In this double-blind study carried out at five sites in Germany, 40 patients suffering from Crohn's disease receiving a stable daily dose of steroids at an equivalent of 40 mg or less of prednisone for at least 3 weeks were administered a herbal blend containing wormwood herb (3 x 500 mg/day) or a placebo for 10 weeks. Besides steroids, 5-aminosalicylates, if dose remained constant for at least 4 weeks prior to entering the trial and/or azathioprine, stable dose for at least 8 weeks, or methotrexate, stable dose for at least 6 weeks, were permitted as concomitant medications. The recruited 40 patients - 20 in each treatment group, were evaluated with the help of a Crohn's Disease Activity Index (CDAI) questionnaire, an Inflammatory Bowel Disease Questionnaire (IBDQ), the 21-item Hamilton Depression Scale (HAMD) and an 8-item Visual Analogue Scale (VA-Scale) in 2-week intervals during the first 10 study weeks, and then at week 12, 16 and 20, which were the trial-medication free observation periods. The initial stable dose of steroids was maintained until week 2, after that a defined tapering schedule was started so that at the start of week 10 all the patients were free of steroids. At the end of week 10 the trial medication was also discontinued. The concomitant medications were maintained at the same dose levels till the end of the observation period that was the end of week 20. There was a steady improvement in CD symptoms in 18 patients (90%) who received wormwood in spite of tapering of steroids as shown by CDA-Index, IBDQ, HAMD, and VAS. After 8 weeks of treatment with wormwood there was almost complete remission of symptoms in 13 (65%) patients in this group as compared to none in the placebo group. This remission persisted till the end of the observation period that was week 20, and the addition of steroids was not necessary. In two (10%) patients did the re-starting of corticoids become necessary? On the other hand, the CD conditions of the patients who received the placebo deteriorated after the tapering of steroids, and re-starting steroids became necessary in 16 (80%) patients in this group after week 10. These results strongly suggest that wormwood has a steroid sparing effect. The improvements in HAMD scores indicate that wormwood also has an effect on the mood and quality of life of CD patients, which is not achieved by other standard medications.