Propoxyphene overdosage: a study of cases involving analgesic preparations containing dextropropoxyphene

Overdose of Dologesic with a Fatal Outcome: A Case Report

Dologesic is a commonly prescribed analgesic in accident and emergency department. Yet report of overdose with this drug is not common. We report a case in which the patient developed cardiac arrest within an hour of ingestion. Dextropropoxyphene, a component of the drug Dologesic, used to be a common cause of fatalities after drug overdose in the seventies. It is highly toxic in overdose and therefore caution should be exercised when prescribing this drug.

Deaths from paracetamol and dextropropoxyphene (Distalgesic) poisoning in England and Wales in 1979

Paracetamol and dextropropoxyphene were implicated on clinical and analytical grounds in 237 poison deaths in England and Wales in 1979. In addition to paracetamol, dextropropoxyphene and ethanol, other agents were detected in 61 of these cases (26%). Analytical evidence suggests that very substantial overdoses of paracetamol and dextropropoxyphene were ingested in the majority of cases; their mean plasma concentrations in those ingesting no other agents were 252 and 8.64 mg/l respectively. Significant quantities of ethanol were ingested in 133 of 237 cases (56%). The mean ethanol concentration in those in whom quantitative estimations of paracetamol, dextropropoxyphene and ethanol were undertaken and who had not ingested other drugs, was 1588 mg/l. There was no analytical support for the diagnosis of paracetamol and dextropropoxyphene poisoning in 74 of 305 cases (24%) of H.M. Coroners' returns to the Office of Population, Censuses and Surveys for the period 1 January-31 December 1979. In addition, dextropropoxyphene was detected analytically in six cases classified as being due to paracetamol alone.

Dextropropoxyphene poisoning: problems with interpretation of analytical data

Difficulties in the estimation and interpretation of dextropropoxyphene and norpropoxyphene analyses have added to the controversy concerning the toxicity of these compounds. Poor performance in external proficiency assessment trials reflects the unsatisfactory state of many dextropropoxyphene and norpropoxyphene analyses in general use. There is substantial overlap between blood concentrations of dextropropoxyphene and norpropoxyphene encountered in chronic therapeutic dose and those associated with acute toxicity. As dextropropoxyphene and norpropoxyphene are often taken in overdose with other drugs, their blood concentrations must be interpreted in the context of careful identification and quantitation of such agents. The present availability of accurate methods for measurement of parent drug and metabolite should now make anecdotal reports unsupported by analytical data entirely superfluous.

Fatal self-poisoning in the UK and the paracetamol/dextropropoxyphene combination

Coroners' files have been examined to ascertain the numbers of deaths involving self-poisoning with analgesic drugs with specific reference to the paracetamol/dextropropoxyphene combination. The period of study was 1976-1980. This report concentrates on cases in England, although reference is made to similar deaths occurring in Scotland and Northern Ireland. Data have been collected extensively on a wide range of issues concerning fatal self-poisonings mainly by visiting coroners' offices in England to make direct investigation of records. The total number of cases where the paracetamol/dextropropoxyphene combination can be considered as ingested in the self-poisoning episode is underestimated. The number of cases involving alcohol and/or other drugs taken together with the combination product is particularly underestimated. Involvement of people aged 30 years and below comprises 32% of all cases. 'Gesture' overdoses comprise an estimated 14% of all cases in England. An analysis of fatalities from cases where quantities in post-mortem blood of dextropropoxyphene less than 1 microgram/ml and paracetamol less than 50 micrograms/ml are found and of cases where death occurs within 2 h of ingestion of the overdose has been carried out. The results are inconclusive. In most cases alcohol and/or other drugs are found to be involved. Critical inspection of coroners' files shows relatively few of these cases where the combination product is ingested on its own. There is wide variability in the data available in coroners' files. In many cases data of value to this research are not recorded. Medical history and quantitative levels of drugs suspected (particularly dextropropoxyphene) are particular examples of factors which may not be recorded. Office of Population, Censuses and Surveys (OPCS) mortality data are based on certified causes of death. Because of the underestimate of the involvement of this combination product and the under-reporting of other drug and/or alcohol ingestion with the combination, care must be exercised in quoting or drawing conclusions from OPCS statistics.