THERAPEUTICS

Brands

• Xylocaine, Akten, Alphacaine, Anestacon, Dentipatch, Glydo, Lidocaton, Zingo

Generic?

• Yes

Class

• Antiarrhythmic

Commonly Prescribed for

(FDA approved in bold)

• Regional anesthesia

• Ventricular arrhythmias

• Post-herpetic neuralgia (patch only)

• Intractable headache

• Trigeminal autonomic cephalalgia

• Symptomatic myotonia

• Pain after spinal cord injury

• Tinnitus

How the Drug Works

• Class 1b antiarrhythmic agent. It blocks fast voltage-gated sodium channels on neuronal cell membrane, resulting in inhibition of the ionic flow required for initiation and conduction of action potentials and thus creating the anesthetic effect

• It also reduces the effective refractory period in Purkinje fibers in the heart and raises the depolarization threshold of the ventricle during diastole

How Long Until It Works

• Anesthetic and antiarrhythmic effects will occur within minutes

• May take more time (days or weeks) to see relief and determine the most effective dose in myotonia or pain disorders

If It Works

• Continue to use with appropriate monitoring

If It Doesn't Work

• Check serum levels and if not effective change to an alternative agent

Best Augmenting Combos for Partial Response or Treatment-Resistance

• Bupivacaine for long-acting local anesthesia

Tests

• Obtain ECG at baseline and for any new symptoms. Check a serum lidocaine level to guide therapy (1.5–6mcg/mL) and for any AEs

ADVERSE EFFECTS (AEs)

How the Drug Causes AEs

• Drug effect blocking sodium channels

Notable AEs

• Dizziness, bradycardia, paresthesias, perioral numbness, hypo or hypertension, and tremor. Convulsions, visual disturbances (including hallucinations), depression, euphoria, agitation, or paranoid ideation

Life-Threatening or Dangerous AEs

• New or worsening cardiac arrhythmias

• Methemoglobinemia

Weight Gain

• Unusual

Sedation

• Unusual

What to Do About AEs

• Check serum level and ECG. For serious AEs, discontinue drug

Best Augmenting Agents to Reduce AEs

• Most AEs cannot be reduced by an augmenting agent