5 WARNINGS AND PRECAUTIONS
Angioedema of the face, lips, tongue, and/or larynx has been reported with fesoterodine. In some cases angioedema occurred after the first dose. Angioedema associated with upper airway swelling may be life-threatening. If involvement of the tongue, hypopharynx, or larynx occurs, fesoterodine should be promptly discontinued and appropriate therapy and/or measures to ensure a patent airway should be promptly provided.
5.2 Bladder Outlet Obstruction
Toviaz should be administered with caution to patients with clinically significant bladder outlet obstruction because of the risk of urinary retention [see Contraindications (4)].
5.3 Decreased Gastrointestinal Motility
Toviaz, like other antimuscarinic drugs, should be used with caution in patients with decreased gastrointestinal motility, such as those with severe constipation.
5.4 Controlled Narrow-Angle Glaucoma
Toviaz should be used with caution in patients being treated for narrow-angle glaucoma, and only where the potential benefits outweigh the risks [see Contraindications (4)].
5.5 Central Nervous System Effects
Toviaz is associated with anticholinergic central nervous system (CNS) effects [see Adverse Reactions (6.2)]. A variety of CNS anticholinergic effects have been reported, including headache, dizziness, and somnolence. Patients should be monitored for signs of anticholinergic CNS effects, particularly after beginning treatment or increasing the dose. Advise patients not to drive or operate heavy machinery until they know how Toviaz affects them. If a patient experiences anticholinergic CNS effects, dose reduction or drug discontinuation should be considered.
5.6 Hepatic Impairment
Toviaz has not been studied in patients with severe hepatic impairment and therefore is not recommended for use in this patient population [see Use in Specific Populations (8.7) and Dosage and Administration (2)].
5.7 Renal Impairment
5.8 Concomitant Administration with CYP3A4 Inhibitors
Doses of Toviaz greater than 4 mg are not recommended in patients taking a potent CYP3A4 inhibitor (e.g., ketoconazole, itraconazole, clarithromycin).
No dosing adjustments are recommended in the presence of moderate CYP3A4 inhibitors (e.g., erythromycin, fluconazole, diltiazem, verapamil and grapefruit juice).
While the effect of weak CYP3A4 inhibitors (e.g. cimetidine) was not examined by clinical study, some pharmacokinetic interaction is expected, albeit less than that observed with moderate CYP3A4 inhibitors [see Drug Interactions (7.2) and Dosage and Administration (2)].