Drugs of abuse in urine: some pitfalls in testing.

Drugs of abuse are usually detected in urine samples-drugs of abuse in urine (DAU). Whilst DAU testing may be required in the clinical situation, it is also a potential source of income from (e.g.) pre-employment medical examinations. DAU test results can, therefore, quite easily become the subject of legal debate. These points are discussed, along with an overview of the documentation procedures necessary should a laboratory decide to offer this service, and a brief survey of the screening and confirmatory testing procedures available.