• antidepressants;
  • dysthymia;
  • tachyphylaxis;
  • tolerance

Aim:  The main goals of this chart-review study were to examine the rate of tachyphylaxis during treatment of dysthymia with antidepressants, to compare the incidence of tolerance during trials of selective serotonin reuptake inhibitors (SSRI) and non-SSRI and to give descriptive analysis of the cases of tachyphylaxis.

Methods:  The retrospective naturalistic chart review study included 52 cases of successfully treated (with different antidepressants) patients suffering from dysthymia. The overall number of the cases of tolerance to antidepressants were registered as well as the rate of these phenomena in the groups treated with SSRI and non-SSRI.

Results:  The cases of tolerance/tachyphylaxis were observed in 12 patients (23% of patients) and in 13 trials (22.4% of trials). All cases of tolerance occurred during monotherapy. No cases of tachyphylaxis were observed in the non-SSRI group while in the SSRI group, tolerance at some stage of the treatment was detected in 41.9% of the successful cases (P < 0.001).

Conclusion:  During the treatment of dysthymia with antidepressants in the SSRI group, tachyphylaxis/tolerance might be observed in a relatively in high proportion of cases.