Sotacor (Sotalol): Uses, Dosage & Side Effects
Beta-blocker with antiarrhythmic properties for cardiac arrhythmias
Quick Facts About Sotacor
Key Takeaways About Sotacor
- Unique dual mechanism: Sotalol is the only beta-blocker with both Class II (beta-blocking) and Class III (potassium channel blocking) antiarrhythmic properties, making it effective for both rate and rhythm control
- QT prolongation risk: Sotalol prolongs the QT interval in a dose-dependent manner, which can lead to serious proarrhythmic effects including torsades de pointes — ECG monitoring is recommended during initiation
- Do not stop abruptly: Treatment should be tapered gradually over 1–2 weeks under medical supervision to avoid rebound tachycardia, worsening arrhythmias, or angina
- Renal elimination: Sotalol is excreted unchanged by the kidneys, so dose reduction is essential in patients with impaired kidney function
- Take on an empty stomach: Sotacor should be taken at least 1 hour before meals, as food reduces absorption by approximately 20%
What Is Sotacor and What Is It Used For?
Sotacor contains sotalol hydrochloride, a non-selective beta-blocker with additional Class III antiarrhythmic properties. It is used to treat and prevent cardiac arrhythmias including atrial fibrillation, atrial flutter, supraventricular tachycardia, and ventricular tachycardia.
Sotalol occupies a unique position among cardiovascular medications. It is the only beta-blocker that also possesses significant Class III antiarrhythmic activity, giving it a dual mechanism of action that sets it apart from other beta-blockers such as metoprolol, atenolol, and propranolol. This combination makes sotalol particularly versatile in managing cardiac arrhythmias, as it can simultaneously slow the heart rate (through beta-blockade) and stabilize the heart's electrical rhythm (through potassium channel blockade).
As a non-selective beta-adrenergic receptor antagonist (Class II effect), sotalol blocks both beta-1 receptors in the heart and beta-2 receptors in the lungs and blood vessels. This reduces heart rate, decreases the force of cardiac contraction, slows conduction through the atrioventricular (AV) node, and lowers blood pressure. Unlike selective beta-blockers, sotalol's non-selective nature means it also affects the airways, which is why it is contraindicated in patients with asthma or severe bronchospasm.
The Class III antiarrhythmic effect arises from sotalol's ability to block delayed rectifier potassium channels (IKr channels). This prolongs the cardiac action potential duration and the effective refractory period in atrial, ventricular, and accessory pathway tissue. By extending the time during which the heart muscle cells are unable to fire again, sotalol reduces the likelihood of re-entrant circuits — the most common mechanism underlying sustained cardiac arrhythmias.
Sotacor is primarily prescribed for the following conditions:
- Atrial fibrillation (AF) — the most common sustained cardiac arrhythmia, characterized by rapid, irregular electrical activity in the atria. Sotalol is used for both rate control and rhythm control (cardioversion and maintenance of sinus rhythm)
- Atrial flutter (AFL) — a related arrhythmia involving a regular but rapid circuit in the atria
- Supraventricular tachycardia (SVT) — rapid heart rhythms originating above the ventricles, including AV nodal re-entrant tachycardia (AVNRT) and AV re-entrant tachycardia (AVRT)
- Ventricular tachycardia (VT) — an abnormally fast heart rhythm originating in the ventricles, which can be life-threatening and may degenerate into ventricular fibrillation
Sotalol is one of the few antiarrhythmic drugs recommended by the European Society of Cardiology (ESC) as a first-line option for pharmacological cardioversion and maintenance of sinus rhythm in patients with atrial fibrillation who do not have significant structural heart disease. The 2020 ESC guidelines for atrial fibrillation management include sotalol among the recommended agents for rhythm control strategies.
How sotalol differs from other beta-blockers
While all beta-blockers share the ability to reduce heart rate and blood pressure through beta-adrenergic receptor blockade, sotalol is fundamentally different because of its additional potassium channel blocking activity. Standard beta-blockers like metoprolol, atenolol, and bisoprolol are primarily used for rate control in arrhythmias — they slow the heart rate but do not directly prevent the electrical re-entry circuits that sustain arrhythmias. Sotalol, by contrast, addresses both mechanisms: it slows conduction while also prolonging refractoriness, making it effective at terminating and preventing recurrent arrhythmias.
