The main medications as well as foods that make children’s white blood cells go down are as follows: first of all, applying cephalosporins to children. The reason why children have high white blood cells is due to bacterial infections, and cephalosporins can fight bacterial infections, which will make children’s white blood cell levels drop significantly. Next, antipyretic medications. After taking fever-reducing medications such as acetaminophen or ibuprofen, children can also cause a significant drop in white blood cells. Finally, eating foods that remove heat and toxins can cause a drop in white blood cells, such as giving children green bean soup or eating watermelon, which can also decrease white blood cell levels to a certain extent.