The kampo medicine Hangeshashin-to (TJ-14), which contains baicalin, a β-glucuronidase inhibitor, alleviates diarrhoea induced by irinotecan (CPT-11). Japanese researchers conducted a randomised comparative trial to investigate whether support with TJ-14 would prevent and control CPT-11-induced diarrhoea. Of 44 previously untreated patients with advanced non-small-cell lung cancer, 41 (18 in the TJ-14 group; 23 in the control group) were available for evaluation. The chemotherapy regimen consisted of a combination of cisplatin and CPT-11. TJ-14 (7.5 g/day) was administered orally. Of the 41 patients, 39 experienced diarrhoea. Compared with the control group, the TJ-14 group showed a significant improvement in diarrhoea grades as well as a reduced frequency of diarrhoea grades 3 and 4. However, the two groups showed no differences in the frequency of diarrhoea or the number of days the symptoms continued.