Differences in clinical effect and tolerance between fluvoxamine and paroxetine: a switching study in patients with...

We examined whether discontinuation and the responses to fluvoxamine (FLV) administration could predict the subsequent discontinuation and the responses to paroxetine (PRX) in patients with depression.

The subjects comprised 106 outpatients who were diagnosed with depression, and clinical evaluation was conducted every 2 weeks. Patients who discontinued FLV because of side effects or did not achieve remission with 200 mg/day of FLV, the drug was switched to PRX. The maximum dose of PRX was 40 mg/day.

Among 10 patients who discontinued FLV, PRX was also discontinued in one patient. Of 33 patients without remission on FLV, PRX was discontinued because of side effects in two patients. There was no statistical difference in the discontinuation rates between the two groups. Four of 10 patients who discontinued FLV achieved remission, while nine of 33 patients without remission with FLV achieved remission with PRX. The remission rate was not significantly different between the two groups.

Discontinuation and the responses related to FLV could not serve as a predictor for the subsequent discontinuation and the responses related to PRX.