It is important to be concerned upon seeing red blood in stool. Swollen blood vessels in the anus or lower rectum, called hemorrhoids, might be the main cause. Alternatively, anal fissures, inflammatory bowel disease, or an infection could also be responsible. Make sure you drink plenty of fluids, eat food high in fiber, and do not strain when passing stool. To get proper treatment, you must see a gastroenterologist who will carry out the necessary medical checks before giving medication.