AMIODARONE

“CORDARONE”

1) Action

• Class Ia, II, III & IV antiarrhythmic [Mixed]

2) Mechanism

• Blocker of sodium & calcium channels

• Non competitive blocker of beta adrenoreceptors

• Prolongs AP duration & hence refractory period of atrial nodal & ventricular tissues

• Slows sinus rate & AV conduction

• Antianginal effects from its noncompetitive alpha & beta adrenoreceptor properties & calcium channel blockage in coronaries

3) Indications

• Tachyarrhythmias (WPW, supraventricular, nodal, ventricular, AF & Af, VF)

4) Effects on organs—side effects

• Peripheral vasodilation via alpha blocking & calcium channel blockage

5) Toxic effects/ precautions with administration

• Caution in heart failure

• Caution when given to patients on beta blockers of calcium channel antagonists as may exacerbate bradycardias

• Overdosage may lead to circulatory collapse or heart blocks

• Thyroid dysfunction occurs in 5% of patients

6) Contraindications

• Circulatory collapse, hypotension

7) Reversal, antagonism or antidote

• Treat bradycardias with beta agonist or glucagon

8) Loading dose, maintenance dose, frequency & method of administration

• Oral or IV

• 150mg/3 ml ampoules

• 5 mg/Kg iv / 20 minutes ideally CVC

• Emergency: 150-300 mg in 10—20ml over several minutes

9) Drug’s metabolism—Drug’s excretion—Half life (pharmacokinetics)

• Very long half life [13—103 days]

10) Important drug interactions

• Incompatible with saline; use 5% dextrose