This dual action also distinguishes sotalol from pure Class III antiarrhythmic drugs like amiodarone, which has a broader spectrum of electrophysiological effects but also a more complex side effect profile. Sotalol is generally better tolerated than amiodarone for long-term use in appropriate patients, though it lacks amiodarone's effectiveness in certain refractory arrhythmias and has a higher proarrhythmic potential at higher doses.
What Should You Know Before Taking Sotacor?
Sotacor should not be used if you have asthma, untreated heart failure, cardiogenic shock, severe bradycardia, certain heart conduction disorders, congenital or acquired long QT syndrome, untreated pheochromocytoma, severe kidney impairment, or metabolic acidosis. Several medications must be avoided due to the risk of dangerous heart rhythm disturbances.
Before starting treatment with Sotacor, your physician will conduct a thorough medical evaluation including an ECG, assessment of kidney function (as sotalol is eliminated entirely by the kidneys), and measurement of blood electrolytes (particularly potassium and magnesium). Understanding the contraindications and precautions is essential for the safe use of this medication.
Contraindications
Sotacor must not be used in the following situations:
- Allergy to sotalol or any of the excipients listed in the product
- Asthma or history of severe bronchospasm — sotalol is a non-selective beta-blocker and can trigger life-threatening bronchospasm
- Certain heart conduction disorders — second- or third-degree AV block, sick sinus syndrome, or sinoatrial block (unless a permanent pacemaker is in place)
- Untreated or decompensated heart failure — sotalol can worsen cardiac output in uncontrolled heart failure
- Cardiogenic shock
- Untreated pheochromocytoma — beta-blockade without prior alpha-blockade can cause a hypertensive crisis
- Clinically significant hypotension (low blood pressure)
- Severe peripheral circulatory disorders — including Raynaud's phenomenon with severe symptoms
- Severe renal impairment — sotalol is excreted unchanged by the kidneys and accumulates dangerously in severe kidney disease
- Metabolic acidosis
- Congenital or acquired long QT syndrome — sotalol further prolongs the QT interval and increases the risk of torsades de pointes
- Certain types of general anesthesia that produce myocardial depression (e.g., cyclopropane, trichloroethylene)
Warnings and Precautions
Speak to your doctor before taking Sotacor if you have any of the following conditions or circumstances:
- Diabetes mellitus — sotalol can mask the typical warning signs of hypoglycemia (low blood sugar), particularly tachycardia and tremor. Blood glucose monitoring should be intensified during treatment
- Low potassium or magnesium levels (hypokalemia, hypomagnesemia) — electrolyte imbalances increase the risk of QT prolongation and torsades de pointes. Electrolytes should be corrected before starting sotalol and monitored during treatment
- Impaired renal function — sotalol is eliminated entirely by the kidneys, and dose reduction is mandatory in moderate renal impairment. Creatinine clearance should be determined before starting treatment
- Poor peripheral circulation — sotalol may worsen symptoms of Raynaud's disease or intermittent claudication
- Prinzmetal's angina (variant angina) — beta-blockers may increase the frequency and duration of vasospastic angina episodes
- Psoriasis — beta-blockers may worsen psoriasis in some patients
- History of anaphylactic reactions — beta-blockers may increase the severity of anaphylaxis and reduce the effectiveness of epinephrine (adrenaline) treatment
- Dizziness, fainting, or near-fainting — may indicate excessive QT prolongation, torsades de pointes, or severe bradycardia
- Worsening shortness of breath, swollen ankles, or fatigue — may indicate worsening heart failure
- Very slow heart rate (below 50 beats per minute) with symptoms of weakness or lightheadedness
- Wheezing or difficulty breathing — may indicate bronchospasm, especially in patients with a history of respiratory conditions
Abrupt discontinuation of sotalol can lead to serious rebound effects including worsening arrhythmias, accelerated heart rate, and in patients with coronary artery disease, angina or myocardial infarction. Treatment should be gradually tapered over 1–2 weeks under the supervision of your prescribing physician.
Pregnancy and Breastfeeding
Sotalol crosses the placenta and may affect the fetus. It should only be used during pregnancy when the potential benefit to the mother clearly outweighs the risk to the fetus. Beta-blockers, including sotalol, can cause fetal bradycardia, hypoglycemia, and growth restriction.
