Introduction: Psychiatric medication use has increased recently among college students. This includes antidepressants, opioids, stimulants, analgesics, sedatives, and anxiolytics, which could be self-administered without medical supervision. Objectives: To determine the prevalence of medical and nonmedical use of psychiatric prescription medications and its correlation with academic performance, demographic data as well as the motives for the nonmedical use. Methods: A cross-sectional study aims to assess the psychiatric medication use with or without prescription with the motives behind it, and demographic data of the students at medical colleges in Riyadh, Saudi Arabia. Results: A total of 1268 responded to the questionnaire. 251 (20%) of the participants reported using some psychiatric medications in their lifetime, while 191 (15%) participants used some psychiatric medications in the last 12 months. Antidepressants were most used in the surveyed population 144 (57%), followed by opioids/pain relief medications 62 (24%) and anxiolytics 39 (15%). Only 44 surveyed students (3.5%) reported nonmedical use of these psychiatric medications. As for the motives of nonmedical use, the greatest portion reported to use it for “relax or relieve tension” 12 (29%), followed by “relieve pain caused by other health problems” 8 (20%), and “medication to get through the day” 6 (15%). Conclusion: Nonmedical use of psychiatric medications among medical students in Riyadh is several times lower than reports by other researchers. Future research should focus on collecting more participants who are using medications without prescription and conduct cross-cultural studies to examine factors contributing to such low rates of illicit psychiatric medication use.