The treatment of depression with paroxetine in psychiatric practice in Germany: the possibilities and current limitations of drug monitoring.

A drug monitoring of the antidepressant paroxetine was carried out in Germany from August 1992 to November 1993. The principal aim of this study was to collect demographic, diagnostic, efficacy, and medical-safety data regarding patients who were treated for up to 12 weeks with this SSRI. A secondary goal was the investigation of differences between patients who left treatment after 6 weeks or earlier and those who continued treatment. Evaluable data were obtained from 507 psychiatrists for 2817 patients, 1301 of whom extended treatment beyond 6 weeks. 64% of the patients had been pretreated for the current episode of depression. 50% were considered by their doctors to have either chronic or recurrent illness and 92% to possess moderate to severe symptomatology. Concomitant psychotropic medication was reported in 43% of cases, the most frequent medications being benzodiazepines, neuroleptics, and/or tricyclic antidepressants. Clear or complete improvement was noted for 63% of assessable patients by the end of week 6 and for 79% of the patients who extended treatment to 12 weeks. There were significantly more patients with DSM major depression and severe symptoms in the treatment-extender than in the 6-week treatment group. Paroxetine was tolerated well by most patients: of the 1009 adverse events reported, only 17 were considered "serious". There were no suicides or cases of overdose attributable to paroxetine. The discussion of these results is the basis for a critical appraisal of postmarketing-surveillance methodology. It is concluded that, despite its present structural weaknesses as compared to controlled investigations, drug monitoring of a new medication in the immediate postmarketing period can give insights into the treatment of large numbers of patients under private-practice conditions. However, drug monitoring as it is conducted in Germany can have different and perhaps conflicting functions which may limit its effectiveness. The authors recommend that all interested parties (physicians, the pharmaceutical industry, regulatory bodies) engage in a continuous dialog aimed at clearly formulating the goals and improving the methodology of drug monitoring.