If treatment with Sotacor is deemed necessary during pregnancy, the medication should ideally be discontinued 48–72 hours before the expected delivery if clinically feasible. The newborn should be monitored for 48–72 hours after birth for signs of beta-blockade, including bradycardia, hypotension, respiratory depression, and hypoglycemia.
Sotalol passes into breast milk in significant concentrations. Breastfeeding is generally not recommended during treatment unless the prescribing doctor considers the benefit to outweigh the potential risk to the nursing infant. If the infant is breastfed during maternal sotalol therapy, the infant should be monitored for signs of beta-blockade.
Children
The safety and efficacy of Sotacor have not been established in patients under 18 years of age. Use in children should only be considered by a specialist pediatric cardiologist who can carefully weigh the potential benefits against the risks.
Driving and operating machinery
Sotalol usually does not affect the ability to drive or operate machinery. However, particularly at the start of treatment, when doses are changed, or in combination with alcohol, fatigue, dizziness, or visual disturbances may occur. Patients should be aware of these potential effects and avoid driving or operating machinery if affected.
Lactose content
Sotacor tablets contain lactose monohydrate. Patients with rare hereditary problems of galactose intolerance, total lactase deficiency, or glucose-galactose malabsorption should not take this medicine.
How Does Sotacor Interact with Other Drugs?
Sotalol has numerous significant drug interactions, primarily related to its QT-prolonging effect and its beta-blocking activity. Combining sotalol with other QT-prolonging drugs substantially increases the risk of torsades de pointes, a potentially fatal ventricular arrhythmia. Calcium channel blockers, digoxin, and drugs that lower potassium or magnesium also require careful management.
Drug interactions with sotalol are a major clinical concern because the drug prolongs the QT interval in a dose-dependent manner. When combined with other medications that also prolong the QT interval, the risk of dangerous ventricular arrhythmias — particularly torsades de pointes — increases substantially. Additionally, sotalol's beta-blocking activity can interact with many cardiovascular and non-cardiovascular medications.
It is critically important to inform your doctor about all medications you are taking, including over-the-counter drugs and herbal supplements, before starting Sotacor.
Major Interactions — QT Prolongation Risk (Avoid Combination)
Sotacor should not be combined with the following medications due to the additive risk of QT prolongation and torsades de pointes:
| Drug / Class | Risk | Recommendation |
|---|---|---|
| Class I/III antiarrhythmics (disopyramide, flecainide, amiodarone, dronedarone) | Additive QT prolongation, risk of torsades de pointes | Avoid combination — high proarrhythmic risk |
| Antipsychotics (chlorpromazine, thioridazine, haloperidol, amisulpride, pimozide) | QT prolongation, risk of torsades de pointes | Contraindicated — do not combine |
| Certain antidepressants (citalopram, fluoxetine, sertraline, clomipramine, amitriptyline, imipramine, trazodone) | Additive QT prolongation | Avoid combination or use with extreme caution and ECG monitoring |
| Fluoroquinolone antibiotics (ciprofloxacin, levofloxacin, moxifloxacin) | QT prolongation, risk of cardiac arrhythmias | Avoid combination — use alternative antibiotics |
| Macrolide antibiotics (erythromycin, clarithromycin, azithromycin) | QT prolongation | Avoid combination — use alternative antibiotics |
| Antimalarials (mefloquine, chloroquine, halofantrine, quinine) | QT prolongation, bradycardia | Contraindicated — do not combine |
| Anti-emetics (ondansetron, domperidone) | Additive QT prolongation | Use alternatives where possible |
| Opioids (methadone, hydrocodone) | QT prolongation | Avoid combination — use alternatives |
| Pentamidine, ranolazine, arsenic trioxide, anagrelide | QT prolongation | Contraindicated — do not combine |
| Antifungals (fluconazole, amphotericin) | QT prolongation; amphotericin may also lower potassium | Avoid combination or monitor closely |
| Protein kinase inhibitors (sunitinib, vandetanib, sorafenib) | QT prolongation | Avoid combination |
