We studied the associations between comorbid anxiety and depressive disorders in treated alcoholics, the course of current anxiety and depression during the early and late post-detoxification periods, and drinking behaviours after discharge. Lifetime psychiatric comorbidity was assessed in 100 alcoholics using the Composite International Diagnostic Interview (CIDI). Three subgroups defined as group DA (comorbid depressive and anxiety disorders, n = 15), group A (anxiety disorder only, n = 23), and group NO (no comorbid disorder, n = 62) were studied. Beginning 21 +/- 13 days after cessation of drinking, state anxiety (STAI-X1), trait anxiety (STAI-X2) and depression (BDI) were assessed once per week (t1 to t4) and once more 6 months after discharge (t5, n = 68). The severity of psychopathology decreased during the first 4 weeks after detoxification in all subgroups. However, trait anxiety remained at higher levels in both the comorbid subgroups from t1 to t4. In the follow-up sample, 60.5% of the non-comorbid subjects remained abstinent, but only 26.7% of all comorbid patients and only 12.5% of those with comorbid depressive disorder plus severe current trait anxiety or depression at t1. Independent of their comorbidity status, relapsers at t5 had already reported more trait anxiety than abstainers at t1. We conclude that severe trait anxiety persisting after 3 weeks of abstinence, comorbid depressive and/or anxiety disorders, and combinations of these with moderate or severe current anxiety and depressive states represent the greatest risks of relapse and therefore may indicate a treatment need.