OBJECTIVE: To describe the use of oral antidiabetic drugs for management of type 
2 diabetes in the U.S. from 1990 through 2001.
RESEARCH DESIGN AND METHODS: Data on oral antidiabetic drugs were derived from 
two pharmaceutical marketing databases from IMS Health, the National 
Prescription Audit Plus and the National Disease and Therapeutic Index.
RESULTS: In 1990, 23.4 million outpatient prescriptions of oral antidiabetic 
agents were dispensed. By 2001, this number had increased 3.9-fold, to 91.8 
million prescriptions. Glipizide and glyburide, two sulfonylurea medications, 
accounted for approximately 77% of prescriptions of oral antidiabetic drugs in 
1990 and 35.5% of prescriptions in 2001. By 2001, the biguanide metformin 
(approved in 1995) had captured approximately 33% of prescriptions, and the 
thiazolidinedione insulin sensitizers (rosiglitazone and pioglitazone marketed 
beginning in 1999) accounted for approximately 17% of market share. Compared 
with patients treated in 1990, those in 2001 were proportionately younger and 
they more often used oral antidiabetic drugs and insulin in combination. 
Internists and general and family practitioners were the primary prescribers of 
this class of drugs.
CONCLUSIONS: Consistent with the reported increase in the prevalence of type 2 
diabetes, the number of dispensed outpatient prescriptions of oral antidiabetic 
drugs increased rapidly between 1990 and 2001. This period was marked by an 
increase in the treatment of younger people and the use of oral antidiabetic 
drugs in combination. With the approval in the last decade of several new types 
of oral antidiabetic medications with different mechanisms of action, options 
for management of type 2 diabetes have expanded.