Indications 

Norpace CR is an oral medicine used to treat certain types of serious irregular heartbeat, such as sustained ventricular tachycardia. It can be indicated for the treatment of documented ventricular arrhythmias that have not responded to other antiarrhythmic agents. 

Norpace contains the active ingredient called disopyramide phosphate, which is an antiarrhythmic drug. It works by blocking certain electrical signals in the heart. Treating an irregular heartbeat can decrease the risk for blood clots, and this effect can reduce your risk of heart attack or stroke. 

Use and Dosage 

Norpace is available in the form of CR capsules to take it by mouth with or without food exactly as prescribed by your doctor, usually 4 times daily. The capsules should be swallowed whole without crushing or chewing.  

The dosage will depend on your age, medical condition, and response to treatment. However, the usual adult dosage of Norpace CR is 200 to 400 mg per day given in divided doses. Take the capsules at the same time(s) every day to maintain a consistent level of the medication in your bloodstream. Do not stop taking it without consulting with your healthcare provider, as suddenly stopping the medication can cause serious problems. 

If you miss a dose of Norpace CR, take it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. 

Side Effects 

Common Side Effects 

• Aches or pains 
• Blurred vision  
• Constipation 
• Dizziness  
• Dry mouth 
• Dry nose, dry eyes, or dry throat  
• Fatigue or muscle weakness  
• Feeling unwell  
• Frequent or urgent urination  
• Headache  
• Nausea  
• Pain, bloating, or gas  
• Trouble starting to urinate or maintaining urine flow 
• Trouble urinating 

Serious Side Effects 

• Blurred vision 
• Confusion 
• Difficulty breathing 
• Eye pain or swelling 
• Fast heart rate 
• Hives 
• Hunger 
• Irritability 
• Jitteriness 
• Lightheadedness 
• Little or no urinating 
• New or worsening irregular heartbeat pattern 
• Painful or difficult urination 
• Rapid weight gain 
• Seeing halos around lights 
• Shortness of breath 
• Sudden vision loss 
• Sweating 
• Swelling of your face lips tongue or throat 
• Tunnel vision 
• Weakness 

Cautions 

• Norpace CR should not be used in patients with certain heart conditions, such as complete heart block and cardiogenic shock. 
• Disopyramide can cause serious arrhythmias, which may increase the risk of sudden cardiac death. Therefore, it should be used with caution in patients with a history of arrhythmias or other heart conditions. 
• Disopyramide can cause anticholinergic side effects, such as dry mouth, constipation, and urinary retention. Therefore, it should be used with caution in patients with a history of urinary retention, glaucoma, or other conditions that may be exacerbated by anticholinergic drugs. 
• Disopyramide can interact with other medications, such as beta-blockers, calcium channel blockers, and anticholinergic drugs. Therefore, inform your healthcare provider of all the medications you are taking before starting the capsules. 
• Norpace CR can cause dizziness, blurred vision, and other side effects that may impair your ability to drive or operate machinery. Therefore, you should avoid these activities until you know how Norpace CR affects you. 
• Disopyramide can cause QT prolongation, a condition in which the heart takes longer than normal to recharge between beats. This can lead to a potentially life-threatening arrhythmia called torsades de pointes. Therefore, Norpace CR should be used with caution in patients with a history of QT prolongation or other risk factors for torsades de pointes, such as electrolyte imbalances and certain medications. 
• Norpace CR can cause a variety of gastrointestinal side effects, such as nausea, vomiting, and diarrhea. Therefore, it should be used with caution in patients with a history of gastrointestinal disorders. 
• Disopyramide can cause allergic reactions in some patients, including rash, itching, and swelling. Therefore, if you experience any of these symptoms while taking the capsules, you should contact your healthcare provider immediately.