Lidocaine

Summary

Lidocaine, and related drugs ending in “-caine”, like bupivacaine, mepivacaine, and tetracaine, are local analgesics used to numb pain felt in local areas. Clinically, these drugs are usually administered as local injections prior to painful procedures. In rare cases, lidocaine is administered intravenously to enter the bloodstream, where it acts as an antiarrhythmic, effective in treating ventricular arrhythmias.

Key Points

• Lidocaine
  • Mechanism
    • Sodium channel blocker
      • Blocks sodium channels and sodium influx into cardiac and nerve cells, thereby preventing depolarization and action potentials
      • Suppresses nervous activity and cardiac activity
  • Clinical Uses
    • Local analgesia
      • Has short onset and long duration
      • Only numbs the surrounding area (compared to fentanyl patches that gives systemic analgesia)
      • Viscous oral form can be used to treat oral pain due to mucositis
      • May be given in a patch, intradermal injection, or oral solution
    • Arrhythmias
      • Treats ventricular dysrhythmias such as ventricular fibrillation, ventricular tachycardia, and premature ventricular contractions (PVCs)
      • Given as an IV infusion
  • Side Effects and Adverse Reactions
    • When given via IV for arrhythmias
      • Headache
      • Bradycardia
      • Hypotension
      • Dizziness
      • Tremors