| CYP2D6 inhibitors and gastrointestinal motility stimulants | The UK SmPC states that potent CYP2D6 inhibitors may increase exposure and adverse events, and that antimuscarinic medicines may reduce the effect of gastrointestinal motility stimulants such as metoclopramide. | Have a clinician or pharmacist review these combinations. (2) |
| Oral contraceptives and warfarin | The supplied sources report no clinically significant effect on oral contraceptive efficacy and no significant effect on warfarin pharmacokinetics; the US label also reports no significant effect on anticoagulant activity. | Continue standard warfarin monitoring as directed by the responsible clinician. (1) (2) |
Pregnancy, breastfeeding, kidney/liver function, age
Older adults
The US label states that no adjustment is needed based on age alone, but antimuscarinic adverse events occurred more often in people aged 75 years and over. Older adults, especially those with bladder outlet obstruction, may need careful assessment for urinary retention. (1) (2)
Children and adolescents
The US label states that safety and effectiveness in pediatric patients have not been established. The UK indication in the supplied source is for adults. (1) (2)
Pregnancy and breastfeeding
The UK SmPC does not recommend fesoterodine during pregnancy or breastfeeding because human pregnancy data are inadequate and it is unknown whether fesoterodine or its metabolites enter human milk. The US label states it should be used during pregnancy or nursing only when potential benefit outweighs potential risk. Discuss this with the prescriber. (1) (2)
Kidney or liver impairment
Kidney and liver impairment can affect whether fesoterodine can be used and the maximum dose, particularly with CYP3A4 inhibitors. Severe hepatic impairment is not recommended in the US label and is contraindicated in the UK SmPC. (1) (2)
Monitoring
Before starting
- Confirm that symptoms are appropriate for overactive bladder and exclude organic causes before antimuscarinic treatment, as stated in the UK SmPC.
- Assess urinary retention risk, bladder outlet obstruction, gastrointestinal conditions, glaucoma, myasthenia gravis, anticholinergic adverse-effect risk, and allergy history.
- Review kidney function, liver function, QT-prolongation risk factors, and all medicines and supplements for interactions.
- Confirm the locally applicable dose restrictions and contraindications.
During treatment
- Assess symptom response and tolerability. The UK SmPC states that full effect may be observed after 2 to 8 weeks and recommends reassessing efficacy after 8 weeks.
- Monitor for dry mouth, constipation, urinary retention, blurred vision, dizziness, confusion, palpitations, allergic reactions, and reduced sweating in hot environments.
- Reassess interacting medicines, kidney function, and liver function when clinically relevant, especially if CYP3A4 inhibitors are used.
Storage
Store in the original package or tightly closed bottle to protect from moisture. The US label states to store at 20°C to 25°C, with permitted excursions from 15°C to 30°C. The UK SmPC states not to store above 25°C.
Professional information
Clinician-facing context only. Use the current local product information, contraindications, renal and hepatic impairment tables, and interaction guidance.
United States
Indication: Overactive bladder with urge urinary incontinence, urgency, and frequency
Dose summary: Start 4 mg once daily; may increase to 8 mg once daily based on individual response and tolerability. Maximum is 4 mg daily with severe renal impairment (CLcr less than 30 mL/min) or potent CYP3A4 inhibitors. No adjustment is stated for CLcr 30 to 80 mL/min, mild to moderate hepatic impairment (Child-Pugh A or B), moderate CYP3A4 inhibitors, or CYP2D6 poor metabolizers. Severe hepatic impairment (Child-Pugh C) is not recommended.
Renal context: For severe renal impairment (CLcr less than 30 mL/min), maximum 4 mg daily. For mild to moderate impairment (CLcr 30 to 80 mL/min), no adjustment is needed according to the US label. (1)
United Kingdom
Indication: Treatment of overactive bladder syndrome symptoms in adults
Dose summary: Start 4 mg once daily and may increase to a maximum of 8 mg once daily according to individual response. Dose and permissibility vary by GFR, hepatic impairment, and CYP3A4 inhibitor strength. With potent CYP3A4 inhibitors, maximum dose is 4 mg where use is permitted; combinations with moderate-to-severe renal or hepatic impairment are contraindicated. Severe hepatic impairment is contraindicated.
