Selective serotonin reuptake inhibitor dose titration in the naturalistic setting

Little information exists regarding the use of selective serotonin reuptake inhibitors (SSRIs) in the naturalistic setting. The Regenstrief Medical Record System was used to analyze the dosing of SSRIs in the outpatient population of an urban teaching hospital. A cohort of 3350 patients was extracted, of whom 2859 had received fluoxetine and 460 sertraline. This cohort received 21,079 prescriptions. (The 31 patients who were prescribed paroxetine were eliminated from further analysis.) The mean daily dose for all patients receiving fluoxetine was 21 +/- 6 mg for the first prescription dispensed and 25 +/- 11 mg for the ninth. For fluoxetine-treated patients with depression included on their computerized medical problem list, the mean daily dose was 21 +/- 6 mg for the first prescription and 26 +/- 12 mg for the ninth. A mean of 5.0% of all patients continuing fluoxetine therapy had their daily dose increased with each prescription refill during the first nine prescriptions. The mean daily dose for all patients receiving sertraline was 59 +/- 28 mg for the first prescription and 117 +/- 66 mg for the ninth. For sertraline-treated patients with depression included on their computerized medical problem list, the mean daily dose was 57 +/- 25 mg for the first prescription and 110 +/- 65 mg for the ninth. A mean of 14.9% of all patients continuing sertraline therapy had their daily dose increased with each prescription refill during the first nine prescriptions. The frequency of sertraline dose increases was 2 to 3 times the rate for fluoxetine. Because increases in daily doses typically result from inadequate control of symptoms of depression, these findings may reflect fluoxetine's greater effectiveness in controlling symptoms during the initial stages of therapy in the naturalistic setting.