The study was done to evaluate the effect of local use of antifibrinolytic agent in the prevention of alveolar osteitis after extraction of impacted mandibular 3rd molar. The study took place on 90 consecutive patients (45 patients in each group). After surgical extraction the sockets were irrigated immediately with 10ml of solution (tranexamic acid or placebo) for 2 min. 4 times / day (every 6 hours) for 2 days. Patients returned in five to seven days for suture removal complaining of postoperative pain were examined to verify the severity of the localized osteitis which graded as mild, moderate, or severe according to the patient's stated degree of pain which scored according to visual analogue scale .The incidence of dry sockets in the group treated with 10% tranexamic acid was 6.6% compared with 28.8% in the sockets treated with placebo.  In addition, the untreated group presented with dry sockets judged to be more severe.