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PP-Cap Side Effects

Generic name: propoxyphene

Note: This document contains side effect information about propoxyphene. Some dosage forms listed on this page may not apply to the brand name PP-Cap.

Applies to propoxyphene: oral capsule, oral tablet.


In general, the adverse effects of propoxyphene (the active ingredient contained in PP-Cap) may be more likely and more severe in patients with renal and/or liver disease.

General side effects including drug tolerance and influenza type illness have been reported.[Ref]

Nervous system

Nervous system side effects have included dizziness, sedation, stupor, delirium, somnolence, ataxia, coma, syncope, and respiratory depression. The sedative effects of propoxyphene (the active ingredient contained in PP-Cap) have been associated with a 60% increased risk of hip fracture in elderly patients.[Ref]


Other side effects have included dependence (although the abuse liability of propoxyphene (the active ingredient contained in PP-Cap) is less than that of some other narcotic analgesics). Withdrawal symptoms after either abrupt cessation or fast tapering may occur and include agitation, restlessness, anxiety, insomnia, tremor, tachycardia, hallucinations, psychosis, abdominal cramps, vomiting, sweating, and seizures.

Drug toxicity, multiple drug overdose, and narcotic overdose have also been reported.

Sensorineural deafness has been reported following chronic abuse and/or large doses of propoxyphene-containing compounds. Optic atrophy has been reported following overdose.[Ref]


Some of the cardiotoxic effects reported in association with propoxyphene (the active ingredient contained in PP-Cap) may be attributable to its major active metabolite, norpropoxyphene.[Ref]

Cardiovascular side effects have included arrhythmia, bradycardia, cardiac/respiratory arrest, congestive arrest, congestive heart failure (CHF), tachycardia, myocardial infarction (MI), hypotension, decreased blood pressure, elevated heart rate, abnormal heart rate, and dizziness. A variety of arrhythmias (including heart block) have been reported most often in association with propoxyphene overdose.[Ref]


A case of ischemic colitis has been reported following an overdose of propoxyphene (the active ingredient contained in PP-Cap) which was complicated by severe hypotension.[Ref]

Gastrointestinal side effects have included nausea, vomiting, and constipation which have been relatively common. Gastrointestinal bleeding and acute pancreatitis have also been reported.[Ref]


Genitourinary side effects including a case of retroperitoneal fibrosis have been reported.[Ref]


Dermatologic side effects including rashes and itch have been reported.[Ref]


Renal side effects have included a single case of nephrogenic diabetes insipidus following an overdose of propoxyphene (the active ingredient contained in PP-Cap) (however, other causes of diabetes insipidus in that patient were not rigorously excluded).[Ref]


Hepatic side effects have included elevated liver function tests, jaundice, hepatic steatosis, hepatomegaly, hepatocellular injury, and hepatotoxicity.[Ref]


Hematologic side effects have rarely included cases of hemolytic anemia, pancytopenia, and disseminated intravascular coagulation after administration (or abuse) of propoxyphene-containing compounds.[Ref]


Local side effects have included inadvertent intra-arterial injection with ensuing vascular compromise and distal necrosis has been reported in propoxyphene-abusing patients.[Ref]


Musculoskeletal side effects including myopathy and rhabdomyolysis have been reported after chronic oral use. Fibrous myopathy has also been reported in propoxyphene-abusing patients who administered the drug via intramuscular injection.[Ref]


Metabolic side effects including metabolic acidosis have been reported. Cases of severe hypoglycemia have been reported in patients with chronic renal failure.[Ref]


Ocular side effects including eye swelling and vision blurred have been reported.


Hypersensitivity side effects have been reported.[Ref]


Psychiatric side effects including abnormal behavior, confusional state, hallucinations, and mental status change have been reported.


Respiratory side effects including dyspnea have been reported.


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Further information

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

Some side effects may not be reported. You may report them to the FDA.