Lidocaine

Class

• • amino amide-type local anesthetic

  • class 1B antiarrhythmic drug

Indications

• • infiltration, block and surface anesthesia

  • postherpetic neuralgia

  • tinnitus

• ventricular arrhythmias

Administration/Absorption

• • Injected local anesthetic (sometimes combined with epinephrine to reduce bleeding)

  • IV

  • Topical gel/patch

Dosage

Distribution

Mechanism

• • alters signal conduction in neurons by blocking the fast voltage gated sodium (Na⁺) channels in the neuronal cell membrane

Excretion

• • 95% metabolized (dealkylated) in the liver by CYP3A4 to the pharmacologically-active metabolites monoethylglycinexylidide (MEGX) and then subsequently to the inactive glycine xylidide

  • elimination half-life of lidocaine is approximately 90–120 minutes in most patients

Side effects

Interactions

Contraindications

• • Heart block, second or third degree (without pacemaker)

  • Severe sinoatrial block (without pacemaker)

  • Serious adverse drug reaction to lidocaine or amide local anaesthetics

  • Concurrent treatment with quinidine, flecainide, disopyramide, procainamide (Class I antiarrhythmic agents)

  • Prior use of Amiodarone hydrochloride

  • Hypotension not due to Arrhythmia

• Bradycardia

• Accelerated idioventricular rhythm

• Pacemaker