lidocainerx.com

People mostly meet lidocaine in a dentist's chair. A focused site can explain what numbing feels like, how long it lasts and what to avoid afterwards.

Generic and neutral, the name suits clinics and pharmacies.

What it is. Lidocaine is an amide local anesthetic and class IB antiarrhythmic.^[C1][C4]

FDA-approved uses. Injection for local or regional anesthesia; 5% patch for postherpetic neuralgia pain; viscous solution for painful irritated mouth and throat; topical creams and jellies for surface anesthesia; IV for certain ventricular arrhythmias.^{[C1][C2][C3][C4]}

How it works. It blocks voltage-gated sodium channels in nerve membranes, stopping the initiation and conduction of nerve impulses.^[C4]

Forms and strengths. Injection 0.5% to 2% (with or without epinephrine), 5% patch, 2% viscous solution, 2% jelly, 4% and 5% creams and ointments.^{[C1][C2][C3][C4]}

Key warnings and side effects. Contraindicated with amide anesthetic allergy. Too much absorbed lidocaine causes systemic toxicity: numbness of the mouth, ringing ears, confusion, seizures and cardiac arrhythmias. Viscous lidocaine 2% carries a boxed warning: life-threatening and fatal events (seizures, cardiopulmonary arrest) in infants and young children; it is not approved for teething pain. Methemoglobinemia is a rare risk.^{[C1][C2][C3][C4]}