1. Class I
   1. Na+ Channel Blockers
      1. quinidine
         1. MOA:
            1. Prolonged depolarization and delay repolarization (lengthen duration of action potential)
            2. EKG shows
            3. Widened QRS
            4. Prolonged QT interval
         2. Indications:
            1. Drug of choice for malaria
            2. Supraventricular dysrhythmias
            3. Ventricular dysrhythmia
         3. Adverse Effects:
            1. Watch for vasodilation & hypotension (lightheadedness)
            2. Diarrhea frequent
            3. Blurry vision
            4. Bitter taste
            5. Tinnitus
         4. Nursing Considerations:
            1. If taken with digoxin, it doubles digoxin levels
            2. Take with food to alleviate GI symptoms
      2. lidocaine
         1. MOA:
            1. Local anesthetic
            2. Decreased automaticity in ventricles and His-Purkinje & accelerated repolarization (shortens the duration of action potential)
            3. EKG shows
            4. Little to no effect
         2. Indications:
            1. Local anesthesia
            2. Short term therapy for ventricular dysrhythmias only
         3. Adverse Effects:
            1. CNS effects
            2. Confusion
            3. Drowsiness
            4. paresthesias
            5. Toxicity
            6. Seizures and/or respiratory arrest
         4. Nursing Considerations:
            1. Given IV
            2. May also be given intradermal, topical (2% or 4%)
      3. flecainide
         1. MOA:
            1. Reduce conduction velocity in atria, ventricles, and His-Purkinje system
            2. Delay ventricular repolarization & increase refractory period
            3. EKG shows
            4. Prolong PR Interval
            5. Widening of QRS
         2. Indications:
            1. Severe ventricular dysrhythmias not responsive to other
         3. Adverse Effects
            1. May exacerbate existing dysrhythmias or create new ones
            2. Negative inotrope
            3. Increased mortality in asymptomatic ventricular tachycardia
2. Class II
   1. Beta Blockers (BB)
      1. propanalol
         1. Class:
            1. Beta Blocker
         2. MOA:
            1. BBs block B1 & B2 adrenergic receptors (heart) which slows HR/slows time for conduction and decreases force of contraction
            2. EKG shows
            3. Prolong PR interval
         3. Indications:
            1. Afib
            2. Tachycardias
         4. Adverse Effects:
            1. Heart Failure/AV Block
            2. Hypotension
            3. Bronchospasm
3. Class III
   1. K+ Channel Blockers
      1. amiodarone
         1. Class:
            1. K+ Channel Blockers
         2. MOA:
            1. These drugs delay repolarization---> prolong action potential duration and effective refractory period
            2. EKG shows
            3. Widening QRS/Prolonged PR and QT Intervals
         3. Indications:
            1. Serious dysrhythmias due to toxicities
            2. Vtach & Vfib
            3. off-label
            4. atrial fibrillation- convert a-fib to sinus rhythm and maintain NSR
         4. Adverse Effects:
            1. Severe organ toxicities
            2. *Lung damage
            3. Also cardiac, liver, dermatologic, and thyroid
            4. CI pregnancy/lactation
            5. Visual impairments
            6. Sun exposure turns skin blue-gray
         5. Nursing Considerations:
            1. Monitor drug interactions
            2. Increases digoxin/warfarin/statin levels
            3. Grapefruit juice increases levels
4. Class IV
   1. Ca+ Channel Blockers (CCB)
      1. verapamil
         1. Class:
            1. Ca+ Channel Blockers
         2. MOA:
            1. Decreased Contractions/HR/Conduction velocity (not for Heart Failure patients)
            2. Vasodilates blood vessels
            3. Similar to BBs (affect the heart's Beta 1 adrenergic receptors)
         3. Indications:
            1. Effective in controlling Afib and ventricular dysrhythmias
            2. Chronic HTN as second-line therapy
         4. Adverse Effects:
            1. For verapamil
            2. Constipation
            3. Dizziness
            4. Pedal edema
            5. Bradycardia
         5. Nursing Considerations:
            1. For verapamil- Food & Drug Allergies
            2. Digoxin
            3. Increases plasma levels of digoxin--> dig toxicity
            4. Grapefruit Juice
            5. Inhibits intestinal and hepatic metabolism of many drugs--> rise in drug levels
            6. Beta blockers
            7. Cardio suppression, so administer several hours apart
            8. verapamil Toxicity
            9. Severe hypotension/bradcardia/AV block
            10. Treatment
            11. Gastric lavage
            12. Activated charcoal
            13. Increase fluids
            14. Trendelenburg position
            15. IV Calcium Gluconate
            16. Nursing Implications for verapamil
            17. VS
            18. Increase fluids
            19. Weight Daily
            20. I&O
      2. diltiazem
5. Class V
   1. Others
      1. digoxin
      2. adenosine
         1. MOA:
            1. Decreases electrical activity in SA node and slows conduction through AV node to decrease heart rate
            2. EKG shows
            3. Prolong PR interval
         2. Indications:
            1. Given for SVT to convert to sinus rhythm
         3. Adverse Effects:
            1. Passes quickly!
            2. Sinus bradycardia
            3. Dyspnea due to bronchoconstriction
            4. Hypotension
            5. Flushing
         4. Nursing Considerations:
            1. Requires fast IV push
            2. Extremely short half-life
            3. Give IV bolus via PICC or central line
            4. Must be on EKG monitor
6. Medical Acronyms