Lidocaine Hydrochloride/Epinephrine

**Semantic type:** Pharmacologic Substance

**Definition:** A combination agent composed of the hydrochloride salt form of lidocaine, an aminoethylamide and a prototypical member of the amide class of anesthetics, and the synthetic form of the naturally occurring sympathomimetic amine epinephrine, with local vasoconstricting and anesthetic activities. Upon local administration of lidocaine hydrochloride/epinephrine by injection, epinephrine binds to and stimulates vascular alpha-adrenergic receptors, thereby causing vasoconstriction. Lidocaine interacts with voltage-gated sodium (Na+) channels in the nerve cell membranes and blocks the transient increase in permeability of excitable membranes to Na+. This prevents the generation and conduction of nerve impulses and produces a reversible loss of sensation. By administering epinephrine, lidocaine's potential to disperse into the surrounding tissue is reduced, thereby increasing its local efficacy, and enhancing and prolonging the anesthetic effect.

**Synonyms:** - Lidocaine HCI and Epinephrine - Lidocaine/Epinephrine - Xylocaine-Epinephrine - Xylocaine/Epinephrine