am-ee-OH-da-rone
BEERS REMS, High Alert
Absorption: Slowly and variably absorbed from the GI tract (35–65%). IV administration results in complete bioavailability.
Distribution: Distributed to and accumulates slowly in body tissues. Reaches high levels in fat, muscle, liver, lungs, and spleen.
Protein Binding: 96%.
Half-Life: 13–107 days.
(suppression of ventricular arrhythmias)
| ROUTE | ONSET | PEAK | DURATION |
|---|---|---|---|
| PO | 2–3 days (up to 2–3 mo) | 3–7 hr | wk–mos |
| IV | 2 hr | 3–7 hr | unknown |
Contraindicated in:
Use Cautiously in:
CV: bradycardia, hypotension, HF, QT interval prolongation, WORSENING VENTRICULAR ARRHYTHMIAS
Derm: photosensitivity, blue discoloration
EENT: corneal microdeposits, abnormal sense of smell, dry eyes, optic neuritis, optic neuropathy, photophobia
Endo: hypothyroidism, hyperthyroidism
GI: anorexia, constipation, nausea, vomiting, ↑liver enzymes, abdominal pain, abnormal sense of taste, HEPATOTOXICITY
GU: ↓libido, epididymitis
Neuro: ataxia, dizziness, fatigue, involuntary movement, malaise, paresthesia, peripheral neuropathy, poor coordination, tremor, confusional states, disorientation, hallucinations, headache, insomnia
Resp: ACUTE RESPIRATORY DISTRESS SYNDROME, PULMONARY FIBROSIS
Drug-drug:
Drug-Natural Products:
Drug-Food:
Ventricular Arrhythmias
Monitor ECG continuously during IV therapy or initiation of oral therapy. Monitor HR and rhythm throughout therapy; PR prolongation, slight QRS widening, and T-wave amplitude reduction with T-wave widening and bifurcation may occur. QT interval prolongation may be associated with worsening of arrhythmias; monitor closely during IV therapy. Report bradycardia or ↑ in arrhythmias promptly; patients receiving IV therapy may require slowing infusion rate, discontinuing infusion, or inserting a temporary pacemaker.
Assess for signs of pulmonary toxicity (rales/crackles, ↓ breath sounds, pleuritic friction rub, fatigue, dyspnea, cough, wheezing, pleuritic pain, fever, hemoptysis, hypoxia). Chest x-ray and pulmonary function tests are recommended before therapy. Monitor chest x-ray yearly during therapy to detect diffuse interstitial changes or alveolar infiltrates. Bronchoscopy or gallium radionuclide scan may also be used for diagnosis. Usually reversible after withdrawal, but fatalities have occurred.
Lab Test Considerations:
Monitor AST and ALT before starting therapy and every 6 mo during therapy. If liver function studies are 3 times the upper limit of normal or double in patients with elevated baseline levels or if hepatomegaly occurs,↓ dose.
IV Administration: