Sotalol is an ethanolamine derivative with Class III antiarrhythmic and antihypertensive properties. Sotalol is a nonselective beta-adrenergic receptor and potassium channel antagonist. In the heart, this agent inhibits chronotropic and inotropic effects thereby slowing the heart rate and decreasing myocardial contractility. This agent also reduces sinus rate, slows conduction in the atria and in the atrioventricular (AV) node and increases the functional refractory period of the AV node.
The U.S. Food and Drug Administration (FDA) advises that sotalol only is used for serious abnormal heart rhythms because its prolongation of the QT interval carries a small risk of life-threatening polymorphic ventricular tachycardia known as torsade de pointes. Sotalol is a non-selective competitive beta-adrenergic receptor blocker that also exhibits Class III antiarrhythmic properties.
Mechanism of Action of Sotalol
Sotalol has both beta-adrenoreceptor blocking (Vaughan Williams Class I) and cardiac action potential duration prolongation (Vaughan Williams Class I) antiarrhythmic properties. Sotalol is a racemic mixture of d- and l-sotalol. Both isomers have similar Class I antiarrhythmic effects, while the l-isomer is responsible for virtually all of the beta-blocking activity. Sotalol inhibits the response to adrenergic stimuli by competitively blocking β1-adrenergic receptors within the myocardium and β2-adrenergic receptors within bronchial and vascular smooth muscle. The electrophysiologic effects of sotalol may be due to its selective inhibition of the rapidly activating component of the potassium channel involved in the repolarization of cardiac cells. The class II electrophysiologic effects are caused by an increase in sinus cycle length (slowed heart rate), decreased AV nodal conduction, and increased AV nodal refractoriness, while the class III electrophysiological effects include prolongation of the atrial and ventricular monophasic action potentials, and effective refractory period prolongation of atrial muscle, ventricular muscle, and atrio-ventricular accessory pathways (where present) in both the anterograde and retrograde directions.
Indications of Sotalol
- Atrial Flutter
- Nonvalvular Atrial Fibrillation
- Severe ventricular arrhythmias
- Treatment of documented life-threatening ventricular arrhythmias.
- Atrial Fibrillation
- Ventricular Arrhythmia
- Also for the maintenance of normal sinus rhythm [delay in time to recurrence of atrial fibrillation/atrial flutter (AFIB/AFL)] in patients with symptomatic AFIB/AFL who are currently in sinus rhythm. Also for the treatment of documented life-threatening ventricular arrhythmias.
Contra-Indications of Sotalol
- Diabetes
- Low amount of magnesium in the blood
- Complete heart block
- Second-degree atrioventricular heart block
- Very rapid heartbeat – torsades de pointes
- Sick sinus syndrome
- Sinus bradycardia
- Prolonged QT interval on EKG
- Suddenly serious symptoms of heart failure
- Abnormal EKG with QT changes from Birth
- Abnormally low blood pressure
- Asthma
- Bronchospasm
- Blood Circulation Failure due to Serious Heart Condition
- Pregnancy
- Moderate to severe kidney impairment
- Anaphylactic Shock due to Allergy Shots
- Allergies to Beta-Blockers (Beta-Adrenergic Blocking Agents)
Dosage of Sotalol
Strengths: 120 mg; 80 mg; 160 mg; 240 mg; AF 80 mg; AF 120 mg; AF 160 mg; 5 mg/mL; 15 mg/mL
Atrial Fibrillation
Sotalol: Atrial fibrillation, Ventricular Arrhythmia
- Initial dose: 80 mg orally 2 times a day
- Doses should be adjusted gradually every 3 days in order to attain steady state plasma concentrations and allow for monitoring of QT intervals.
- Maintenance dose: The initial dose may be increased, if needed, to 240 or 320 mg orally per day (120 to 160 mg orally 2 times a day).
- Some patients with life-threatening refractory ventricular arrhythmias may require 480 to 640 mg per day in divided doses.
