[01] Sowmiya Rajeswaran, Faculty of Medicine, Melaka Manipal Medical College, Manipal Academy of Higher Education (MAHE), Melaka, Malaysia. [02] Muhammad Zulkhairie Bin Zulkifli, Faculty of Medicine, Melaka Manipal Medical College, Manipal Academy of Higher Education (MAHE), Melaka, Malaysia. [03] Nurul Atasya Binti Budi Irawan, Faculty of Medicine, Melaka Manipal Medical College, Manipal Academy of Higher Education (MAHE), Melaka, Malaysia. [04] Norarina Binti Mohd Seh, Faculty of Medicine, Melaka Manipal Medical College, Manipal Academy of Higher Education (MAHE), Melaka, Malaysia. [05] Lee Ser Yin, Faculty of Medicine, Melaka Manipal Medical College, Manipal Academy of Higher Education (MAHE), Melaka, Malaysia.

Caffeine is the most commonly consumed psychoactive substance in the world and not only found in coffee, but also present in other products that includes tea, energy drinks, caffeine containing medicine and soft drink. The aim of conducting the research is to study caffeine expectancy with gender, ethnicity, type of caffeinated products and frequency based on dependence/ withdrawal, work enhancement, appetite suppression, mood enhancement, physical performance, negative physical effect and also on sleep disturbance. A cross sectional study was conducted from October to December 2019 in our college. Purposive sampling was used to enroll students for this study and they were asked to respond to the validated questionnaires on a Liker scale. A questionnaire related to the caffeine expectancy was used in this study. Each of the question represents a domain that we can elicit based on the expectancy towards caffeine consumption which are dependence/withdrawal, physical enhancement, mood enhancement, appetite suppression, negative effect, sleep disturbance and work enhancement. The analysis included frequency, percentages, mean, standard deviation, unpaired T-test and ANOVA. A total of 127 participated in this study; we find that 70.9% of medical student consumed caffeine in the form of tea, 68.5% in the form of coffee and 43.3% in form of soft drinks or energy drinks. Most of the medical student aware and expect the positive effect towards caffeine consumption but less awareness on its negative side effect such as appetite suppression and dependence/withdrawal. But for the sleep disturbance, most of them are fully aware about this effect and that’s is the most reason they consume caffeine in the night so that they can study effectively. Based on gender, there is no different on the expectancy towards caffeine consumption between female and male. But according to ethnicity, there is different on how they expect towards caffeine consumption; where Chinese has the least expectancy on work enhancement after consume caffeine while Malay and Indian has the least expectancy on negative effect after caffeine consumption. Most of the medical students that consume the caffeinated products believed that by consuming caffeine will increase the productivity. Students believes that caffeine can make them more alert, more energetic, and even improves their concentration, attention and motivation towards work. Future research should explore the association between caffeine dose with the caffeine expectancy. Study on psychometric assessment such as stress and anxiety can be conducted along with caffeine expectancy.

Caffeine, Cross-sectional, Medical Students

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