TY - CHAP M1 - Book, Section TI - Local Anesthetics A1 - Schwartz, David R. A1 - Kaufman, Brian A2 - Hoffman, Robert S. A2 - Howland, Mary Ann A2 - Lewin, Neal A. A2 - Nelson, Lewis S. A2 - Goldfrank, Lewis R. PY - 2015 T2 - Goldfrank's Toxicologic Emergencies, 10e AB - Local anesthetics are xenobiotics that block excitation of and transmission along a nerve axon in a predictable and reversible manner. The anesthesia produced is selective to the chosen body part in contrast to the nonselective effects of a general anesthetic. Local anesthetics do not require the circulation as an intermediate carrier, and they usually are not transported to distant organs. Therefore, the actions of local anesthetics are largely confined to the structures with which they come into direct contact. Local anesthetics may provide analgesia in various parts of the body by topical application, injection in the vicinity of peripheral nerve endings and major nerve trunks, or via instillation within the epidural or subarachnoid spaces. The various local anesthetics differ with regard to their potency, duration of action, and degree of effects on sensory and motor fibers. Toxicity may be local or systemic. With systemic toxicity, the central nervous system (CNS) and cardiovascular systems typically are affected. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/04/19 UR - accessemergencymedicine.mhmedical.com/content.aspx?aid=1108431529 ER -