Introduction:
Tonsillectomy is one of the most common surgeries in the world and the most common problem is post-tonsillectomy pain and bleeding. The relief of postoperative pain helps increase early food intake and prevent secondary dehydration. One method for relieving pain is peritonsillar injection of epinephrine along with an anesthetic, which has been shown to produce variable results in previous studies. Study Deign: Prospective case-control study. Setting: A tertiary referral centers with accredited otorhinolaryngology-head & neck surgery and anesthesiology department.
 
Materials and Methods:
Patients under 15 years old, who were tonsillectomy candidates, were assigned into one of three groups: placebo injection, drug injection before tonsillectomy, and drug injection after tonsillectomy. The amount of bleeding, intensity of pain, and time of first post-operative food intake were evaluated during the first 18 hours post operation. 
 
Results:
The intensity of pain in the first 30 minutes after the operation was lower in the patients who received injections, but the difference was not significant during the first 18 hours. The intensity of pain on swallowing during the first 6 hours was also lower in the intervention groups as compared with the placebo group. The amount of bleeding during the first 30 minutes post operation was lower in the two groups who received injections, but after 30 minutes there was no difference.
 
Conclusion: 
Injection of epinephrine and bupivacaine pre- or post- tonsillectomy is effective in reducing pain and bleeding. The treatment also decreases swallowing pain in the hours immediately after surgery.