Self-medication, the practice of using medications without professional guidance, is a significant public health concern globally, particularly among medical students who, despite their pharmacological training, often engage in this practice at high rates. This cross-sectional study aimed to assess the prevalence and patterns of self-medication among medical students at the University of Tripoli, Libya. A sample of 121 undergraduate medical students was surveyed using a semi-structured questionnaire. The results revealed a high prevalence of self-medication (82.6%), with analgesics (51.2%) and vitamins (31.4%) being the most commonly used medications. Headache (80.4%), pain (79.9%), and respiratory issues (73.2%) were the primary health complaints prompting self-medication. Key determinants included pharmacist advice (43.8%), prior medical knowledge (32.2%), and recommendations from family or friends (12.4%). Factors such as residing in Tripoli and higher parental education levels were significantly associated with increased self-medication practices. Notably, 62.0% of the students reported using antibiotics without a prescription, raising concerns about antimicrobial resistance. The study highlights the need for educational interventions to promote responsible self-medication practices among medical students, emphasizing the risks associated with inappropriate drug use. Addressing these issues early in medical education could help mitigate the public health implications of widespread self-medication.