Mild cases of bacillary dysentery are often self-limiting and
do not require antibiotics but severe cases require ciprofloxacin
or macrolide antibiotics.
Other causes of blood in stools are hemorrhoids and anal fissures, aspirin or nonsteroidal anti-inflammatory medications, inflammatory bowel disease, diverticulosis, polyps (small growths) and cancerous tumors (malignant growths of tissue).
But as you are having diarrhea along with the blood in stools,so chances of dysentery are quite high.