LETTERS TO THE EDITOR How Can We Ameliorate Irinotecan-Associated Diarrhea in Children With Poor Compliance for Oral Cephalosporin?

study, without cephalosporin prophylaxis, severe diarrhea, grade 3‐4 was observed as high as 34%. Therefore, we decided to carry out cephalosporin prophylaxis beforehand. We gave him cefpodoxime prophylaxis from 5 days prior to, and until 3 days after, the treatment. He experienced less than grade 2 diarrhea after irinotecan therapy, suggesting the preventive effects of cefpodoxime. High dose irinotecan was thus repeated uneventfully for three courses. During the fourth course, however, he refused to take oral cefpodoxime because of nausea on the third day of the treatment. Maximum dose of granisetron/ondansetron did not clear his symptoms. We gave him intravenous ceftriaxone at 100 mg/kg/ day for 3 days after the treatment. He experienced only mild grade 1 diarrhea, showing that adding intravenous ceftriaxone successfully reduced IAD. Ceftriaxone has been shown to be effective in killing the aerobic intestinal bacteria [3], whereas the effects on anaerobic bacteria are minimal compared with cefoperazone, which is a mainly bileexcreting type of antibiotics. As almost half of ceftriaxone is excreted to the intestine, it can eradicate the intestinal bacteria that produces glucuronidase which converts SN-38G to toxic SN-38 [2]. It is not uncommon for children to refuse to take medication orally. Therefore, it is reasonable to consider a strategy for a nonoral route of cephalosporin prophylaxis. Although further studies with bile excreting-types of antibiotics are needed, intravenous ceftriaxone may be an option to reduce IAD for patients who cannot tolerate oral antibiotics.