This simple observational series illuminates the likely truths behind our anecdotal experience – patients are either clueless or deliberately misleading regarding their ingestion of foreign substances.
For the purposes of this investigation, “drug use” is not restricted to illicit substances – these authors also explored the reliability of reporting of prescription medications. In this prospective, year-long enrollment, 55 patients were selected randomly from a larger cohort to have a urine sample submitted for liquid chromatography/mass spectrometry. The LC/MS assay utilized was capable of detecting 142 prescriptions, over-the-counter drugs, and drugs of abuse and their metabolites. A drug whose level of detection was lower than 2 half-lives was reported as discordant with patient self-reporting.
All told, 17 out of 55 patients provided accurate medication histories, based on those detected on LC/MS. Over half the patients under-reported – including a patient with 7 unreported drugs detected – while 29% over-reported a drug not subsequently detected. Interestingly, illicit drugs were the least likely to be mis-reported, although, that may simply be a reflection of the higher prevalence of prescription and OTC medications.
Such observations are limited by the accuracy of the assay utilized, which has not been validated. However, it ought come as no surprise many patients either intentionally or unintentionally misrepresent all possible drug exposures. While not all omissions are clinically relevant, certainly, non-compliance and misinformation may have important implications for diagnosis and treatment.
“The Accuracy of Self-Reported Drug Ingestion Histories in Emergency Department Patients”
http://www.ncbi.nlm.nih.gov/pubmed/25052325