Toxicological investigations of cases of death involving codeine and dihydrocodeine

Fatal blood and tissue concentrations of more than 200 drugs

Fatal drug concentrations in body fluids and tissue samples are presented for more than 200 drugs and chemicals of toxicologic interest. Additionally, a reference list is added with more than 600 original papers concerning intoxications with a lethal outcome. The data can be helpful for the interpretation and plausibility control in own cases of intoxication. However, they should be used with caution, because use of drug data without sufficient knowledge about the patient or victim, the circumstances of the case, and about toxicokinetics and toxicodynamics might give a wrong interpretation in a special case.

The role of dihydrocodeine in causing death among drug users in the west of Scotland

There has been a wealth of information relating to the role of methadone in fatalities over the past decade. However, a dearth exists in the literature of deaths involving dihydrocodeine, a substitute that is being increasingly prescribed by general practitioners for drug harm reduction purposes. Over the past five years in the Strathclyde region of Scotland there has been an increase in the number of drug related deaths involving dihydrocodeine with the largest increase occurring in the latter two years. This in combination with a general acceptance for this drug as a substitute for methadone amongst general practitioners highlights its potential abuse factor which is addressed in this paper. As the number of methadone deaths in relation to the total number of accidental drug related deaths per annum decrease, those related to dihydrocodeine are shown to be increasing.

Formation and clearance of active and inactive metabolites of opiates in humans

The results of recent investigations of the analgesic and the nonanalgesic effects of opioid glucuronides are relevant to the research on drug abuse in forensic toxicology. As has been shown for heroin, knowledge of the state of distribution and elimination of active and inactive metabolites and glucuronides offers new possibilities in forensic interpretation of analytic results. Because of similar metabolic degradation, calculation of the time-dependent ratio of the concentration of morphine and its glucuronide metabolites in blood or serum allows a rough estimation of increased dosage and of time elapsed since the last application. Drug effects can be examined with respect to individual case histories, including overdose and survival time if the patient died. However, different methods of administration and the strong influence of different volumes or compartments of distribution of parent compounds and metabolites on concentrations in human body tissues require careful use of glucuronide concentration data. In Germany, dihydrocodeine (DHC) is prescribed as a heroin substitute, and relative overdoses are needed to be effective. DHC metabolism was studied in three patients who died from overdoses. All metabolites (dihydrocodeine-6-glucuronide [DHC6], nor-DHC [NDHC], dihydromorphine [DHM], nor-DHM [NDHM], and DHM-3- and 6-glucuronide [DHM3G, DHM6G]) were determined using HPLC and fluorescence detection. Concentrations of DHM (0.16 mg/L to 0.22 mg/L serum) were found. The DHM glucuronide ratios were similar to those of morphine. Receptor binding studies showed that the binding affinity of DHM to porcine mu-receptor was higher than that of morphine, and DHM6G's binding affinity was as high as that of morphine-6-glucuronide (M6G). Metabolites may play an important role in the effectiveness of DHC in substitution and toxicity. Because of enzyme polymorphism, the formation of DHC poses a risk for proper dosage in patients who are either poor or extensive metabolizers. The distribution of opioid glucuronides in cerebral spinal fluid in relation to transcellular transport in central nervous tissue is discussed with respect to the receptor binding of opiates and drug effect.

Postmortem distribution of dihydrocodeine and metabolites in a fatal case of dihydrocodeine intoxication

A report of a fatal dihydrocodeine ingestion under substitution therapy is given. Quantitation of dihydrocodeine, dihydromorphine, N-nordihydrocodeine, dihydrocodeine-6-, dihydromorphine-6- and dihydromorphine-3-glucuronide was performed simultaneously after solid-phase extraction prior to HPLC analysis, and the analytes were detected using their native fluorescence. Postmortem concentrations of blood samples from different sampling sites as well as from liver, kidney and cerebrum are reported. A hair sample was investigated to prove long-term use of the substitute drug. Site-to-site differences of the analytes from blood samples were very small. The partition behavior of the opioid glucuronides depended on the hematocrit value of the particular blood sample. Most important findings seemed that dihydromorphine and dihydromorphine-6-glucuronide concentrations decisively contributed to the toxicity of dihydrocodeine. This case report outlines that in dihydrocodeine related deaths the concentrations of the pharmacologically active metabolites should additionally be determined for reliable interpretation.

Codeine concentrations in human samples in a case of fatal ingestion

Capillary gas chromatography coupled to mass spectrometry was employed to quantify codeine in biological fluids and tissues in a death attributed to oral codeine ingestion. The blood concentration of codeine was 22.1 mg/l. Results are discussed in the light of the existing literature.

Sudden death after minor abdominal trauma: an unusual presentation of phaeochromocytoma

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Drug levels found in cases of fatal self-poisoning

A list of drug levels found in cases of fatal self-poisoning is presented here. These are all cases where only one drug was found and the cause of death in each case was attributed to an overdose of that particular drug. For each case a full drug screen was carried out. In general thin-layer chromatography (TLC) was used as the initial screening technique and any positive findings were then confirmed by gas liquid chromatography (GLC) and high performance liquid chromatography (HPLC). When the drug had been positively identified, the blood level was measured.

The human distribution of some barbiturate sedatives in combination with miscellaneous CNS-active drugs

This paper presents 14 cases in which the distribution of barbiturates and the hydroxylated metabolites in combination with miscellaneous CNS-active drugs was studied. In 7 of these cases the other drug present was methadone, and in the remainder dihydrocodeine, morphine, propoxyphene, amitriptyline, meprobamate, cyclizine and dipipanone, diphenhydramine and methaqualine. Amitriptyline, methadone, cyclizine and dipipanone, methaqualone and diphenhydramine appeared to modify the distribution of amylorbarbitone and quinalbarbitone. Likewise, the barbituates seemed to alter the distribution of amitriptyline, propoxyphene and, in one instance, methadone.