Norpace 100mg Capsules

Disopyramide is a Class IA antiarrhythmic agent that depresses the rate of diastolic depolarization (Phase 4) in ventricular muscle and Purkinje fibers, resulting in a decrease in the automaticity of ectopic pacemakers. It prolongs the effective refractory period (ERP) and action potential duration (APD) in the atria, ventricles, and accessory pathways. It also has significant anticholinergic (vagolytic) effects and a negative inotropic effect.

Urgent Side Effects: Seek Medical Help Right Away

Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you experience any of the following symptoms, contact your doctor or seek medical attention immediately:

Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of low blood sugar, including:
+ Dizziness
+ Headache
+ Feeling sleepy or weak
+ Shaking
+ Fast heartbeat
+ Confusion
+ Hunger
+ Sweating
New or worsening abnormal heartbeat
Chest pain or pressure
Changes in eyesight
Trouble passing urine, frequent urination, or urgent need to urinate
Muscle weakness
A type of abnormal heartbeat (prolonged QT interval) has been associated with this medication, which can lead to another type of unsafe abnormal heartbeat (torsades de pointes). If you experience a fast or abnormal heartbeat, or if you pass out, contact your doctor right away.
Heart failure has been reported with this medication, as well as worsening heart failure in people with pre-existing heart disease. If you have heart disease, inform your doctor. Seek medical attention immediately if you experience:
+ Shortness of breath
+ Sudden weight gain
+ Abnormal heartbeat
+ New or worsening swelling in the arms or legs

Other Possible Side Effects

Like all medications, this drug can cause side effects. Many people may not experience any side effects or may only have mild ones. If you are bothered by any of the following side effects or if they persist, contact your doctor or seek medical attention:

Headache
Constipation
Dry mouth, nose, or throat
Dry eyes
Dizziness, tiredness, or weakness
Bloating
Gas
Upset stomach
Stomach pain

This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.

Before taking this medication, it is essential to inform your doctor about the following:

Any allergies you have, including allergies to this drug, its components, or other substances, such as foods or medications. Be sure to describe the symptoms you experienced as a result of the allergy.
Certain health conditions, including:
+ Heart problems, such as heart block without a functioning pacemaker, heart failure, a prolonged QT interval on an electrocardiogram (ECG), or low blood pressure.
+ Eye conditions, specifically glaucoma.
+ Muscle disorders, such as myasthenia gravis.
+ Urinary difficulties, including trouble passing urine.
+ Kidney disease.
+ Abnormal potassium levels, either high or low.
+ Recent use of verapamil within the past 24 hours.

Please note that this is not an exhaustive list of all potential interactions. This medication can interact with numerous other drugs, which may increase the risk of severe, life-threatening, or fatal side effects. Therefore, it is crucial to inform your doctor and pharmacist about:

All prescription and over-the-counter medications you are taking.
Any natural products, vitamins, or supplements you are using.
* Your complete medical history, including all health problems.

Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to ensure your safety. It is your responsibility to verify that it is safe to take this medication in combination with all your other medications and health conditions.

It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. In some cases, your doctor may require you to start taking this drug in a hospital setting where you can be closely monitored. Be sure to discuss this with your doctor.

If you have diabetes (high blood sugar), it is crucial to closely monitor your blood sugar levels while taking this medication. Consult with your doctor for guidance.

Before consuming alcohol, talk to your doctor to discuss any potential risks or interactions.

If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects.

If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor. You and your doctor will need to discuss the potential benefits and risks of this medication to both you and your baby.

• Other Class IA antiarrhythmics (e.g., quinidine, procainamide)
• Drugs that significantly prolong QT interval (e.g., certain antipsychotics, macrolide antibiotics, fluoroquinolones, tricyclic antidepressants)
• Concomitant use with strong CYP3A4 inhibitors (e.g., ketoconazole, ritonavir) due to increased disopyramide levels and risk of QT prolongation.

