[Clinical evaluation of antiemetic effects of 5-hydroxytryptamine receptor type 3 (5HT3 receptor) antagonists based on changes in eating condition in cancer patients receiving chemotherapy].

To evaluate the antiemetic effects of 5-HT(3) receptor antagonists, we investigated the relationship between condition of food intake and occurrence of nausea and vomiting. We collected data such as sex, age, disease, combination of steroids and central antiemetic agents, eating condition, and vomiting condition from medical records in 33 hematologic cancer patients receiving chemotherapy; combination with 5-HT(3) receptor antagonists. The conditions of food intake and nausea/vomiting were checked at 4 mealtime points (lunch, supper, breakfast, and next lunch) after chemotherapy, and were recorded as 1, 3, or 5 as each condition score. To calculate eating scores and nausea/vomiting scores, the sum of scores from 4 mealtime points was used. We found a significant negative correlation between eating scores and nausea/ vomiting scores (n=62, p<0.01). At eating points in which combination therapy with steroids and central antiemetic agents was not given, antiemetic effects of granisetron, azasetron and ramosetron were compared and revealed that azasetron was the most effective antiemetic agent. This result is in agreement with our previous study predicting antiemetic effects of 5-HT(3) receptor antagonists based on the receptor occupancy theory. This study suggests that eithes receptor occupancy or eating score is a useful indicator for assessment of the efficacy of 5-HT(3) receptor antagonists.