Psychiatric Patients Increasingly Prescribed Multiple Medications

Over the past 50 years, there has been a significant rise in the number of psychiatric patients, including those with schizophrenia, receiving treatment with two or more antipsychotic medications simultaneously. This approach, known as antipsychotic polypharmacy, is generally discouraged by medical guidelines due to insufficient evidence of its effectiveness.

To gain updated insights, researchers from SDU and the Psychiatric Services in the Region of Southern Denmark analysed studies spanning from 1970 to 2023, examining the prevalence of antipsychotic polypharmacy—the concurrent use of multiple antipsychotic medications.

“Our findings reveal that patients undergoing antipsychotic polypharmacy tend to exhibit more severe symptoms and lower levels of functioning compared to those treated with a single medication. This could be a reflection of the greater severity of their illness, but it may also suggest that polypharmacy is not an optimal treatment approach,” says Mikkel Højlund, Associate Professor at SDU’s Department of Regional Health Research and the Mental Health Services in the Region of Southern Denmark.

The study encompassed nearly 4.5 million individuals over a span of 50 years.

The Consequences of Increased Medication Use

Despite recommendations against it, the use of antipsychotic polypharmacy in psychiatric treatment continues to rise. Polypharmacy is associated with greater illness severity, poorer outcomes, higher side-effect burden, and increased mortality. They have an increased risk for relapse, and worse quality of life.

"One in four psychiatric patients receives treatment with more than one antipsychotic medication, a practice that has grown increasingly common over the past five decades. This approach is not supported by clinical guidelines, as there is no evidence to suggest it leads to better outcomes. Instead, it is associated with higher dosages and a greater risk of side effects,” explains Mikkel Højlund.

The reasons for this trend remain unclear but may, for example, be attributed to transitional periods when patients are switched from one medication to another.

"Our study reveals important opportunities to enhance the treatment of schizophrenia. We are undertaking further research using Danish health registers to investigate potential links between polypharmacy and excess mortality, as well as to pinpoint specific areas where targeted interventions could make a meaningful impact," concludes Mikkel Højlund.