DOFETILIDE ALGORITHM
DOFETILIDE IS CONTRAINDICATED IF:
(A) BASELINE QTc IS > 440 MSEC
(or > 500 msec in patients with ventricular
conduction abnormalities)
(B) CLCr < 20 mL/min
****ALGORITHM***
1. Determine CLCr:
*Male Creatinine Clearance =
(140-age) x actual body weight in kg
72 x serum creatinine (mg/dL)
*Female creatinine clearance =
(140 - age) x actual body weight in kg x 0.85
72 x serum creatinine
2. First Dose
CLCr > 60 mL/min: ----> 500 mcg BID
CLCr = 40-60 mL/min: -----> 250 mcg BID
CLCr = 20-40 mL/min: -----> 125 mcg BID
3. Get ECG 2-3 Hours after 1st Dose
4. Second Dose (give ONLY after calculating QTc)
-If QTc increases < 15% and QTc < 500 msec ---> Good to go!
-If QTc increases > 15% or QTC > 500 msec (or 550 msec in ventricular conduction abnormality):
CLCr > 60 mL/min ----> 250 mcg po BID
CLCr = 40-60 mL/min: ----> 125 mcg po BID
CLCr = 20-40 mL/min: ----> 125 mcg po DAILY
5. Beyond 2nd Dose (3rd dose and everything after)
-If QTc still > 500 msec (or 550 msec in presence of ventricular conduction abnormality) --> DISCONTINUE!!!
-OBTAIN ECG 2-3 HOURS AFTER EACH DOSE UNTIL THE PATIENT IS DISCHARGED-
OTHER TIPS:
*If Potassium (K+) < 4.0 mEq/L, replace prior to giving Dofetilide
*Get ECG and Renal Function q 3 months
*Hold Previous Antiarrhythmics for at least 3 plasma half lives
-Amiodarone should be withheld for at least 3 months or when amiodarone levels < 0.3 mcg/ml
DRUGS TO AVOID
-Verapamil
-Cimetidine
-HCTZ
-Ketoconazole
-Trimethoprim/Sulfamethoxazole
-Prochlorperazine
-Megestrol
-Dolutegravir
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DOFETILIDE LOADING INSTRUCTIONS:
PRE-LOADING CHECK:
DOFETILIDE IS CONTRAINDICATED IF:
(A) BASELINE QTc IS > 440 MSEC (or > 500 msec in patients with
ventricular conduction abnormalities)
(B) CLCr < 20 mL/min
STEP ONE: Determine CLCr:
*Male Creatinine Clearance = (140-age) x actual body weight in kg
72 x serum creatinine (mg/dL)
*Female creatinine clearance = (140-age) x actual body wt in kg x 0.85
72 x serum creatinine
STEP TWO: Give First Dose
CLCr > 60 mL/min: ----> 500 mcg BID
CLCr = 40-60 mL/min: -----> 250 mcg BID
CLCr = 20-40 mL/min: -----> 125 mcg BID
STEP THREE: Get ECG 2-3 Hours after 1st Dose
STEP FOUR: Give Second Dose (give ONLY after calculating QTc)
-If QTc increases < 15% and QTc < 500 msec ---> Good to go!
-If QTc increases > 15% or QTC > 500 msec (or 550 msec in ventricular
conduction abnormality):
CLCr > 60 mL/min ----> 250 mcg po BID
CLCr = 40-60 mL/min: ----> 125 mcg po BID
CLCr = 20-40 mL/min: ----> 125 mcg po DAILY
STEP FIVE: Beyond 2nd Dose (3rd dose and everything after)
-If QTc still > 500 msec (or 550 msec in presence of ventricular
conduction abnormality) --> DISCONTINUE!!!
***OBTAIN ECG 2-3 HOURS AFTER EACH DOSE UNTIL THE PATIENT IS DISCHARGED***
OTHER TIPS:
*If Potassium (K+) < 4.0 mEq/L, replace prior to giving Dofetilide
*Get ECG and Renal Function q 3 months
*Hold Previous Antiarrhythmics for at least 3 plasma half lives
-Amiodarone should be withheld for at least 3 months or when amiodarone
levels < 0.3 mcg/ml
DRUGS TO AVOID
-Verapamil
-Cimetidine
-HCTZ
-Ketoconazole
-Trimethoprim/Sulfamethoxazole
-Prochlorperazine
-Megestrol
-Dolutegravir