Antiarrhythmic agents include-

Group I -  Moricizine, Qunidine, Procainamide, Disopyramide, Lidocaine, Phenytoin,

                Tocainide, Mexiletine, Flecanide, , Propafenone
Group II- Propranolol, Esmolol, Acebutol
Group III- Bretylium, Amiodarone, Solatol
Group IV- Verapramil, Digoxin, Adenosine

Interacting drugs- summary

+  Lidocaine-

Beta blockers
 increased lidocaine levels ,possibly resulting in in toxicity

Cimetidine 
  decreased lidocaine clearance with possible toxicity. Ranitidine and
      other H2 antagonists, do not appear to interact.

Procainamide
 additive cardiodepressant action occur with potential for              
  conduction abnormalities

Tocainide
 concomittant use cause an increased incidence of adverse
   reactions

Lidocaine +
Succinyl choline
 prolongation of neuromuscular blockade occur.
              

Acute management of ventricular arrhythmias occuring during cardiac manupulation, viz. cardiac surgery, acute myocardial infraction

Antiarrhythmic agents include-

Group I -  Moricizine, Qunidine, Procainamide, Disopyramide, Lidocaine, Phenytoin,

               Tocainide,  Mexiletine, Flecanide, Propafenone
Group II- Propranolol, Esmolol, Acebutol
Group III- Bretylium, Amiodarone, Solatol
Group IV- Verapramil, Digoxin, Adenosine

Lightheadedness, nervousness, drowsiness, dizziness, apprenhension, confusion, mood changes, doom anxiety, hallucinations, euphoria, blurred or double vision. Hypotension, bradycardia, cardiovascular collapse, which may lead to cardiac arrest.

Hypersensitivity to amide local aneathetics, Stokes-Adams syndrome, Wolff-Parkinson White syndrome, severe degrees of sinoatrial, atrioventricular(AV) or intraventricular block in the absence of an artificial pacemaker.

Special precautions:

Malignant hyperthermia- safety of amide local anesthetics in patients with genetic predisposition of malignant hyperthermia has not been established. Use lidocaine with caution in such patients

Indications:

Acute management of ventricular arrhythmias occuring during cardiac manupulation, viz. cardiac surgery, acute myocardial infraction

Dosage:

IM- 300mg- the deltoid muscle is preferred- avoid intramuscular injection.

Pharmacology:

Lidocaine increases the electrical stimulation threshold of the ventricle during diastole. In therapeutic doses, lidocaine produces no change in myocardial contractility, systolic arterial blood pressure or absolute refractory period.

Pregnancy:

Use during pregnancy when needed.

Lactation:

Excercise caution when administering to a nursing woman.