| Antihistamines / Hydroxyzine (chlorphenamine, diphenhydramine, hydroxyzine) | QT prolongation | Use alternatives — second-generation antihistamines preferred |
| Donepezil | QT prolongation, additive bradycardia | Use with caution; ECG monitoring |
Other Important Interactions
The following medications require dose adjustments, increased monitoring, or careful clinical assessment when used with Sotacor:
| Drug / Class | Effect | Action Required |
|---|---|---|
| Calcium channel blockers (verapamil, diltiazem) | Severe bradycardia, AV block, heart failure; combined negative inotropic and chronotropic effects | Avoid combination or use under specialist supervision with close monitoring |
| Digoxin | Additive slowing of AV conduction; increased risk of bradycardia | Monitor heart rate and ECG; dose adjustment may be needed |
| Clonidine | Rebound hypertension if clonidine is stopped abruptly while on beta-blocker | If stopping both, taper beta-blocker first, then clonidine gradually |
| Centrally acting antihypertensives (methyldopa, guanethidine) | Enhanced hypotensive effect, bradycardia | Monitor blood pressure and heart rate closely |
| Insulin and oral hypoglycemics | Sotalol masks hypoglycemia symptoms (tachycardia, tremor); may prolong hypoglycemia | Intensify blood glucose monitoring; educate patient on non-adrenergic hypoglycemia symptoms (sweating) |
| Beta-2 agonists (salbutamol, salmeterol, formoterol) | Sotalol antagonizes bronchodilator effect; increased risk of bronchospasm | Avoid combination in patients with asthma; higher doses of beta-2 agonist may be needed in COPD |
| Potassium-depleting drugs (loop/thiazide diuretics, corticosteroids, stimulant laxatives) | Low potassium increases risk of QT prolongation and torsades de pointes | Monitor electrolytes regularly; correct hypokalemia and hypomagnesemia |
| H2 blockers (cimetidine, famotidine) | Cimetidine may increase sotalol absorption and blood levels | Monitor for enhanced beta-blocker effects |
| Proton pump inhibitors (omeprazole, lansoprazole, esomeprazole) | Potential for reduced sotalol absorption or altered bioavailability | Separate administration times if clinically indicated |
Food interactions
Food reduces the absorption of sotalol by approximately 20%. Sotacor should therefore be taken at least 1 hour before meals to ensure optimal and consistent drug absorption. This is particularly important given the dose-dependent nature of sotalol's QT-prolonging effect — consistent absorption helps maintain predictable blood levels.
Before and during treatment with sotalol, it is essential to maintain normal levels of potassium and magnesium. Low levels of these electrolytes significantly increase the risk of QT prolongation and the dangerous arrhythmia torsades de pointes. Your doctor will monitor your electrolytes, particularly if you are also taking diuretics, corticosteroids, or stimulant laxatives.
What Is the Correct Dosage of Sotacor?
The usual starting dose of Sotacor is 80 mg once daily or divided into two doses. The maintenance dose is typically 160–320 mg per day, divided into two doses. Dosage is individualized based on clinical response and ECG monitoring. Take on an empty stomach at least 1 hour before meals.
Sotalol dosing requires careful individualization, particularly because the QT-prolonging effect is dose-dependent. Treatment should ideally be initiated under medical supervision with continuous ECG monitoring, especially in patients at higher risk for proarrhythmic effects. The goal is to find the lowest effective dose that controls the arrhythmia while minimizing the risk of adverse effects.
Adults — Oral Administration
Starting Dose
The recommended starting dose is 80 mg once daily, which may be given as a single dose or split into two doses of 40 mg. Treatment initiation at a low dose allows assessment of the patient's tolerance and QT interval response before escalation.
Maintenance Dose
The usual maintenance dose is 160–320 mg per day, divided into two equal doses (80–160 mg twice daily). The dose may be gradually increased at intervals of 2–3 days based on clinical response and QT interval assessment. Some patients with severe or refractory arrhythmias may require higher doses, but this should only be determined by a specialist with appropriate monitoring.
Administration
Sotacor tablets should be taken at least 1 hour before meals, as food reduces absorption. The tablets are scored and can be divided for dose adjustment. Swallow with a glass of water.