Oral: Betapace AF (R) Atrial fibrillation
-(STEP 1) Electrocardiographic assessment: Prior to administration of the first dose, the CrCl and the QT interval should be determined. If the baseline QT is greater than 450 msec, Betapace AF (R) is contraindicated:
STEP – 2
- Calculate the CrCl for the patient.
STEP – 3
Initial dose
- If the CrCl is less than 40 mL/day: Betapace AF (R) is contraindicated
- If the CrCl is 40 to 60 mL/min: 80 mg once a day
- If the CrCl is greater than 60 mL/min: 80 mg orally 2 times a day
STEP – 4
- Continuous ECG monitoring with QT interval measurements should begin after the first dose and every 2 to 4 hours after each additional dose.
STEP – 5
- If the 80 mg dose level is tolerated and the QT interval remains less than 500 msec after at least 3 days (after 5 or 6 doses if patient receiving once-daily dosing), the patient can be discharged. Alternatively, during hospitalization, the dose can be increased to 120 mg twice daily and the patient followed for 3 days on this dose (followed for 5 or 6 doses if patient receiving once-daily dosing).
- If the 80 mg dose level (given twice a day or once-daily depending upon CrCl) does not reduce the frequency of relapses of atrial fibrillation/atrial flutter and is tolerated without excessive QT interval prolongation (i.e., greater than or equal to 520 msec), the dose level may be increased to 120 mg (twice a day or once-daily depending upon CrCl).
- If the 120 mg dose does not reduce the frequency of early relapse of atrial fibrillation/atrial flutter and is tolerated without excessive QT interval prolongation (greater than or equal to 520 msec), an increase to 160 mg (2 times a day or daily) depending upon CrCl), can be considered.
- Any increases in dosage should be done in a step-wise fashion as outlined above.
- Maintenance dose: 120 to 160 mg orally 2 times a day. Renal function and QT should be reevaluated regularly if medically warranted. If QT is 520 msec or greater (JT 430 msec or greater if QRS is greater than 100 msec), the dose should be reduced and patients should be carefully monitored until QT returns to less than 520 msec. If the QT interval is greater than or equal to 520 msec while on the lowest maintenance dose level (80 mg) the drug should be discontinued.
Parenteral
- Initial: 112.5 mg IV once or twice daily
- Maintenance: 112.5 to 150 mg IV once or twice daily
- If 112.5 mg IV once or twice daily, at steady state, does not reduce the frequency of early relapse of arrhythmia and is tolerated without excessive QTc prolongation (greater than 520 msec), increase the dose to 150 mg IV once or twice daily.
- Start IV therapy only if the baseline QT interval is less than 450 msec. During initiation and titration, monitor the QT interval after the completion of each infusion. If the QT interval prolongs to 500 msec or greater, reduce the dose, decrease the infusion rate, or discontinue the drug.
Ventricular Arrhythmia
Usual Adult Dose: Ventricular Arrhythmia (CA, US):
Sotalol: Atrial fibrillation, Ventricular Arrhythmia
- Initial dose: 80 mg orally 2 times a day
- Doses should be adjusted gradually every 3 days in order to attain steady state plasma concentrations and allow for monitoring of QT intervals.
- Maintenance dose: The initial dose may be increased, if needed, to 240 or 320 mg orally per day (120 to 160 mg orally 2 times a day).
- Some patients with life-threatening refractory ventricular arrhythmias may require 480 to 640 mg per day in divided dose
Oral: Betapace AF (R) Atrial fibrillation
- Initial: 80 mg twice daily
- The initial dose may be increased 120 to 160 mg twice daily. The dosage should be adjusted gradually allowing 3 days between dosing increments in order to attain steady-state plasma concentrations and to allow monitoring of QT intervals. Graded dose adjustment will help prevent doses that are higher than necessary to control the arrhythmia. Most patients obtain a therapeutic response with a total daily dose of 160 to 320 mg given in two or three divided doses.
