Darvocet A500 (100 mg propoxyphene napsylate and 500 mg acetaminophen)
The usual dosage is one tablet every 4 hours orally as needed for pain. The maximum dose of Darvocet A500 is 6 tablets per day. Do not exceed the maximum daily dose.
Patients receiving propoxyphene and any CYP3A4 inhibitor should be carefully monitored for an extended period of time and dosage adjustments should be made if warranted.
Consideration should be given to a reduced total daily dosage in elderly patients and in patients with hepatic or renal impairment.
Cessation of Therapy
For patients who used Darvocet A500 on a regular basis for a period of time, when therapy with Darvocet A500 is no longer needed for the treatment of their pain, it may be useful to gradually discontinue the Darvocet A500 over time to prevent the development of an opioid abstinence syndrome (narcotic withdrawal). In general, therapy can be decreased by 25% to 50% per day with careful monitoring for signs and symptoms of withdrawal (see DRUG ABUSE AND DEPENDENCE for description of the signs and symptoms of withdrawal). If the patient develops these signs or symptoms, the dose should be raised to the previous level and titrated down more slowly, either by increasing the interval between decreases, decreasing the amount of change in dose, or both.