The purpose of this study was to compare the effects and abrupt discontinuation of buspirone 15 or 20 mg tid and lorazepam 3 or 4 mg tid following 8 weeks of treatment. A total of 43 outpatients with generalized anxiety disorder were included in the study and 39 entered the withdrawal phase. 2. Clinical assessments were performed at baseline, 2, 4, 6 and 8 weeks (active phase) and after 9 and 10 weeks (withdrawal phase). These included the Hamilton anxiety scale, the visual analogue scale, the CHESS 84 (a check list for the evaluation of somatic symptoms) and the Lader tranquilizer withdrawal scale (translated in french). 3. Results show similar efficacy for lorazepam and buspirone during the active phase with a higher significant difference for buspirone on the CHESS 84 in relation with neurovegetatives symptoms: lorazepam D0 :16.30 +/- 3.14 D56: 5.10 +/- 0.93 (p < or = 0.01) buspirone D0 :18.82 +/- 3.4 D56: 4.73 +/- 1.18 (p < or = 0.001) No withdrawal phenomena was observed for both drugs using HAM-A lorazepam D63 :12.59 +/- 2.26 D70: 12.0 +/- 1.75 (p = ns) buspirone D63 :10.05 +/- 1.28 D70: 10.32 +/- 1.82 (p = ns) and the same significant difference using Lader scale: lorazepam D63 :4.44 +/- 0.89 D70: 6.96 +/- 1.28 (p < or = 0.05) buspirone D63 :2.95 +/- 0.66 D70: 4.15 +/- 0.92 (p < or = 0.05). 4. This study confirmed that buspirone was as effective as lorazepam at D56 in monitored outpatients with generalized anxiety disorder.(ABSTRACT TRUNCATED AT 250 WORDS)