The aim of this review is to provide an adequate knowledge on long acting anaesthetics like Bupivacaine, tetracaine, etidocaine, ropivacaine and merivacaine in oral cavity along with its complications which include both local and systemic complications.Local anesthesia is defined as a loss of sensation in a circumscribed area of the body by a depression of excitation in nerve endings or an inhibition of the conduction process in the peripheral nerves. The reason for this review is to provide sufficient knowledge on long acting anaesthetics along with its complications.