Parenteral
- Initial: 75 mg IV infused over 5 hours once or twice daily based on the creatinine clearance.
- Maintenance: 75 to 300 mg infused over 5 hours once or twice daily based on the creatinine clearance.
- The dose may be increased in increments of 75 mg/day every 3 days. Doses as high as 225 or 300 mg IV have been utilized in patients with refractory life-threatening arrhythmias.
- Start IV therapy only if the baseline QT interval is less than 450 msec. During initiation and titration, monitor the QT interval after the completion of each infusion. If the QT interval prolongs to 500 msec or greater, reduce the dose, decrease the infusion rate, or discontinue the drug.
Side Effects of Sotalol
The most common
- Blurred vision
- chest pain or discomfort
- confusion
- difficult or labored breathing
- dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
- Burning, crawling, itching, numbness, prickling, “pins and needles”, or tingling feelings
- Shortness of breath
- Chest pain or discomfort
- Slow or irregular heartbeat
- Dry mouth/ a cough
- muscle trembling, jerking, or stiffness
- anxiety
- changes in vision, including blurred vision
- dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
- stomach pain or cramping
- diarrhea
- a headache
- stomach pain;
- back pain, joint or muscle pain.
- problems with your vision (including color vision);
- sudden chest pain or trouble breathing;
- pain or swelling in one or both legs;
- a migraine headache;
- pale skin, feeling light-headed or short of breath, rapid heart rate, trouble concentrating; or
More common
- Abdominal or stomach pain, discomfort, or tenderness
- chills or fever
- difficulty with moving
- a headache, severe and throbbing
- joint or back pain
- muscle aching or cramping
- muscle pains or stiffness
- chest pressure or squeezing pain in the chest
- discomfort in arms, shoulders, neck or upper back
- excessive sweating
- feeling of heaviness, pain, warmth and/or swelling in a leg or in the pelvis
- sudden tingling or coldness in an arm or leg
- sudden slow or difficult speech
- sudden drowsiness or need to sleep
- fast breathing
- sharp pain when taking a deep breath
- fast or slow heartbeat
- coughing up blood
- rust colored urine
- decreased amount of urine
Rare
- Anxiety
- change in vision
- chest pain or tightness
- confusion
- a cough
- Agitation
- arm, back, or jaw pain
- blurred vision
- chest pain or discomfort
- convulsions
- extra heartbeats
- fainting
- hallucinations
- a headache
- irritability
- lightheadedness
- mood or mental changes
- muscle pain or cramps
- muscle spasm or jerking of all extremities
- nervousness
Drug Interactions of Sotalol
Sotalol may interact with the following drug, supplements, & may change the efficacy of the drug
- aluminum salts (e.g., aluminum hydroxide, attapulgite, kaolin)
- anti-arrhythmias (e.g., disopyramide, flecainide, procainamide, quinidine)
- beta-blockers (e.g., metoprolol, propranolol)
- calcium channel blockers (e.g., diltiazem, verapamil)
- diuretics (water pills) that cause potassium loss (e.g., hydrochlorothiazide)
- erythromycin
- lidocaine
- phenothiazines (e.g., chlorpromazine, perphenazine)
- prazosin
- quinolone antibiotics (e.g., ciprofloxacin, levofloxacin)
- salbutamol
- terfenadine
- tricyclic antidepressants (e.g., amitriptyline, desipramine)
Pregnancy Catagory of Sotalol
FDA Pregnancy Category B
Pregnancy
This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Lactation
This medication passes into breast milk. If you are a breastfeeding mother and are taking sotalol, it may affect your baby. Talk to your doctor about whether you should continue breastfeeding.The safety and effectiveness of using sotalol have not been established for children and adolescents under 18 years of age.
References
- https://www.drugs.com/mtm/sotalol.html
- https://www.webmd.com/drugs/2/drug-8848/sotalol-oral/details/list-contraindications
