The annual cost of lovastatin for the 148 patients with data would be $71,693 for the most recent dosages. The corresponding cost for pravastatin would be $56,875 (21% lower). Of the 168 patients changing regimen, 145 (86%) were prescribed an initial daily pravastatin sodium dose that was at least 50% lower in milligrams than that of lovastatin. During the year after the conversion the pravastatin dosage was increased for 16 (11%) of the 145 patients. It was concluded that the increase was inappropriate for seven patients. No adverse effects were examined.