Background:Amphetamine derivatives have a great popularity among adolescents and young adults. Among such derivatives, a significant role is played by the recreational drug 3.4- methylenedioxy-methamphetamine (MDMA, Ecstasy). The correlation between the dose of ingested ecstasy and the severity-related symptoms in humans is poor; making it is difficult to predict its clinical outcome. Aim: to describe the profile of the designer drug users and summarize the clinical and toxicological information associated with its use in adolescents and young adults besides exploring its fatality over the course of two years for assessing its clinical course and outcome. Patients and Methods: an observational cross-sectional study was carried out on 59 patients from the emergency department in the complex for mental health in Riyadh from November 2010 to December 2012. Patients' blood was examined for MDMA by Immunoassay. The samples of the critical cases, which ended by death, were tested for drug concentration by liquid chromatography (LC/MS). Results: The mean patients' age was 21 years old, 77% of them were males. The prominent neuropsychiatric symptoms included coma with GCS score 3 (6.7%), speech impairment (16.9%), gait disorders (16.9%) and aggressiveness (23.7%). The prominent cardiac manifestations included pulse ≥100/min with GCS 3 (6.8%), systolic hypertension ≥100 (45.8%). Additionally, pupils were dilated in 6.8% and hyperthermia >39°C in 6.8%. Most of the patients make a full recovery, two patients out of the 59 patients (3.4%) had MDMA concentration of 1.63 mg/L and died after arrival, 5.4% needed intubation and ICU admission, and 18.2% were referred to psychiatric institutions. Conclusion: The recreational use of MDMA is highly dangerous. Studying the trend of adolescent drug use and the development of database would be very useful in the multidisciplinary approach of this public health issue.