Prescription Drug Spending in 2008

The Agency for Healthcare Research and Quality (AHRQ) recently issued Statistical Brief #313 identifying the top 5 therapeutic classes of outpatient prescription drugs in 2008 for adults age ≥18 in terms of expenditures. AHRQ ranked metabolic agents, central nervous system agents, cardiovascular agents, gastrointestinal agents, and psychotherapeutic agents as the top 5 drug classifications. These drugs were ranked by total expenditures out of the 18 broad therapeutic drug classes defined in 2008. AHRQ estimated these costs from the Household and Pharmacy Components of the 2008 Medical Expenditure Panel Survey (MEPS). The expenses include payments from all sources (out of pocket, private, and public insurance) for outpatient prescription drug purchases throughout the year. The expenses for the top 5 therapeutic drug classes for adults age ≥18 accounted for 67%, or $155.7 billion, of the $232.6-billion prescription drug industry. Metabolic agents accounted for the highest total expenses, at $52.2 billion. The central nervous system agents totaled $35.1 billion, the cardiovascular agents consumed $28.6 billion, the gastrointestinal agents accounted for $20.2 billion, and the psychotherapeutic agents totaled $19.6 billion, according to AHRQ’s findings. In terms of percentages of all prescribed medicine, metabolic agents accounted for 22.5%, central nervous system agents made up 15.1%, cardiovascular agents consumed 12.3%, gastrointestinal agents were 8.7%, and the psychotherapeutic agents made up 8.4% of total prescribed drug expenses. Two thirds, or 67.4%, of all adults had prescription drug expenditures in 2008, and among the adults with drug prescriptions, the central nervous system agents consumed the greatest amount, at 46%. The cardiovascular agents consumed 41.4%, while 33.8% of adults purchased metabolic agents. Gastrointestinal agents accounted for 17.7% of the adult population with prescription expenditures, and lastly, psychotherapeutic agents made up the remaining 17.1%. Gastrointestinal agents had the highest average expense per prescription, with $133. Metabolic agents averaged a total of $101, while psychotherapeutic agents cost $99. Central nervous system agents averaged $72, and the cardiovascular agents were $39 per prescription. Gastrointestinal agents accounted for >3 times the amount of total expenses compared with the lowest costing prescription of cardiovascular agents. This study was confined to outpatient prescription drugs in 2008 for adults age ≥18 in the US civilian noninstitutionalized population. Drugs excluded from these findings include over-the-counter medications and prescription medicines administered in an inpatient setting or in a clinic or physician’s office. Insulin and diabetic supplies and equipment are included in MEPS prescribed medicines estimates. The drug classifications are based on the Multum Lexicon therapeutic classification system. The cardiovascular agents included calcium channel blockers and diuretics. The central nervous system agents included analgesics, anticonvulsants, and antiparkinson agents. The gastrointestinal agents included the H2-receptor antagonists, antacids, antidiarrheals, and proton pump inhibitors. The metabolic agents included the subclasses of antihyperlipidemic agents and antidiabetic agents. Lastly, the psychotherapeutic agents included the subclass of antidepressants and antipsychotics.