Psychotropic Drug Prescribing in the United States

Controversy surrounding the extent of prescribing and use of psychotropic drugs-including the benefit-risk balance and the dollar expenditures-has been ongoing both nationally and internationally for many decades.1-18 This article presents currently available data on psychotropic drug prescribing in the United States. On a yearly basis, the journal Drug Topics-a publication for pharmacy professionals-provides data on the top 200 drugs based on total prescriptions for generic and branded (brand-name) drugs, as well as the top 200 generic and branded drugs based on retail dollars. According to Drug Topics, the source of the information is "SDI/Verispan, VONA." SDI/Verispan is a private health care analytics corporation, and VONA is an acronym for Vector One National Audit. The data do have significant limitations. Because only retail prescriptions are included, institutional drug use is not likely to be captured. Use of drugs not appearing in the top 200 will also not be captured. Therefore, the overall numbers will underestimate the actual extent of drug use. Furthermore, the source does not distinguish between new and refill prescriptions, and the number of dose units per prescription is not available. Finally, information is not available on the age distribution of the patients filling the prescriptions. Despite the limitations, the data source provides a telling snapshot of psychotropic drug use and expenditures in the United States. We divided the various psychotropic drugs into their traditional categories based on pharmacologic properties and labeled indications: anxiolytic, hypnotic, antidepressant, and antipsychotic. The data source did not allow determination of "off-label" use, and we did not consider drugs primarily labeled as anticonvulsants for off-label prescribing as antidepressants or mood stabilizers. The most recently available data (for calendar year 2009) indicate total retail prescriptions for psychotropic drugs exceeding 380 million, at a net dollar cost just over $22 billion (Table 1). Generics accounted for 77% of the prescription numbers but only 20% of the total dollar expenditures; conversely, brand-name drugs accounted for 23% of prescriptions and 80% of expenditures (Table 1, Fig. 1). The average cost per prescription (dividing total expenditures by total prescriptions) was $15.23 for generics, compared with $198.47 for brand-name drugs. A similar price differential was evident for individual drugs within each category (Table 2), and for the hypnotic and antidepressant categories collectively (Table 1). For anxiolytics, only generics appeared in the top 200 (Table 2). For antipsychotics, complete data were available only for olanzapine (Zyprexa), probably because most antipsychotic drug use is institutional.FIGURE 1: Total retail prescriptions (left) and total expenditures (right) for psychotropic drugs in 2009, divided according to brand-name and generic drugs.TABLE 1: Retail Prescriptions and Expenditures for Psychotropic Drug Categories in 2009TABLE 2: Retail Prescriptions and Expenditures for Individual Psychotropic Drugs in 2009An independent source of retail drug cost data was obtained online from www.drugstore.com, a national chain. The cost per dose unit for specific drugs was determined for a dosage size in the middle range of those available, based on a prescription for 90 or 100 dose units. When these values were compared with the average cost per prescription from the Drug Topics list (Table 2), a high degree of concordance was evident (Fig. 2). Dividing the cost per prescription by the cost per dose unit yields an estimate of dose units per prescription. The average values were 48 for anxiolytics, 32 for hypnotics, and 37 for antidepressants. It is of interest that most of the drugs prescribed in generic form also remain available as brand-name drugs. For 13 of the generic drugs in Table 2, and for 7 others not listed in the table, we calculated the ratio of the cost per dose unit for the brand name divided by the corresponding cost per dose unit for the generic. The average ratio was 9.8, with a range of 1.2 to 45.8.FIGURE 2: Relation between retail cost for a typical dose unit as quoted by www.drugstore.com (x axis) and the average cost per prescription from Drug Topics (y axis), for a series of 26 generic or brand-name psychotropic drugs. The solid line was determined by linear regression.A number of important points emerge from this analysis. Prescribing of the older benzodiazepine derivations-now available as generics-continues to be extensive. Combined prescriptions for alprazolam, clonazepam, lorazepam, and diazepam exceeded 100 million in 2009. Generic temazepam accounted for another 9 million, and immediate-release zolpidem for 30 million. Alprazolam was the single most widely prescribed psychotropic drug. Antidepressants account for the largest component of psychotropic drug prescriptions, and most of these are the selective serotonin reuptake inhibitors and the new mixed-mechanism agents. The numbers do not provide information on how the prescriptions apply to depressive disorders as such, as opposed to obsessive-compulsive disorders, panic attacks, anxiety, chronic pain, fibromyalgia, and so on. Generic drugs account for 77% of all prescriptions, but the remaining 23% of prescriptions-for brand-name drugs-consume 80% of net expenditures. The cost difference is huge. Yet advertising and promotion of brand-name drugs-to health care professionals and to the lay public-are extensive. Prescribing physicians, formulary committees, and reimbursement plans face the difficult task of sorting through promotional materials and scientific data to confront the questions of whether any increment of benefit of brand-name drugs in terms of efficacy and tolerability justifies the large increment in cost relative to similar drugs with similar properties available as inexpensive generics.19-34