The risks associated with alcohol intoxication are rarely discussed during pre-travel counselling. However, alcohol immoderation abroad may increase the exposure to health risks. Few studies have addressed alcohol consumption and risk taking behaviour in travellers to South America. From October to December of 2004, travellers leaving the city of Cusco in Peru were asked to fill out anonymous questionnaires regarding demographics, self-reported alcohol consumption, illness and risk behaviour for sexually-transmitted infection (STI) and travellers diarrhoea. Most travellers (87.2%) consumed alcohol and 20.4% reported inebriation in Cusco. Those admitting inebriation were more likely to be male, single, <26 years old, and travelling alone or with friends. Travellers who admitted inebriation and fell ill while in Cusco were more likely to seek medical attention, change itinerary, and report decreased satisfaction with the trip experience. In the multivariate analysis, inebriation was independently associated with reporting higher numbers of unsafe food choices, illicit drug use, and risky sexual activity. It is concluded that alcohol intoxication during travel was associated with increased risk taking behaviour for common travel related conditions. Although travel related illnesses were not associated with inebriation, some markers of illness severity were more often reported by those who admitted intoxication. Risk for heavy alcohol use abroad should be assessed during the pre-travel visit in certain groups and appropriate counselling should be provided.