Dose Adjustment in Renal Impairment
Since sotalol is excreted unchanged by the kidneys, dose reduction is essential in patients with impaired renal function. The dosing interval should be extended based on creatinine clearance:
- Creatinine clearance 30–60 ml/min: Give the normal dose at half the usual frequency (i.e., half the total daily dose, or give normal doses at doubled intervals)
- Creatinine clearance 10–30 ml/min: Give one quarter of the normal dose, with close monitoring
- Creatinine clearance below 10 ml/min: Sotalol is contraindicated due to accumulation risk
Missed Dose
If you miss a dose of Sotacor, take it as soon as you remember. However, if it is nearly time for your next dose, skip the missed dose and continue with your regular schedule. Do not take a double dose to make up for a missed one.
Overdose
In case of suspected overdose, seek immediate medical attention. Symptoms of sotalol overdose may include:
- Severe bradycardia (very slow heart rate)
- Hypotension (dangerously low blood pressure)
- Breathing difficulties (bronchospasm)
- Seizures, including those related to hypoglycemia
- Cardiac conduction disturbances and at very high doses, QT prolongation with risk of torsades de pointes
- Hypoglycemia (low blood sugar), particularly in patients with diabetes
Treatment of sotalol overdose is supportive. Atropine may be used for bradycardia, and in severe cases, temporary cardiac pacing, intravenous glucagon, or isoproterenol (isoprenaline) may be required. Hemodialysis can effectively remove sotalol from the blood due to its low protein binding and primarily renal elimination.
Stopping Treatment
Treatment with Sotacor should never be stopped abruptly. The dose should be gradually tapered over 1–2 weeks under the supervision of your doctor. This is particularly important in patients with coronary artery disease, where sudden withdrawal of beta-blocker therapy can precipitate unstable angina, myocardial infarction, or ventricular arrhythmias. Your physician will create a tapering schedule appropriate for your individual circumstances.
What Are the Side Effects of Sotacor?
Sotalol can cause side effects related to both its beta-blocking activity and its QT-prolonging effect. Very common side effects (affecting more than 1 in 10 patients) include shortness of breath, fatigue, bradycardia, dizziness, headache, nausea, diarrhea, and ECG abnormalities. The most serious potential adverse effect is proarrhythmia, particularly torsades de pointes.
Like all medications, Sotacor can cause side effects, though not everyone experiences them. The side effects of sotalol reflect its dual pharmacological actions: beta-adrenergic blockade (which accounts for fatigue, bradycardia, bronchospasm, cold extremities, and masking of hypoglycemia) and potassium channel blockade (which accounts for QT prolongation and the risk of proarrhythmic effects). Side effects are generally dose-dependent and may improve with dose reduction.
- Dizziness, fainting, or palpitations with a very fast or irregular heartbeat — may indicate torsades de pointes or other proarrhythmic effect
- Severe shortness of breath or wheezing — may indicate bronchospasm
- Worsening fatigue, swollen ankles, or breathlessness on exertion — may indicate worsening heart failure
- Blue or very cold fingers and toes — may indicate severe peripheral circulatory disturbance
Very Common (more than 1 in 10 patients)
- Dyspnea (shortness of breath)
- Chest pain
- Diarrhea
- Palpitations
- Headache
- Fatigue and asthenia (weakness)
- Nausea and vomiting
- Bradycardia (slow heart rate)
- ECG abnormalities (QT prolongation)
- Sleep disturbances (insomnia, vivid dreams)
- Edema (swelling)
- Dizziness
Common (up to 1 in 10 patients)
- Depression
- Paresthesia (tingling or numbness)
- Fever
- Flatulence
- Heart failure
- Arrhythmia (proarrhythmic effect)
- Skin rash
- Mood changes
- Hearing disturbances
- Hypotension (low blood pressure)
- Abdominal pain
- Anxiety
- Sexual dysfunction
- Taste changes
- Dyspepsia (indigestion)
- Syncope (fainting)
- Visual disturbances
- Muscle cramps
Frequency Not Known
- Thrombocytopenia (low platelet count)
- Peripheral circulatory disturbances (cold or blue fingers and toes, intermittent claudication)
- Angina pectoris (chest pain)
- AV block (heart conduction disturbance)
- Bronchospasm (airway constriction)
- Pruritus (itching)
- Alopecia (hair loss)
- Excessive sweating (hyperhidrosis)
- Worsening of psoriasis
- Torsades de pointes (a specific, potentially fatal ventricular arrhythmia)
Proarrhythmic effects — a special concern
The most clinically significant risk of sotalol therapy is its potential to cause or worsen arrhythmias (proarrhythmia). This paradoxical effect is primarily due to excessive QT prolongation, which can trigger torsades de pointes — a polymorphic ventricular tachycardia that can degenerate into ventricular fibrillation and sudden cardiac death.
