What the label lists and what reports show
Fesoterodine side effects
Fesoterodine's FDA label: “Most frequently reported adverse events with Toviaz in adult patients with OAB (≥4%) were: dry mouth (placebo, 7%; Toviaz 4 mg, 19%; Toviaz 8 mg, 35%) and constipation (placebo, 2%; Toviaz 4 mg, 4%; Toviaz 8 mg, 6%).” FAERS holds 10,773 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is dry mouth (823 reports).
- Generic listed
Check it at the source: the fesoterodine FDA label on DailyMed (effective April 7, 2026, Pfizer Laboratories Div Pfizer Inc); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of TOVIAZ?TOVIAZ may cause serious side effects, including: • serious allergic reactions. Symptoms of a serious allergic reaction may include swelling of the face, lips, throat, or tongue. If you have any of these symptoms, you should stop taking TOVIAZ and get emergency medical help right away. • inability to empty bladder (urinary retention). TOVIAZ may increase your chances of not being able to empty your bladder if you have bladder outlet obstruction. Tell your healthcare provider right away if you are unable to empty your bladder. • central nervous system (CNS) effects. Talk to your healthcare provider right away if you get any of these side effects: headache, dizziness, and drowsiness. • worsening of Myasthenia Gravis symptoms. […]
Source: FDA drug label, Pfizer Laboratories Div Pfizer Inc, effective April 7, 2026 (SPL set 5be745f0-8ae7-4c3c-9962-37d6263326f1), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost frequently reported adverse events with Toviaz in adult patients with OAB (≥4%) were: dry mouth (placebo, 7%; Toviaz 4 mg, 19%; Toviaz 8 mg, 35%) and constipation (placebo, 2%; Toviaz 4 mg, 4%; Toviaz 8 mg, 6%).
Table 4: Adverse Events With an Incidence Exceeding the Placebo Rate and Reported by ≥1% of Patients From Double-Blind, Placebo-Controlled Phase 3 Trials of 12-Weeks Treatment Duration
| System organ class/Preferred term | Placebo N=554 % | Toviaz 4 mg/day N=554 % | Toviaz 8 mg/day N=566 % |
|---|---|---|---|
| Dry mouth | 7.0 | 18.8 | 34.6 |
| Constipation | 2.0 | 4.2 | 6.0 |
| Dyspepsia | 0.5 | 1.6 | 2.3 |
| Nausea | 1.3 | 0.7 | 1.9 |
| Abdominal pain upper | 0.5 | 1.1 | 0.5 |
| Urinary tract infection | 3.1 | 3.2 | 4.2 |
| Upper respiratory tract infection | 2.2 | 2.5 | 1.8 |
| Dry eyes | 0 | 1.4 | 3.7 |
| Dysuria | 0.7 | 1.3 | 1.6 |
| Urinary retention | 0.2 | 1.1 | 1.4 |
| Cough | 0.5 | 1.6 | 0.9 |
| Dry throat | 0.4 | 0.9 | 2.3 |
| Edema peripheral | 0.7 | 0.7 | 1.2 |
| Back pain | 0.4 | 2.0 | 0.9 |
| Insomnia | 0.5 | 1.3 | 0.4 |
| ALT increased | 0.9 | 0.5 | 1.2 |
| GGT increased | 0.4 | 0.4 | 1.2 |
| Rash | 0.5 | 0.7 | 1.1 |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe following clinically significant adverse reactions are described elsewhere in labeling: • Angioedema [see Warnings and Precautions (5.1) ] • Urinary Retention [see Warnings and Precautions (5.2) ] • Decreased Gastrointestinal Motility [see Warnings and Precautions (5.3) ] • Most frequently reported adverse events with Toviaz in adult patients with OAB (≥4%) were: dry mouth (placebo, 7%; Toviaz 4 mg, 19%; Toviaz 8 mg, 35%) and constipation (placebo, 2%; Toviaz 4 mg, 4%; Toviaz 8 mg, 6%). ( 6.1 ) • Most frequently reported adverse reactions with Toviaz in pediatric patients (≥2%) with NDO were: diarrhea, urinary tract infection (UTI), dry mouth, constipation, abdominal pain, nausea, weight increased, and headache. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Pfizer Inc. at 1-800-438-1985 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Adult Overactive Bladder (OAB) The safety of Toviaz was evaluated in Phase 2 and 3 controlled trials in a total of 2859 patients with overactive bladder, of which 2288 were treated with Toviaz. …
Source: FDA drug label, Pfizer Laboratories Div Pfizer Inc, effective April 7, 2026 (SPL set 5be745f0-8ae7-4c3c-9962-37d6263326f1), via openFDA; the full label on DailyMed
What do FAERS reports show?
10,773 reports list fesoterodine among the medicines taken, each a report of something that happened, not proof the medicine caused it; 439 are coded as a death and 2,320 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 22 reactions below, 11 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Fesoterodine: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions