Maeda, Y., Ohune, T., Nakamura, M., Yamasaki, M., Kiribayashi, Y., & Murakami, T. (2004). Prevention of irinotecan-induced diarrhoea by oral carbonaceous adsorbent (Kremezin) in cancer patients. Oncology Reports, 12(3), 581–585.

To examine the effectiveness of two interventions to ameliorate diarrhea after treatment with irinotecan

• 2 g AST-120 (Kremezin™) oral adsorbent made of activated carbon given at the start of irinotecan infusion, immediately after irinotecan, and 3 hours later
• An oral alkalization made of 2 g NaHCO₃ (sodium bicarbonate), 2 g magnesium oxide, and 300 mg ursodeoxycholic acid given orally before irinotecan infusion and then every day for three days after

This was a nonrandomized trial of 13 Japanese patients with various cancers receiving 60–100 mg/m² irinotecan every one to two weeks, alone or in combination regimens. Patients received one of three interventions. Four patients received AST-120; one of these four had previously received irinotecan with no prophylaxis and thus served as a control. Four patients received the oral alkalization; one of these also had previously received irinotecan with no prophylaxis and thus served as a control. Including these two controls, a total of seven control patients received irinotecan with no prophylaxis.

The number of bowel movements was recorded; however, volume was not recorded.

Oral AST-120 was associated with significantly decreased numbers of daily bowel movements during irinotecan treatment compared to no prophylaxis (p < 0.05). Oral alkalization was effective in ameliorating diarrhea, but the difference was not significant.

• The sample size was very small with only 13 patients.
• One patient in the AST-120 group and one in the oral alkalization group acted as their own controls. Only three other patients were in each interventional treatment  group.
• Although further study is necessary regarding the effectiveness of oral AST-120 on plasma concentrations of irinotecan-related compounds, the absorption of irinotecan or SN-38 from the intestinal lumen is small, if any, and the remaining irinotecan-related compounds in the intestinal lumen cause diffuse mucosal damage in irinotecan treatments.