Background: Offenders performing drug-facilitated crime (DFC) generally choose their drug based on its availability and their own attitude. Prevalence of DFC has increased in our society triggering some public concerns. Treatment of the patients strongly depends on the abused drug while the type of the drug involved is generally unknown; hence, we performed a study to determine the most frequently abused drugs to facilitate crimes in Iran. Methods: In a prospective study, all patients who were referred to our medical toxicology ward due to DFC between February 2009 and March 2010 were included. A self-made questionnaire was filled out for each patient. Urine samples were taken on presentation, and drugs were extracted by organic solvents using liquid-liquid extraction (LLE) method. Forensic toxicology urine analyses were performed using immunochromatography and thin layer chromatography (TLC) as screening tests. High-performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS) were used as confirmatory methods. Results: In 53 patients, 8 (15.1%) were female and the mean age was 31.6 ± 12.5 years. They were mainly poisoned to facilitate theft (77.4%). Drugs were commonly given in drinks (45.3%) and during transportations (45.4%). The patients had usually been referred with mild loss of consciousness (56.6%), and the most common drugs given were metoclopramide and dextromethorphan (18.9%). No death was documented, and the mean hospitalization period was 1 day. Conclusion: Opioids are the most commonly involved drugs in DFCs in Iran. Metoclopramide, benzodiazepines, and antihistamines are other common drugs used for this purpose. Public health education, training, and empowerment of medical staff dealing with investigating and management of DFC are required.