<prompt> Most commonly used local anaesthetics -DibueaineBupivacainePrilocaineTetracaine  <response>: Ans. is b i.e., BupivacaineBupivacaineo Bupivacaine is 2nd most commonly used local anaesthetic after lidocaine.o Bupivacaine has the highest local tissue irritancy amongst local anaesthetics,o It is the most cardiotoxic local anaesthetic.o Levobupivacaine The S- enantiomer of bupivacaine is less cardiotoxic and less prone to cause seizure,o Concentrations used for bupivacaine are : - Nerve block : 0?5, Epidural : 0?25 - 0?5 , and spinal : 0?5.o Maximum safe dose is 2 mgkg without adrenaline and 3mgkg with epinephrine. 