Combination of citalopram plus paliperidone is better than citalopram alone in the treatment of somatoform disorder: results of a 6-week randomized study.

The objective of this study was to evaluate the effectiveness and tolerability of citalopram versus citalopram plus paliperidone combination therapy in patients with somatoform disorders (SDs). In this 6-week, randomized, fixed-dose study, 60 patients with SD (ICD-10 F45.0), undifferentiated SD (F45.1), and somatoform autonomic dysfunction (F45.3) were randomly assigned to receive citalopram (20 mg/day) with or without paliperidone (3 mg/day). Four scales were used to evaluate effectiveness and tolerability at baseline and at the end of the second, fourth, and sixth week after treatment: Somatoform Disorders Screening Symptoms-7 (SOMS-7), Hamilton Anxiety Scale (HAMA), 17-item Hamilton Depression Scale (HAMD-17), and Treatment Emergent Symptom Scale (TESS). The rater was blinded to the kind of treatment patients received. (i) In the intention-to-treat population (N = 51), the overall response ratio (50% reduction in SMOS-7 scores) was significantly higher in the citalopram-paliperidone group compared with the citalopram group after a 6-week treatment (71.4 vs. 38.10%, χ² = 4.71, P = 0.03). (ii) The SOMS-7 and somatic subscore of the Hamilton Anxiety Scale (HAMA-SOM) total score of the citalopram plus paliperidone group decreased more significantly than that of the citalopram group, and a significant difference could be observed at the end of 4 weeks of treatment. (iii) There was no significant difference between the two groups in adverse effects, and no serious adverse event was reported in both groups. Our findings indicate that a combination with paliperidone is significantly better than monotherapy with citalopram whether synergistic or add-on for patients with SDs. Our results call for future studies with larger sample sizes and a longer duration to draw more definitive conclusions.