Two cases of patients with a severe comorbidity of alcohol abuse treated with topiramate are reported. The first case is a 52-year-old patient who has been suffering from schizophrenia for many years. Topiramate prescription was associated with a discontinuation of his chronic, refractory alcohol consumption. The second case is a 41-year-old patient with bipolar disorder that mainly manifests itself through manic episodes. Topiramate treatment allowed him to decrease his alcohol intake to an acceptable level. Consequently, his bipolar symptoms also improved, without the appearance of any side effects. Thus, topiramate may improve alcohol intake among patients with schizophrenia or bipolar disorder. Certain studies have shown the efficacy of topiramate in alcoholic patients without such associated disorders, but further research is needed for this special population.