• Beta-blockers (additive negative inotropic effects, bradycardia)
• Calcium channel blockers (e.g., verapamil, diltiazem - additive negative inotropic and dromotropic effects)
• Phenytoin, rifampin (CYP3A4 inducers - decreased disopyramide levels)
• Anticholinergic drugs (e.g., atropine, tricyclic antidepressants - additive anticholinergic effects)
• Diuretics (may cause hypokalemia, increasing risk of proarrhythmia)
• Digoxin (may increase digoxin levels, monitor)

• Amiodarone (may increase disopyramide levels, additive QT prolongation)
• Warfarin (potential for increased INR, monitor)
• Cimetidine (may increase disopyramide levels)
• Grapefruit juice (potential CYP3A4 inhibition, increased disopyramide levels)

• Antacids (may affect absorption, separate administration)

• Signs of heart failure exacerbation (e.g., dyspnea, edema, weight gain, fatigue)
• Proarrhythmic events (e.g., new or worsening palpitations, syncope, dizziness)
• Anticholinergic effects (e.g., dry mouth, blurred vision, urinary retention, constipation)
• Hypotension (dizziness, lightheadedness)
• Signs of hypersensitivity reaction (rare)

Use only if the potential benefit justifies the potential risk to the fetus. Disopyramide crosses the placenta. There are no adequate and well-controlled studies in pregnant women.

Disopyramide is excreted into breast milk. Due to the potential for serious adverse reactions in the nursing infant (e.g., arrhythmias, anticholinergic effects), a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Safety and efficacy have not been established in pediatric patients. Use is generally not recommended and should only be considered in life-threatening situations where other therapies are ineffective, with careful monitoring and expert consultation.

Elderly patients may be more sensitive to the effects of disopyramide, particularly the negative inotropic and anticholinergic effects, and may have reduced renal clearance. Lower initial doses and careful titration are recommended. Monitor closely for adverse effects and adjust dose based on renal function.

• Disopyramide has significant negative inotropic effects; use with extreme caution or avoid in patients with pre-existing heart failure or impaired left ventricular function.
• Its anticholinergic properties can be problematic, especially in elderly men with prostatic hypertrophy (risk of urinary retention) or patients with glaucoma (risk of acute angle-closure glaucoma).
• Hypokalemia and hypomagnesemia must be corrected prior to and during disopyramide therapy to minimize the risk of proarrhythmia, especially Torsades de Pointes.
• Therapeutic drug monitoring (TDM) of disopyramide plasma levels can be useful, especially in patients with renal/hepatic impairment, suspected toxicity, or inadequate response.
• Immediate-release capsules are typically dosed every 6 hours, while extended-release (CR) formulations are dosed every 12 hours. Ensure patients understand which formulation they are taking.
• Disopyramide is often considered a second-line agent for ventricular arrhythmias due to its side effect profile, but it can be effective in specific cases, particularly in hypertrophic cardiomyopathy to reduce outflow tract obstruction.

• Other Class I antiarrhythmics (e.g., procainamide, quinidine - though less commonly used due to similar or worse side effect profiles)
• Class III antiarrhythmics (e.g., amiodarone, sotalol, dofetilide)
• Beta-blockers (e.g., metoprolol, carvedilol)
• Calcium channel blockers (e.g., verapamil, diltiazem - for supraventricular arrhythmias)
• Catheter ablation
• Implantable Cardioverter-Defibrillator (ICD) for high-risk ventricular arrhythmias

If your symptoms or health condition do not improve or worsen over time, it is essential to contact your doctor for further evaluation and guidance. To ensure your safety and the effectiveness of your treatment, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it is a good idea to consult with your pharmacist to see if this applies to your prescription. If you have any questions or concerns about your medication, do not hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider for clarification and guidance. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide detailed information about the overdose, including the name of the medication taken, the amount, and the time it occurred.