propoxyphene and acetaminophen, Darvocet A500; Darvocet-N, Wygesic (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

Cholestyramine (Questran) reduces the effect of acetaminophen by decreasing its absorption into the body from the intestine. Therefore, acetaminophen should be administered 3 to 4 hours after cholestyramine or one hour before cholestyramine. Acetaminophen doses greater than 2275 mg per day may increase the blood thinning effect of warfarin (Coumadin) by an unknown mechanism. Therefore, prolonged administration or large doses of acetaminophen should be avoided during warfarin therapy.

PREGNANCY: There are no adequate studies in pregnant women.

NURSING MOTHERS: Low concentrations of propoxyphene have been measured in the breast milk of mothers taking propoxyphene. It is not known whether these small amounts can cause side effects in nursing infants.

SIDE EFFECTS: The most frequent adverse reactions of propoxyphene include lightheadedness, dizziness, sedation, nausea, and vomiting. Other side effects include drowsiness, constipation, and spasm of the ureter, which can lead to difficulty in urinating.

Propoxyphene can depress breathing and, therefore, is used with caution in elderly, debilitated patients, and in patients with serious lung disease. Propoxyphene can impair thinking and the physical abilities required for driving or operating machinery. Propoxyphene may be habit forming. Mental and physical dependence can occur but are unlikely when it is used short-term.

Reference: FDA Prescribing Information


Medically Reviewed by a Doctor on 7/15/2013


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