The risk of torsades de pointes with sotalol is estimated at 1–4% and is dose-dependent, occurring more frequently at higher doses. Risk factors include:
- High doses of sotalol (particularly above 320 mg/day)
- Female sex (women have a higher baseline QT interval)
- Pre-existing QT prolongation
- Hypokalemia or hypomagnesemia
- Severe bradycardia
- Concomitant use of other QT-prolonging drugs
- Renal impairment (leading to drug accumulation)
- Congestive heart failure
According to the European Society of Cardiology (ESC) guidelines, initiation of sotalol therapy should ideally occur under continuous ECG monitoring for at least 3 days or until a steady state is reached, particularly in patients with additional risk factors for proarrhythmia.
How Should You Store Sotacor?
Keep Sotacor out of the sight and reach of children. Use before the expiry date stated on the packaging. Do not dispose of in wastewater or household waste.
Proper storage of Sotacor is important to maintain the medication's effectiveness and safety:
- Children: Keep out of the sight and reach of children
- Expiry date: Do not use Sotacor after the expiry date printed on the packaging. The expiry date refers to the last day of the stated month
- Storage conditions: No special storage conditions are required for this medicinal product
- Disposal: Do not throw away Sotacor via wastewater or with household waste. Return unused medication to your pharmacy for safe disposal, in accordance with local regulations, to help protect the environment
What Does Sotacor Contain?
Each Sotacor tablet contains 80 mg of sotalol hydrochloride as the active ingredient. The tablets also contain lactose monohydrate, microcrystalline cellulose, maize starch, colloidal anhydrous silica, stearic acid, and magnesium stearate as excipients.
Active ingredient
The active substance is sotalol hydrochloride 80 mg per tablet. Sotalol is a synthetic compound that exists as a racemic mixture of d-sotalol and l-sotalol. Both enantiomers contribute to the Class III antiarrhythmic (potassium channel blocking) effect, while the l-enantiomer is primarily responsible for the beta-blocking activity.
Excipients
Sotacor tablets also contain the following inactive ingredients:
- Lactose monohydrate — a sugar-based filler (patients with lactose intolerance should be aware)
- Microcrystalline cellulose — a plant-derived binder and filler
- Maize starch — a disintegrant that helps the tablet break down in the stomach
- Colloidal anhydrous silica — a flow agent used in tablet manufacturing
- Stearic acid — a lubricant
- Magnesium stearate — a lubricant used in tablet manufacturing
Appearance and packaging
Sotacor tablets are white, round, scored tablets. The score line allows the tablet to be divided into two equal halves for dose adjustment. They are available in the following pack sizes:
- 30 tablets — PVC/aluminium blister pack
- 100 tablets — PVC/aluminium blister pack or plastic container
Not all pack sizes may be marketed in every country.
Marketing Authorization Holder and Manufacturer
The marketing authorization holder for Sotacor is CHEPLAPHARM. The tablets are manufactured by FARMEA.
Frequently Asked Questions About Sotacor
Sotacor (sotalol) is used to treat and prevent cardiac arrhythmias (abnormal heart rhythms), including atrial fibrillation, atrial flutter, supraventricular tachycardia, and ventricular tachycardia. It works through a unique dual mechanism: as a beta-blocker (slowing heart rate and reducing blood pressure) and as a Class III antiarrhythmic (prolonging the heart's electrical refractory period to prevent re-entrant arrhythmia circuits). It is one of the few beta-blockers recommended for rhythm control in atrial fibrillation.
The most common side effects (affecting more than 1 in 10 patients) include shortness of breath, chest pain, diarrhea, palpitations, headache, fatigue and weakness, nausea and vomiting, slow heart rate (bradycardia), ECG abnormalities (QT prolongation), sleep disturbances, swelling (edema), and dizziness. Common side effects (up to 1 in 10) include depression, tingling sensations, heart failure, low blood pressure, rash, mood changes, abdominal pain, anxiety, sexual dysfunction, and muscle cramps. Most side effects are dose-dependent and may improve with dose reduction.
