Betapace Dosage

General Safety Measures for Initiation of Oral Sotalol Therapy

Withdraw other antiarrhythmic therapy before starting Betapace/Betapace AF and monitor for a minimum of 2 to 3 plasma half-lives prior to initiating Betapace/Betapace AF therapy if the patient's clinical condition permits [see Drug Interactions (7)].

Hospitalize patients being initiated or re-initiated on sotalol for at least 3 days or until steady-state drug levels are achieved, in a facility that can provide cardiac resuscitation and continuous electrocardiographic monitoring. Initiate oral sotalol therapy in the presence of personnel trained in the management of serious arrhythmias. Perform a baseline ECG to determine the QT interval and measure and normalize serum potassium and magnesium levels before initiating therapy. Measure serum creatinine and calculate an estimated creatinine clearance in order to establish the appropriate dosing interval. Monitor QTc 2 to 4 hours after each uptitration in dose.

Discharge patients on sotalol therapy from an in-patient setting with an adequate supply of sotalol to allow uninterrupted therapy until the patient can fill a sotalol prescription.

Advise patients who miss a dose to take the next dose at the usual time. Do not double the dose or shorten the dosing interval.

Adult Dose for Ventricular Arrhythmias

The recommended initial dose is 80 mg twice daily. This dose may be increased in increments of 80 mg per day every 3 days provided the QTc <500 msec [see Warnings and Precautions (5.1)]. Continually monitor patients until steady state blood levels are achieved. In most patients, a therapeutic response is obtained at a total daily dose of 160 to 320 mg/day, given in two or three divided doses. Oral doses as high as 480 to 640 mg/day have been utilized in patients with refractory life-threatening arrhythmias.

Adult Dose for Prevention of Recurrence of AFIB/AFL

The recommended initial dose is 80 mg twice daily. This dose may be increased in increments of 80 mg per day every 3 days provided the QTc <500 msec [see Warnings and Precautions (5.1)]. Continually monitor patients until steady state blood levels are achieved. Most patients will have satisfactory response with 120 mg twice daily. Initiation of sotalol in patients with QTc >450 msec is contraindicated [see Contraindication (4)].

Pediatric Dose for Ventricular Arrhythmias or AFIB/AFL

Use the same precautionary measures for children as you would use for adults when initiating and re-initiating sotalol treatment.

For Children Aged About 2 Years and Older

For children aged about 2 years and older, with normal renal function, doses normalized for body surface area are appropriate for both initial and incremental dosing. Since the Class III potency in children is not very different from that in adults, reaching plasma concentrations that occur within the adult dose range is an appropriate guide [see Clinical Pharmacology (12.1, 12.3)].

For initiation of treatment, 1.2 mg/kg three times a day (3.6 mg/kg total daily dose) is approximately equivalent to the initial 160 mg total daily dose for adults. Subsequent titration to a maximum of 2.4 mg/kg three times a day (approximately equivalent to the 360 mg total daily dose for adults) can then occur. Titration should be guided by clinical response, heart rate, and QTc, with increased dosing being preferably conducted in-hospital. Allow at least 36 hours between dose increments to attain steady-state plasma concentrations of sotalol in patients with age‑adjusted normal renal function.

For Children Aged About 2 Years or Younger

For children aged about 2 years or younger, the pediatric dosage should be reduced by a factor that depends upon age, as shown in the following graph (age plotted on a logarithmic scale in months):

For a child aged 1 month, multiply the starting dose by 0.7; the initial starting dose would be (1.2 mg/kg X 0.7)=0.8 mg/kg, administered three times daily. For a child aged about 1 week, multiply the initial starting dose by 0.3; the starting dose would be (1.2 mg/kg X 0.3)=0.4 mg/kg. Use similar calculations for dose titration.

Dosage for Patients with Renal Impairment

Adults

In any age group with decreased renal function, sotalol doses should be lowered or the intervals

between doses increased. It will take much longer to reach steady-state with any dose and/or frequency of administration. Closely monitor heart rate and QTc.

Dose escalations in renal impairment should be done after administration of at least 5 doses at appropriate intervals (Table 1). Sotalol is partly removed by dialysis; specific advice is unavailable on dosing patients on dialysis.

Administer the initial dose of 80 mg and subsequent doses at the intervals listed in Table 1.

Preparation of Extemporaneous Oral Solution

Betapace/Betapace AF Syrup 5 mg/mL can be compounded using Simple Syrup containing 0.1% sodium benzoate (Syrup, NF) as follows:

1.

Measure 120 mL of Simple Syrup.

2.

Transfer the syrup to a 6-ounce amber plastic (polyethylene terephthalate [PET]) prescription bottle. An oversized bottle is used to allow for a headspace, so that there will be more effective mixing during shaking of the bottle.

3.

Add five (5) Betapace/Betapace AF 120 mg tablets to the bottle. These tablets are added intact; it is not necessary to crush the tablets. The addition of the tablets can also be done first. The tablets can also be crushed, if preferred. If the tablets are crushed, take care to transfer the entire quantity of tablet powder into the bottle containing the syrup.

4.

Shake the bottle to wet the entire surface of the tablets. If the tablets have been crushed, shake the bottle until the endpoint is achieved.

5.

Allow the tablets to hydrate for at least two hours.

6.

After at least two hours have elapsed, shake the bottle intermittently over the course of at least another two hours until the tablets are completely disintegrated. The tablets can be allowed to hydrate overnight to simplify the disintegration process.

The endpoint is achieved when a dispersion of fine particles in the syrup is obtained.

This compounding procedure results in a solution containing 5 mg/mL of sotalol HCl. The fine solid particles are the water-insoluble inactive ingredients of the tablets.

Stability studies indicate that the suspension is stable for three months when stored at 15°C to 30°C (59°F to 86°F) [see USP Controlled Room Temperature] and ambient humidity.