Sorry, you need to enable JavaScript to visit this website.

DETROL® LA (tolterodine tartrate) Drug Interactions

7 DRUG INTERACTIONS

7.1 Potent CYP2D6 Inhibitors

Fluoxetine, a potent inhibitor of CYP2D6 activity, significantly inhibited the metabolism of tolterodine immediate release in CYP2D6 extensive metabolizers, resulting in a 4.8-fold increase in tolterodine AUC. There was a 52% decrease in Cmax and a 20% decrease in AUC of 5-hydroxymethyl tolterodine (5-HMT), the pharmacologically active metabolite of tolterodine [see CLINICAL PHARMACOLOGY (12.1)]. The sums of unbound serum concentrations of tolterodine and 5-HMT are only 25% higher during the interaction. No dose adjustment is required when tolterodine and fluoxetine are co-administered [see CLINICAL PHARMACOLOGY (12.3)].

7.2 Potent CYP3A4 Inhibitors

Ketoconazole (200 mg daily), a potent CYP3A4 inhibitor, increased the mean Cmax and AUC of tolterodine by 2- and 2.5-fold, respectively, in CYP2D6 poor metabolizers.

For patients receiving ketoconazole or other potent CYP3A4 inhibitors such as itraconazole, clarithromycin, or ritonavir, the recommended dose of DETROL LA is 2 mg once daily [see DOSAGE AND ADMINISTRATION(2.2) and CLINICAL PHARMACOLOGY (12.3)].

7.3 Other Interactions

No clinically relevant interactions have been observed when tolterodine was co-administered with warfarin, with a combined oral contraceptive drug containing ethinyl estradiol and levonorgestrel, or with diuretics [see CLINICAL PHARMACOLOGY (12.3)].

7.4 Other Drugs Metabolized by Cytochrome P450 Isoenzymes

In vivo drug-interaction data show that tolterodine immediate release does not result in clinically relevant inhibition of CYP1A2, 2D6, 2C9, 2C19, or 3A4 as evidenced by lack of influence on the marker drugs caffeine, debrisoquine, S-warfarin, and omeprazole [see CLINICAL PHARMACOLOGY (12.3)].

7.5 Drug-Laboratory-Test Interactions

Interactions between tolterodine and laboratory tests have not been studied.

7.6 Other Anticholinergics

The concomitant use of DETROL LA with other anticholinergic (antimuscarinic) agents may increase the frequency and/or severity of dry mouth, constipation, blurred vision, somnolence, and other anticholinergic pharmacological effects.

What's New

No Current Announcements.

Contact Pfizer Medical

Report an Adverse Event
1-800-438-1985

Search

Please enter your search term(s) for DETROL® LA

Contact Pfizer

Need to report an Adverse Event, Side Effect or Product Quality Concern?

Contact Pfizer Safety to report an adverse event, side effect or concern about the quality of a Pfizer product: (800) 438-1985

You may also contact the U.S. Food and Drug Administration (FDA) directly to report adverse events or product quality concerns at 1-800-FDA-1088 or www.fda.gov/MedWatch

Have a Medical Question on a Pfizer Prescription Medicine?
Contact Pfizer Medical Information to speak with a professional regarding your medical question on a Pfizer prescription product: (800) 438-1985
Have a Question on a Pfizer Over-the-Counter Product?
For Pfizer Consumer Healthcare non-prescription or over-the-counter products such as Advil, Centrum, Nexium or Thermacare, call (800) 322-3129
Have a Question about Pfizer Clinical Trials?
If you are looking for information about Pfizer studies currently recruiting new patients in your area, you can begin your search on our website. For questions about a Pfizer Clinical Trial, call (800) 718-1021 or email [email protected]
Need Information on Pfizer’s Patient Assistance Programs?

Pfizer RxPathways® connects eligible patients, regardless of their insurance status, to a range of assistance programs that offer insurance support, co-pay help, and medicines for free or at a savings. For more information, please call (844) 989-7284 or visit www.PfizerRxPathways.com.

Eligible patients can register for valuable savings offers for nearly 40 brand name medications. Visit www.MyPfizerBrands.com for more information.