No, you should never stop taking Sotacor suddenly without medical supervision. Abrupt discontinuation can lead to serious rebound effects including worsening arrhythmias, rapid heart rate, and in patients with coronary artery disease, there is a risk of angina or even heart attack. Your doctor will create a tapering schedule, typically reducing the dose gradually over 1 to 2 weeks, to allow your body to adjust safely.
Sotacor should be taken on an empty stomach, at least 1 hour before meals. Food reduces the absorption of sotalol by approximately 20%, which can lead to inconsistent blood levels. Taking it at the same time each day, before meals, helps ensure reliable and predictable drug absorption and maintains stable therapeutic levels in the blood.
Sotacor should only be used during pregnancy when the potential benefit to the mother clearly justifies the risk to the fetus. Sotalol crosses the placenta and may cause bradycardia (slow heart rate), hypoglycemia (low blood sugar), and growth restriction in the developing baby. If treatment is necessary during pregnancy, the medication should ideally be stopped 48 to 72 hours before the expected delivery. The newborn should be monitored for 48 to 72 hours after birth for signs of beta-blockade. Breastfeeding is generally not recommended during sotalol treatment, as the drug passes into breast milk.
Sotacor (sotalol) is unique among beta-blockers because it has a dual mechanism of action. In addition to standard beta-blocking activity (Class II antiarrhythmic effect), which slows heart rate and reduces blood pressure, sotalol also blocks potassium channels in the heart (Class III antiarrhythmic effect), which prolongs the cardiac action potential and prevents re-entrant arrhythmias. This makes sotalol effective for both rate control and rhythm control of cardiac arrhythmias, whereas standard beta-blockers like metoprolol, atenolol, and bisoprolol are primarily effective for rate control only.
References and Sources
This article is based on the following evidence-based sources. All medical information has been reviewed according to international guidelines and the GRADE evidence framework.
- European Medicines Agency (EMA). Summary of Product Characteristics: Sotalol Hydrochloride. EMA/CHMP, latest revision. www.ema.europa.eu
- Hindricks G, Potpara T, Dagres N, et al. 2020 ESC Guidelines for the diagnosis and management of atrial fibrillation. European Heart Journal. 2021;42(5):373–498. doi:10.1093/eurheartj/ehaa612
- Brugada J, Katritsis DG, Arbelo E, et al. 2019 ESC Guidelines for the management of patients with supraventricular tachycardia. European Heart Journal. 2020;41(5):655–720. doi:10.1093/eurheartj/ehz467
- Al-Khatib SM, Stevenson WG, Ackerman MJ, et al. 2017 AHA/ACC/HRS guideline for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death. Circulation. 2018;138(13):e272–e391.
- Hohnloser SH, Woosley RL. Sotalol. New England Journal of Medicine. 1994;331(1):31–38. doi:10.1056/NEJM199407073310108
- British National Formulary (BNF). Sotalol Hydrochloride. NICE Evidence Services. bnf.nice.org.uk
- U.S. Food and Drug Administration (FDA). Sotalol Hydrochloride Label. FDA Drug Labeling. www.fda.gov
- Waldo AL, Camm AJ, deRuyter H, et al. Effect of d-sotalol on mortality in patients with left ventricular dysfunction after recent and remote myocardial infarction (SWORD trial). Lancet. 1996;348(9019):7–12. doi:10.1016/S0140-6736(96)02149-6
- UpToDate. Sotalol: Drug information and clinical uses. Wolters Kluwer, last updated 2025.
- Zipes DP, Camm AJ, Borggrefe M, et al. ACC/AHA/ESC 2006 guidelines for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death. European Heart Journal. 2006;27(17):2099–2140.
Medical Editorial Team
This article has been written and reviewed by the iMedic Medical Editorial Team, comprising licensed specialist physicians in cardiology and clinical pharmacology.
Medical Review Board
Board-certified cardiologists and clinical pharmacologists with expertise in antiarrhythmic drug therapy and beta-blocker pharmacology. All content follows ESC, AHA, and WHO guidelines.
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