Norbit
Disopyramide Capsule

Presentation
Norbit capsule: Each capsule contains Disopyramide Phosphate BP equivalent to Disopyramide 100 mg.

Description
Disopyramide Phosphate is a type 1 anti-arrhythmic drug. In animal studies Disopyramide decreases the rate of diastolic depolarization in cells with augmented automaticity, decreases the upstroke velocity and increases the action potential duration of normal cardiac cells, decreases the disparity of refractoriness between infracted and adjacent normally perfused myocardium and has no effect on alpha and beta adrenergic receptors. As a result it reduces heartbeat. After oral administration Disopyramide is absorbed rapidly and almost completely. About 50% of the given oral dose of Disopyramide is excreted through the urine as the unchanged drug.

Indications and Uses
Disopyramide is indicated for the ventricular arrhythmias, especially after myocardial infarction, supraventricular arrhythmias.

Dosage and Administration
The recommended dose of Norbit is 400 mg /day in 4 divided doses (100 mg capsule 6 hourly).
Patients with renal insufficiency should take 100 mg capsule according to the table below:

Creatinine clearance rate(ml/min)40-3030-15>15
Approximate dosing q 8 hrq 12 hrq 24 hr

Patients in whom rapid control of ventricular arrhythmia is essential, an initial loading dose of 300 mg Norbit is recommended, followed by the appropriate maintenance dosage.

Contraindications
Disopyramide is contraindicated in the pre-existing A-V heart block, shock, glaucoma, urinary retention and known hypersensitivity to the drug.

Precautions
Disopyramide should not be administered to patients with cardiomyopathy and associated congestive heart failure unless the patient is digitalized and adequately compensated. Disopyramide should be used with caution in the presence of digitalis intoxication.

Side-effects
Usually Disopyramide is well tolerated but occasionally in some cases dry mouth/nose/eye, nausea, vomiting, diarrhea, bloating, blurred vision, urinary problems, headache, skin rash, dizziness, nervousness & impotence (1-3%) may occur.

Use in pregnancy & lactation
Pregnancy: There are no adequate and well-controlled studies in pregnant women. Disopyramide should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Lactation: Because of the potential for serious adverse reactions in nursing infants from Disopyramide, 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.

Use in children
Safety and efficacy of disopyramide in infants less than one year have not been established.

Drug interactions
Drug-drug interactions may occur if Disopyramide is used along with beta-adrenoceptor blockers or verapamil HCl, lignocaine, phenytoin, procainamide or erythromycin.

Over dosage
Deliberate or accidental over dosage of oral Disopyramide may be followed by apnea, loss of consciousness & loss of spontaneous respiration. In such a case immediate hospitalization and all life saving measures should be taken.

Commercial Pack
Norbit capsule: Each box contains 3 blister strips of 10 capsules.