Abstract
Background: Due to advances in technology, the range of specimens that can be used to investigate a person's drug status has widened. Traditionally, urine was the specimen of choice, but increasingly oral fluid and hair are being used. This review discusses the advantages and disadvantages of the three specimens—urine, oral fluid and hair.
Methods: The literature was searched for the latest information concerning the two newer specimens, oral fluid and hair. The review includes the practical problems and disadvantages associated with each specimen, which are not usually documented.
Results: The major advantage of using urine for analysis is that the methods used are well established, but there are major problems with substitution/adulteration; the major advantage of using oral fluid is that specimen collection can be observed without privacy issues, but the drawbacks are the relatively shorter window of detection, the sensitivity of immunoassay kits especially to cannabinoids and benzodiazepines, and the lack of literature concerning dose and oral fluid drug concentration. The major advantage of hair is the long window of detection, but there are no on‐site testing kits available, the samples have to be sent to a specialized laboratory.
Conclusion: Although the time window of the drug history is a consideration when determining which specimen to use for verifying drug status, the pros and cons of each specimen also need to be fully considered.