(also see Calcium Channel Blockers)
| Drug and Dosage | Use | Action | Assessment: Side Effects |
|---|---|---|---|
| Amiodarone hydrochloride (Cordarone)—PO 800–1,600 mg/day loading dose; 400–600 mg/day maintenance | Life-threatening ventricular arrhythmias; supraventricular arrhythmias (e.g., atrial fibrillation) | Class III antiarrhythmic; antianginal, antiadrenergic | Muscle weakness, fatigue, dizziness, hypotension with IV; corneal microdeposits; anorexia, nausea, vomiting; photosensitivity |
| NURSING IMPLICATIONS: Monitor vital signs (VS). Expect possible CNS symptoms 1 wk after beginning drug. Instruct client to protect eyes and skin from sun | |||
| Bretylium (Bretylol)—IV 0.5–10 mg/kg q6h; IM 5–10 mg/kg (max. 250 mg in one site) | Ventricular fibrillation; ventricular tachycardia | Inhibits norepinephrine release from sympathetic nerve endings; increased fibrillation threshold | Worsening of arrhythmia; tachycardia and increased BP initially; nausea, vomiting; hypotension later |
| NURSING IMPLICATIONS: Monitor BP and cardiac status closely; rotate IM injection sites; no more than 5 mL/site | |||
| Diphenylhydantoin (Dilantin)—PO 100–200 mg 3–4 times daily; IV loading dose 10–15 mg/kg (not to exceed 50 mg/min), 50–100 mg over 5–10 min | Digitalis toxicity; ventricular ectopy | Depresses pacemaker activity in sinoatrial (SA) node and Purkinje tissue without slowing conduction velocity | Severe pain if administered in small vein; ataxia, vertigo, nystagmus, seizures, confusion; skin eruptions, hypotension if administered too fast |
| NURSING IMPLICATIONS: With IV use, monitor vital signs; observe for CNS side effects; have O2 on hand; seizure precautions (padded side rails, nonmetal airway; suction, mouth gag); also see Anticonvulsants | |||
| Lidocaine HCl—IV 50–100 mg, bolus; 1–4 mg/kg/min, IV drip | Ventricular tachycardia; premature ventricular contractions (PVCs) | Depresses myocardial response to abnormally generated impulses | Drowsiness, dizziness, nervousness, confusion, paresthesias |
| NURSING IMPLICATIONS: Monitor vital signs; observe for signs of CNS toxicity; monitor ECG for prolonged P-R interval | |||
| Metoprolol tartrate (Lopressor)—PO 25 mg/day; range 25–300 mg/day | Hypertension; angina; MI | Beta-adrenergic blocker; ↓ cardiac output (CO), ↓ heart rate (HR) | Dizziness, fatigue, insomnia; bradycardia, shortness of breath (SOB) |
| NURSING IMPLICATIONS: Monitor: vital signs carefully; I&O, daily weight; check for rales. Give with or without food—be consistent | |||
| Procainamide HCI (Pronestyl)—PO, IM 500–1,000 mg 4–6 times daily; IV 1 gm | Atrial and ventricular arrhythmias; PVCs; overdose of digitalis; general anesthesia | Depresses myocardium; lengthens conduction time between atria and ventricles | Polyarthralgia; fever, chills, urticaria; nausea, vomiting; psychoses; rapid decrease in BP |
| NURSING IMPLICATIONS: Check pulse rate before giving; monitor heart action during IV administration | |||
| Propranolol HCI (Inderal)—IV push 0.5–3.0 mg (up to 3 mg); PO 20–60 mg 3–4 times daily | Ventricular ectopy; angina unresponsive to nitrites, paroxysmal atrial tachycardia (PAT); hypertension | Beta-adrenergic blocker, ↓ cardiac contractility, ↓ heart rate, ↓ myocardial oxygen requirements | Bradycardia, hypotension, vertigo, paresthesia of hands |
| NURSING IMPLICATIONS: Instruct client to take pulse before each dose; do not give to clients with history of asthma or chronic obstructive pulmonary disease; no smoking, because hypertension may occur | |||
| Quinidine SO4—PO 0.2–0.6 gm q2h loading dose; maintenance: 400–1,000 mg 3–4 times daily; IV 5–10 mg/kg over 30–60 min | Atrial fibrillation; PAT; ventricular tachycardia; PVCs | Lengthens conduction time in atria and ventricles; blocks vagal stimulation of heart | Nausea, vomiting, diarrhea; vertigo, tremor, headache; abdominal cramps; AV block, cardiac arrest |
| NURSING IMPLICATIONS: Count pulse before giving; report changes in rate, quality, or rhythm; give drug with food ; monitor BP daily | |||