To the Editor: Recently 24 deaths have been reported in association with olanzapine-induced ketoacidosis. Koller and Doraiswamy (1) reported 23 deaths among 289 cases of hyperglycemia, and Meatherall and Younes (2) added another. We wish to report an additional case resulting in death.

This case, like most of the other 24 reported cases of fatal ketoacidosis associated with olanzapine, progressed to death within a relatively short time. Recently, Wilson et al. (3) reported five additional patients with nonfatal ketoacidosis, two of whom were taking olanzapine, two clozapine (augmented with risperidone in one case), and one quetiapine, thus raising the issue of whether ketoacidosis is also associated with other second-generation antipsychotics or combinations of medications. Alternatively, ketoacidosis may occur in genetically predisposed individuals, such as those with the polymorphism recently described as being associated with clozapine-induced weight gain (4). The fact that African Americans were disproportionately represented in previous reports (1, 3, 5) and an African American was involved in this case is consistent with that hypothesis.

It appears that hyperglycemia leading to ketoacidosis is an important side effect of olanzapine, and possibly other second-generation antipsychotics, and may have a fatal outcome. Its incidence is not known, but Wilson et al. (3) reported it as occurring in 4% (five of 126) of individuals treated with these antipsychotics. It is suggested that all individuals who start treatment with this drug, but especially African Americans, receive weekly monitoring of their blood sugar levels for the first 6 months.