Future Spending for Prescription Drugs Used for Mental Health and Substance Use Disorders: Does the Past Portend the Future?

Prescription drug expenditures on mental health and substance abuse (MHSA) rose at double-digit rates from 1997 through 2003. In this presentation, we describe clinical, economic, and policy developments that may alter the MHSA drug spending growth trajectory. Specifically, we review four factors – safety, efficacy, the spread of generic medications, and more restrictive prescription drug benefit design – that may dramatically lower future MHSA drug spending growth. We also describe trends that may continue to propel growth: “off-label” and “augmentation” MHSA drug prescribing, the MHSA new drug pipeline, prescription drug marketing, and the Medicare prescription drug benefit. We conclude from this review that the double-digit growth of MHSA prescription drug expenditure experienced over the 1993-2003 period may not portend future high spending. We also point out the importance of recognizing that tremendous differences that exist in the drugs used to treat mental and substance use disorders - and the factors influencing their use and spending. There is considerably more knowledge surrounding the neuroscience and development of drugs used to treat mental illness than for drugs used to treat substance use disorders. Given this fact, recent advances in the neuroscience of substance use disorders, as well as recent interest in increasing drug development efforts for addictions, may result in future use and spending growth that equals the growth seen for psychotherapeutic agents used for mental illness. As administrators and others design new policies to respond to historically high MHSA spending growth, it is important to be mindful of the factors that are influencing spending.