Norpace
Norpace
[nor´pās]disopyramide
(dye-soe-peer-a-mide) disopyramide,Norpace
(trade name),Norpace CR
(trade name),Rythmodan
(trade name)Classification
Therapeutic: antiarrhythmicsIndications
Action
Therapeutic effects
Pharmacokinetics
Time/action profile (antiarrhythmic effects)
| ROUTE | ONSET | PEAK | DURATION |
| PO | 0.5–3.5 hr | 2.5 hr | 1.5–8.5 hr |
| PO-CR | 0.5–3.5 hr | 4.9 hr | 12 hr |
Contraindications/Precautions
Adverse Reactions/Side Effects
Central nervous system
- dizziness
- fatigue
- headache
Ear, Eye, Nose, Throat
- blurred vision
- dry eyes
- dry throat
Cardiovascular
- HF (life-threatening)
- arrhythmias
- AV block
- dyspnea
- edema
- hypotension
Gastrointestinal
- constipation (most frequent)
- dry mouth (most frequent)
- abdominal pain
- flatulence
- nausea
Genitourinary
- urinary hesitancy (most frequent)
- urinary retention (most frequent)
Endocrinologic
- hypoglycemia
Miscellaneous
- impaired temperature regulation
Interactions
Drug-Drug interaction
May potentiate anticoagulant effect of warfarin.Rifampin, phenobarbital, and phenytoin may ↓ blood levels and effectiveness.Cimetidine orerythromycin may ↓ metabolism and ↑ blood levels.May have additive toxic cardiac effects when used with other antiarrhythmics (prolonged conduction and ↓ cardiac output), especially verapamil —avoid using disopyramide for 48 hr before or 24 hr after.Anticholinergic side effects may be additive with other drugs having anticholinergic properties, including antihistamines and tricyclic antidepressants.↑ risk of arrhythmias with pimozide.↑ anticholinergic effects with angel's trumpet, jimson weed, and scopolia.Route/Dosage
Renal Impairment
Oral (Adults) CCr >40 mL/min or patients with hepatic impairment—100 mg q 6 hr; CCr 30–40 mL/min—100 mg q 8 hr; CCr 15–30 mL/min—100 mg q 12 hr; CCr <15 mL/min—100 mg q 24 hr as immediate-release dosage form.Availability (generic available)
Nursing implications
Nursing assessment
- Monitor BP, pulse, and ECG before and routinely throughout therapy. Check pulse before administering medication; withhold and notify health care professional if <60 or >120 bpm or if changes in rhythm.
- Monitor intake and output ratios and daily weight; assess for edema and urinary retention daily.
- Assess patient for signs of heart failure (peripheral edema, rales/crackles, dyspnea, weight gain, jugular venous distention). Notify health care professional if these occur.
- Lab Test Considerations: Renal and hepatic functions and serum potassium levels should be evaluated periodically throughout therapy.
- May cause elevated serum BUN, cholesterol, and triglyceride levels.
- May cause decreased blood glucose concentrations.
Potential Nursing Diagnoses
Decreased cardiac output (Indications)Impairedoral mucous membrane (Side Effects)
Implementation
- Do not confuse disopyramide with desipramine.
- When changing from quinidine sulfate to disopyramide, regular maintenance dose of disopyramide may be given 6–12 hr after last dose of quinidine sulfate.
- Extended-release form (CR formulations) is indicated for maintenance therapy only. When changing from regular form to extended-release forms, give the first dose of extended-release form 6 hr after the last regular dose.
- Oral: Administer medication on an empty stomach, 1 hr before or 2 hr after meals. CR form must be swallowed whole; do not break open, crush, or chew.
- Pharmacist may prepare a suspension with 100-mg capsules and cherry syrup.
Patient/Family Teaching
- Advise patient to take medication around the clock, as directed. Do not discontinue medication without consulting health care professional. If a dose is missed, take as soon as remembered unless within 4 hr of next dose. Do not double doses.
- Medication may cause dizziness. Caution patients to avoid driving or other activities requiring alertness until response to medication is known.
- Instruct patient to change positions slowly to minimize orthostatic hypotension.
- Advise patient that frequent mouth rinses, good oral hygiene, and sugarless gum or candy may help relieve dry mouth.
- Caution patient to avoid extremes of temperature, because this medication may cause impairment of body temperature regulation. Patient should use sunscreen and protective clothing to prevent photosensitivity reactions.
- Instruct patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and to consult health care professional before taking other Rx, OTC, herbal products, or alcohol.
- If constipation becomes a problem, advise patient that increasing bulk and fluids in the diet and exercising may minimize constipation.
- Instruct patient to notify health care professional if dry mouth, difficult urination, constipation, or blurred vision persists.
Evaluation/Desired Outcomes
- Suppression of PVCs and ventricular tachycardia.
- Prevention of further arrhythmias.