Coumadin and Tolterodine Extended-Release Capsules

In the database of official manuals used in the service creation an interaction registered by statistical results of studies was found, which can either lead to negative consequences for the patient health or strengthen a mutual positive effect. A doctor should be consulted to address the issue of joint drug administration.

Using warfarin together with tolterodine may cause you to bleed more easily. You may need a dose adjustment based on your prothrombin time or International Normalized Ratio (INR). Call your doctor promptly if you have any unusual bleeding or bruising, vomiting, blood in your urine or stools, headache, dizziness, or weakness. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

MONITOR: Limited clinical data suggest that tolterodine may potentiate the hypoprothrombinemic effect of warfarin in some patients. There have been case reports of patients stabilized on warfarin whose INR increased following the addition of tolterodine and returned to normal after discontinuation of tolterodine, temporary withholding of warfarin doses, or reduction of warfarin dosage. The mechanism is unknown. In 20 healthy volunteers, pretreatment with tolterodine (2 mg orally twice a day for 7 days) relative to placebo had no significant effect on the pharmacokinetics of R(+) and S(-) warfarin or prothrombin times and factor VII activity following a single 25 mg dose of warfarin administered on study day 4. Warfarin also had no effect on the pharmacokinetics of tolterodine or its pharmacologically active 5-hydroxymethyl metabolite.

MANAGEMENT: Given the potential for interaction and the high degree of interpatient variability with respect to warfarin metabolism, patients should be closely monitored during concomitant therapy with tolterodine. The INR should be checked frequently and warfarin dosage adjusted accordingly, particularly following initiation, discontinuation or change of dosage of tolterodine in patients who are stabilized on their warfarin regimen. The same precaution may be applicable during therapy with other oral anticoagulants, although clinical data are lacking. Patients should be advised to promptly report any signs of bleeding to their physician, including pain, swelling, headache, dizziness, weakness, prolonged bleeding from cuts, increased menstrual flow, vaginal bleeding, nosebleeds, bleeding of gums from brushing, unusual bleeding or bruising, red or brown urine, or red or black stools.

Coumadin

Generic Name: warfarin

Brand name: Coumadin, Jantoven

Synonyms: n.a.

What is Coumadin?

Tolterodine Extended-Release Capsules

Generic Name: tolterodine

Brand name: Detrol, Detrol LA

Synonyms: Tolterodine

What is Tolterodine Extended-Release Capsules?