Aims: To follow up on exchange students' alcohol use, drug use, mental health, self-rated health, and risky sexual behaviour after a semester abroad and to compare them with students who remained on campus. Methods: The study design was a follow-up study based on a previous baseline survey of 114 prospective exchange students and 451 campus students. Of the original 565 students, 48 (42.1%) prospective exchange students and 209 (43.3%) campus students responded to the follow-up. Both the baseline survey and the follow-up survey included the General Health Questionnaire 12, one single item from Self-Rated Health, and nine items from Knowledge, Attitudes and Sexual Behaviour in Young People in Sweden. Results: We found a statistically significant increase in the weekly consumption of alcohol among exchange students after their semester abroad. A larger proportion of exchange students had sex with a new partner and sex with more than three partners during their semester abroad compared to follow-up campus students. Conclusions: Our findings indicate that exchange students consume alcohol more frequently during their semester abroad and indulge in sexually risky behaviour. Exchange students' use of alcohol and sexually risky behaviour could be associated with even greater risks due to them being in an unknown environment, unfamiliar culture, and with limited support from family and friends. This highlights the need for further research on exchange students' experiences, especially concerning alcohol use and sex while abroad.