Amiodarone Flashcards
Half life
- Amiodarone has a long half-life of about 50 days
- Loading doses may be required
Monitoring
Thyroid function, liver function, serum potassium, chest X-ray, ECG (with intravenous use)
Warning Signs
• Signs and symptoms of hypo- or hyperthyroidism
• Corneal microdeposits may develop but these rarely interfere with vision. Drivers may be
dazzled by headlights at night. If vision impaired or if optic neuritis or optic neuropathy
occur, stop amiodarone
• Progressive shortness of breath or cough (pneumonitis, pulmonary toxicity)
• Clinical signs of liver disease e.g. jaundice
• Neurological effects of tremor, peripheral neuropathy (e.g. develop numbness and tingling in
hands and feet)
• Phototoxic skin reactions e.g. burning sensation followed by erythema, and persistent slate
grey skin discoloration on light-exposed areas
Actions Required
• Advise patient to shield skin from direct sunlight and for several months after stopping
treatment or to use a wide-spectrum sunscreen
• Warn drivers that they may be dazzled by headlights at night
• Warn patients that the clinical effects may occur for a few months after stopping the
medicine
Interactions
• Due to its long half-life, there is potential for drug interactions to occur for several weeks to
months after treatment has been stopped
• Increased plasma concentration of coumarins, dabigatran, digoxin, fecainide, phenindione,
phenytoin
• Increased risk of ventricular arrhythmias when amiodarone given with amisulpride, atomoxetine,
chloroquine, citalopram, disopyramide, escitalopram, haloperidol, hydroxychloroquine,
levofoxacin, lithium, mizolastine, mefoquine, moxifoxacin, phenothiazines, pimozide,
quinine, sulpiride, telithromycin, tolterodine, tricyclics
• Increased risk of bradycardia, AV block and myocardial depression when amiodarone given
with beta-blockers, diltiazem, verapamil
• Increased risk of myopathy when amiodarone given with simvastatin
