Postmortem drug levels: innocent bystander or guilty as charged

Determining the etiology or cause of an event in forensic cases often creates many theories. On piece of additional information which may be helpful in cases involving a drug or medication are concentrations or serum levels. Although many confounders can affect the interpretation of the drug level, it is imperative to also relate the data to the clinical scenario presented. Drug levels can be highly variable, depending on the time drawn, location from where the sample was obtained, and reference/references utilized in its interpretation. Postmortem drugs levels often do not reflect the blood levels before death. A drug level can be elevated exclusively because of postmortem distribution. This may result in a conclusion of a poisoning as the cause of death when in fact the death resulted from nonpharmacologic or nontoxicologic causes. Caution is advised from making any conclusions based solely on the drug level; rather an in-depth review of the clinical scenario, reference literature, and drug characteristics are required.