<s>[INST] I had a root canal today and my dentist said he felt the tooth was necrotic. During the procedure a unbearable burning sensation and pulsating pain happened when the infection began to drain. Im on a strong antibiotic now and my cheek has swelled very bad. Is the swelling normal and will the antibiotics help take it down? [/INST] Hi. Welcome to Chat Doctor . I have gone through your query and can understand your concerns. As per your complaint in case if you have started root canal treatment of tooth and there have been Chat Doctor. . Many a time when the root canal treatment is started and after first sitting the tooth is packed the pus left inside and inflammation leads to swelling, and you should consult your treating dentist and get evaluated, and he can do a cleaning of the canals of tooth as well as  </s>