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Acetaminophen / Propoxyphene Dosage

Applies to the following strengths: napsylate 325 mg-50 mg; napsylate 650 mg-100 mg; hydrochloride 650 mg-65 mg; napsylate 325 mg-100 mg; napsylate 500 mg-100 mg

Usual Adult Dose for:

Additional dosage information:

Usual Adult Dose for Pain

Acetaminophen-propoxyphene was voluntarily withdrawn from the US market by the manufacturer in November 2010 due to new data showing that the propoxyphene component can cause serious toxicity to the heart, even when used at therapeutic doses. The following dosage information applied to when ASA/caffeine/propoxyphene was available in the US:

1 to 2 tablets (acetaminophen 325 mg/propoxyphene 50 mg) or
1 tablet (acetaminophen 325 mg/propoxyphene 100 mg)
1 tablet (acetaminophen 650 mg/propoxyphene 100 mg) or
1 tablet (acetaminophen 650 mg/propoxyphene 65 mg) or
1 tablet (acetaminophen 500 mg/propoxyphene 100 mg)
orally every 4 hours as needed.

The maximum recommended dose of propoxyphene napsylate is 600 mg/day and of propoxyphene HCl is 390 mg/day.

Renal Dose Adjustments

Mild Renal Dysfunction: One acetaminophen-propoxyphene hydrochloride (650 mg-65 mg) or one acetaminophen-propoxyphene napsylate (325 mg-50 mg) tablet orally every six hours as necessary.

Severe Renal Dysfunction: Because the elimination of propoxyphene and its cardiotoxic metabolite, norpropoxyphene, is significantly impaired in patients with severe renal dysfunction, the use of acetaminophen-propoxyphene is not recommended.

Liver Dose Adjustments

Acetaminophen-propoxyphene should be used with great caution, if at all, in patients with liver disease. However, if more appropriate alternatives are not available and acetaminophen-propoxyphene must be used, the initial suggested dosage is acetaminophen-propoxyphene napsylate (325 mg-50 mg) 1 tablet orally once. The use of multiple doses of acetaminophen-propoxyphene napsylate is not recommended due to the risk of accumulation of propoxyphene in the presence of liver disease. For patients with hepatic failure, the use of acetaminophen-propoxyphene is not recommended.

Dose Adjustments

Doses should be titrated to appropriate analgesic effect with consideration of severity of pain and patient size.

If a patient is on prolonged therapy, then discontinuation should be gradual. Acetaminophen and propoxyphene should be reduced by 25% to 50% daily and the patient should be carefully monitored for signs/symptoms of withdrawal.

Precautions

Consideration should be given to a reduced total daily dosage in patients with hepatic or renal impairment.

Dialysis

Propoxyphene is not dialyzable.

Because the elimination of propoxyphene and its cardiotoxic metabolite, norpropoxyphene, is significantly impaired in patients with severe renal dysfunction, the use of acetaminophen-propoxyphene is not recommended.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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