Amiodarone

Nursing pharmacology study reference (NCLEX-style monograph). Numeric values are standard teaching ranges for study and must be verified against current manufacturer labeling before clinical use. This is educational content, not prescribing guidance.

Amiodarone (brand name Pacerone) — Antiarrhythmic; Class III antiarrhythmic.

Identification

• Therapeutic class: Antiarrhythmic.
• Pharmacologic class: Class III antiarrhythmic.

Pharmacology

• Mechanism of action: Prolongs the cardiac action potential and refractory period through multiple channel effects, stabilizing serious arrhythmias.
• Onset / peak / duration: PO onset delayed (days to weeks); IV onset within hours; very long duration.
• Half-life / therapeutic level: Half-life extremely long, about 40 to 55 days; no routine therapeutic level.

Clinical use

• Indications: Life-threatening ventricular arrhythmias, atrial fibrillation.
• Usual dose, route, frequency: Loading then 100 to 400 mg PO daily; IV loading and infusion for acute use.
• Maximum dose / adjustments: Use lowest effective maintenance dose; numerous long-term toxicities require monitoring.

Safety

• Contraindications: Severe sinus node dysfunction, second or third degree block without pacemaker, cardiogenic shock, iodine hypersensitivity.
• Black box warning: Reserved for life-threatening arrhythmias because of risk of pulmonary toxicity, hepatotoxicity, and proarrhythmia.
• Interactions: Warfarin (raises INR), digoxin (raises level), statins (myopathy), many QT-prolonging drugs, grapefruit juice (food).
• Pregnancy / lactation: Avoid unless essential.
• High-alert: IV form warrants extra caution.

Adverse effects

• Common side effects: Bradycardia, hypotension, nausea, photosensitivity, blue-gray skin discoloration.
• Serious effects to report: Pulmonary fibrosis (cough, dyspnea), thyroid dysfunction, hepatotoxicity, severe bradycardia, vision changes.
• Antidote / reversal: None; supportive care.

Nursing process

• Assessment before administration: ECG, blood pressure, baseline thyroid, liver, and pulmonary function, eye history.
• Interventions during therapy: Use a filter and central line for IV when possible; continuous ECG for IV.
• Monitor: ECG and QT interval, thyroid function, LFTs, chest imaging and pulmonary function, eye exams.
• Evaluation / expected outcome: Controlled arrhythmia.

Patient teaching

• Patient teaching: Use sun protection; report cough or breathlessness; expect long-term monitoring.
• Notify provider if: New cough or shortness of breath, vision changes, yellowing of skin, weight or energy changes.
• Administration tips: Consistent timing; avoid grapefruit; protect skin from sun.