Introduction: Excessive daytime sleepiness (EDS) can interfere with academic and professional performance, as affected individuals tend to fall asleep in situations that demand a high level of alertness. Medical students are often a population at risk of suffering from EDS due to the demanding number of study hours, the significant number of credits per subject in the academic curriculum, practical teaching sessions and hospital night shifts, which can lead to sleep deprivation or sleep debt. It is for these reasons that it is important to estimate the prevalence of EDS and its associated factors in medical students of a Higher Education Institution (HEI) in Bucaramanga, in order to implement early prevention strategies to reduce the occurrence of this problem and to improve the students' quality of life and academic performance., Material and Methods: An observational, cross-sectional analytical study with a population sample of 458 medical students enrolled in the second semester of 2015 at the Universidad Autonoma de Bucaramanga (UNAB), who completed four questionnaires: Sociodemographic Variables, Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index and Sleep Hygiene Index (SHI). A bivariate and multivariate analysis was performed to identify any correlations with EDS., Results: Mean student age was 20.3 years and 62.88% of the 458 respondents were women. We were able to establish that 80.75% of participants suffered from EDS and 80.55% had a negative perception of their sleep quality (OR=1.91; 95% CI, 1.11-3.29; p =0.019]. In the multivariate analysis, it was found that the risk of EDS is lower in the clinical sciences than in the basic cycle. Furthermore, it was noted that a score higher than 15 in the Sleep Hygiene Index significantly increases the risk of suffering from EDS., Conclusions: Although EDS is very common in medical students, only a small percentage present the most severe form of this sleep disorder. Being enrolled in basic cycle subjects is associated with a higher risk of suffering EDS, so it is important for the curriculum committees of higher education institutions to regularly evaluate the number of hours of supervised and independent work performed by medical students. Finally, it is important to implement campaigns aimed at improving university students' perception of the risk of taking energy drinks and to establish sleep hygiene recommendations from the start of the academic programme., (Copyright © 2018 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España, S.L.U. All rights reserved.)