BACKGROUND: A high smoking prevalence has been reported in treatment-seeking alcohol-dependent individuals. It has also been suggested that alcohol-dependent individuals who smoke may have a more severe course and greater severity of their alcoholism. METHODS: This study evaluated the impact of tobacco use in 108 Swedish male type 1 alcohol-dependent individuals, recruited by advertisement in a local daily newspaper. They were sub-grouped into smokers (N = 50), snuffers (N = 12) and tobacco nonusers (N = 46). The number of criteria for the diagnosis of alcohol dependence was used to assess the severity of alcohol dependence. RESULTS: The smokers were significantly younger compared to the tobacco non-using group, and also younger at their onset of excessive alcohol consumption. Both smokers and snuffers fulfilled significantly more DSM-IV criteria for alcohol dependence than tobacco nonusers. Furthermore, significantly higher proportions of smokers and snuffers fulfilled the criteria no 2 (experiencing withdrawal syndrome) and no 7 (continuing to use alcohol despite problems). CONCLUSIONS: These findings indicate that not only smoking, but also snuffing, is associated with greater severity of alcohol dependence, as reflected by the greater number of DSM-IV criteria.