To our knowledge, the effect of combining magnesium with bupivacaine for post tonsillectomy analgesia has not been studied previously. Despite an abundant literature on post-tonsillectomy analgesia, no analgesic protocol has been standardized.Local infiltration of local anesthetics and adjuvant analgesics is playing an increasingly important role in the arsenal of post-tonsillectomy analgesia. Parietal infiltration of local anesthetics is an effective technique, providing analgesic benefits for the patient in many indications. The benefit is direct, in the form of improved postoperative pain, and indirect, in the form of reduced morbidity associated with postoperative morphine consumption.In this study, we set out to assess the effect of combining magnesium with bupivacaine on the quality of analgesia and postoperative complications.