amide amylocaine anatomical therapeutic chemical classification system articaine benzocaine benzoic acid bioavailability biological half-life bupivacaine butacaine cas registry number carticaine chemical formula chloroprocaine cinchocaine cocaine cyclomethycaine dentistry dimethocaine drugbank drug metabolism ester etidocaine excretion hexylcaine international union of pure and applied chemistry nomenclature iontocaine levobupivacaine lidocaine local anesthetic mepivacaine meprylcaine orthocaine pharmacology piperocaine plasma protein binding procaine proparacaine propoxycaine pubchem regulation of therapeutic goods risocaine ropivacaine route of administration sodium channel blocker tetracaine trimecaine