The cause of red stool and red urine is considered to be the effect of food, such as eating red dragon fruit. Because the anthocyanins in red dragon fruit cannot be absorbed by the body, the excreted stool and urine will appear red. In addition, if you take rifampin, its metabolites will also be red, not only the urine and feces are red, but also the tears, sweat and saliva. Red feces and urine caused by the above-mentioned food and medications do not have a special odor and may disappear on their own within 1-2 days after stopping the above-mentioned food and medications. Otherwise, it is necessary to consider whether it is gastrointestinal bleeding or the presence of hematological disorders, and if necessary, it is necessary to go to the hospital for consultation.