Hair analysis to demonstrate administration of amitriptyline, temazepam, tramadol and dihydrocodeine to a child in a case of kidnap and false imprisonment

Amitriptyline, temazepam, tramadol and dihydrocodeine are prescription-only-medications that are rarely prescribed to children. Each of these drugs has a sedative effect on the central nervous system; their combined use could cause an exacerbation of the sedative effects. Amitriptyline (a tricyclic antidepressant) can be prescribed to treat nocturnal enuresis; temazepam (a hypnotic) can be used as a premedicant in inpatient and day-case surgery; tramadol (a synthetic opioid analgesic) is used to treat moderate or severe pain, though it is not recommended for children under the age of 12 years and dihydrocodeine (opioid analgesic), which is available in combination with acetaminophen (Co-dydramol®), is not recommended for children under the age of 4 years; in children over 4 years, a reduced dose is necessary. The North West Forensic Science Service Laboratory, Euxton, Lancashire, was asked by a British police force to analyze three separate hair samples, which had been collected from a young child following their discovery as a result of a large scale kidnap and false imprisonment investigation. After decontamination and segmentation (20 x 1-cm section), two of the three hair specimens were analyzed by liquid chromatography coupled with tandem mass spectrometry after alkaline (pH 9.5) extraction using methylene chloride/isopropanol/n-heptane (25:10:65, v/v/v). The entire length of each hair specimen tested positive for amitriptyline and nortriptyline (7–314 pg/mg amitriptyline; 7–318 pg/mg nortriptyline), temazepam (2–29 pg/mg), tramadol (60–2000 pg/mg) and dihydrocodeine (10–90 pg/mg) demonstrating that the child had ingested these drugs on more than one occasion prior to the kidnap. In this case, the child's mother and the mothers' partner were found guilty of kidnap, false imprisonment and perverting the course of justice. There are very few studies citing the concentrations of these drugs in children – especially children's hair samples. This case demonstrates the added value of hair testing and emphasizes the importance of using hair samples to complement conventional analysis.