Renal context: Mild impairment (GFR 50 to 80): 4 to 8 mg normally; 4 mg with a moderate CYP3A4 inhibitor; avoid with a potent inhibitor. Moderate impairment (GFR 30 to 50): 4 to 8 mg normally; 4 mg with a moderate inhibitor; potent inhibitor combination contraindicated. Severe impairment (GFR less than 30): 4 mg only; avoid with a moderate inhibitor; potent inhibitor combination contraindicated. (2)
Hepatic guidance
United States: no adjustment is stated for mild or moderate hepatic impairment, while severe impairment (Child-Pugh C) is not recommended. United Kingdom: mild impairment permits 4 to 8 mg normally, moderate impairment permits 4 mg normally, and severe impairment is contraindicated; CYP3A4 inhibitor restrictions apply.
Overdose note
Overdose can cause severe anticholinergic effects. The supplied sources advise symptomatic and supportive treatment and ECG monitoring. The UK SmPC lists management measures that may be used according to clinical presentation. (1) (2)
Frequently asked questions
Can I crush or split a fesoterodine tablet?
No. The supplied US and UK product information says to swallow the tablet whole with liquid. Do not chew, divide, or crush it. (1) (2)
How long can fesoterodine take to have its full effect?
The UK SmPC states that full effect may be observed after 2 to 8 weeks and advises reassessment of efficacy after 8 weeks. (2)
Can I take fesoterodine with grapefruit juice?
Grapefruit juice is listed as a moderate CYP3A4 inhibitor. The supplied sources state that no general dose adjustment is needed with moderate inhibitors, but kidney or liver impairment can create additional restrictions under the UK SmPC. Ask a clinician or pharmacist to review your individual combination. (1) (2)
What should I do if my lips, tongue, or throat swell?
Seek emergency medical help immediately. Fesoterodine has been associated with angioedema involving the face, lips, tongue, or larynx, which may be life-threatening. (1) (2)
What is the mechanism of action of fesoterodine?
Fesoterodine is described in the supplied sources as an antimuscarinic medicine. Further pharmacology detail was not extracted in the supplied notes. (1) (2)
References
- DailyMed: TOVIAZ (fesoterodine fumarate) extended-release tabletsDailyMed, U.S. National Library of Medicine (FDA-approved label) · United States · accessed 2026-07-23 · source 1
- UK electronic Medicines Compendium: TOVIAZ 4 mg / 8 mg prolonged-release tablets Summary of Product Characteristicselectronic Medicines Compendium (UK SmPC) · United Kingdom · accessed 2026-07-23 · source 2
- FESOTERODINE FUMARATE TABLET, EXTENDED RELEASE [ASCEND LABORATORIES, LLC] — US prescribing information (DailyMed SPL)U.S. National Library of Medicine (DailyMed) · US · accessed 2026-08-14 · source 3
- Fesoterodine — patient drug information (MedlinePlus)U.S. National Library of Medicine (MedlinePlus) · US · accessed 2026-08-14 · source 4
- Fesoterodine Fumarate — FDA approval record (Drugs@FDA ANDA205002)U.S. Food and Drug Administration · US · accessed 2026-08-14 · source 5
- fesoterodine — RxNorm normalized drug concept (RXCUI 797195)U.S. National Library of Medicine (RxNorm) · US · accessed 2026-08-14 · source 6
Brand names by country
Single-ingredient fesoterodine names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.
Priority countries
United States
- Toviaz8 mg, 4 mg · pfizer laboratories div pfizer inc
Canada
- TOVIAZ