Amiodarone and Dronedarone

Question 1

Amiodarone and Dronedarone Class Activity

Answer 1

Ib, II, and IV class activity in addition to class III actions

Question 2

Amiodarone Adverse Effects

Answer 2

Pulmonary fibrosis,
hyper/hypo thyroidism hypothyroidism,
neurologic toxicity
photosensitivity, corneal deposits, hepatitis,
blue-gray skin ,

Question 3

Amiodarone Contraindications

Answer 3

Iodine hypersensitivity, hyperthyroidism,
third-degree AV heart block

Question 4

Amiodarone PK

Answer 4

Half-life 58 days (avg)
Inhibits

Question 5

Amiodarone
Drug Interactions

Answer 5

Warfarin, digoxin, statins (max simvastatin dose 20 mg/day), phenytoin ↑ ≥ 50%, lidocaine,

Question 6

Amiodarone AF Dosing

Answer 6

AF conversion:
IV: 5–7 mg/kg IV over 30–60 min, then 1.2–1.8 g/day continuous IV or divided oral doses until 10 g
PO: 1.2–1.8 g/day in divided doses until 10 g AF maintenance: 200–400 mg/day PO

Question 7

Amiodarone VT/VF Dosing

Answer 7

300 mg or 5 mg/kg IVB; repeat 150 mg IVB every 3–5 min
Stable VT: 150 mg IVB for 10 min
VT/VF maintenance: 1 mg/min × 6 hr, then 0.5 mg/min (max 2.2 g/day)

Question 8

Dronedarone Adverse Effects

Answer 8

Worsening HF, QT prolongation,
hypokalemia or hypomagnesemia with
K+-sparing diuretics, hepatic failure

Question 9

Dronedarone
Contraindications

Answer 9

QTc ≥ 500 ms or PR ≥ 280 ms, NYHA class
IV HF or NYHA class II–III HF with recent
ADHF, severe hepatic impairment, second- or
third-degree AVB, or HR < 50 beats/min

Question 10

Dronedarone PK

Answer 10

Half-life 13–19 hr

Question 11

Dronedarone Drug Interactions

Answer 11

CYP3A4 inhibitors, QT-prolonging drugs,
simvastatin, tacrolimus/sirolimus, warfarin, and other CYP3A4 substrates with narrow, therapeutic range, digoxin and other P-gp substrates (dabigatran, rivaroxaban)

Question 12

Dronedarone
(Multaq) Dosing

Answer 12

AF maintenance: 400 mg orally BID
d/c if QTc ≥ 500 ms