Trigeminal neuralgia (TN) is a syndrome affecting usually one half of the face and consisting of severe pains within one or more branches of the nerve. One of the methods for conservative treatment is using anesthetic drugs in the form of perineural sensory branch blockades n. V. If these are found ineffective, alcoholic blockades are used in some cases although complications like necrosis, tissue fibrosis or risk of developing a neuroma may occur. The paper describes a case of complication after alcoholic blockade into left mental nerve, namely oral tissue necrosis.