There is insufficient evidence to recommend for or against routine screening for drug abuse with standardized questionnaires or biologic assays. Including questions about drug use and drug-related problems when taking a history from all adolescent and adult patients may be recommended on other grounds (see Clinical Intervention). All pregnant women should be advised of the potential adverse effects of drug use on the development of the fetus. Clinicians should be alert to signs and symptoms of drug abuse in patients and refer drug abusing patients to specialized treatment facilities where available.