Alternative and “off-label” uses of antipsychotic medications in Medicaid

Despite the terminology, antipsychotics are used for disorders other than psychosis, especially severe mood disorders, and including non-FDA approved indications. This work used Medicaid administrative data from a single state and year (7/2000 to 6/2001) to estimate rates of alternative uses for antipsychotics. This year is the baseline for a four year longitudinal follow-up of antipsychotic effectiveness. An indicator of alternative antipsychotic use will be used to create covariates of drug choice for that study. Here we report on alternative use by mental health diagnoses. All unique Medicaid clients with at least one antipsychotic prescription and no record of schizophrenia (n=16,337) were considered. A subset (n=4,237) of those treated by ‘experience providers'- defined as a providers treating at least 20 patients with schizophrenia in the year- were also considered. For the complete sample, diagnoses observed in over 5% of the population were: episodic mood (35%), dementia (16%), depression, nos (16%), anxiety, dissociative and somatoform (14%), persistent mental disorders due to other conditions (11%), other non-organic psychoses (9%), and mental retardation (8%). For clients treated by the ‘experienced providers', these rates were comparable, but intensified toward mood disorders: 69%, 10%, 28%, 24%, 8%, 15%, and 10%, respectively. Among the clients having contact with ‘experienced providers' the following other diagnoses were also prevalent across their Medicaid records: conduct disorder, nos (9%) and adjustment reaction (8%). These results are consistent with substantial alternative use of antipsychotics especially for mood disorders. They also suggest distinctive patterns for the most experienced mental health care providers.