moricizine hydrochloride

moricizine hydrochloride

Ethmozine

Pharmacologic class: Sodium channel blocker

Therapeutic class: Antiarrhythmic (class IA)

Pregnancy risk category B

FDA Boxed Warning

• Drug has known proarrhythmic properties and doesn't improve survival in patients without life-threatening arrhythmias. Use only for patients with life-threatening ventricular arrhythmias.

Action

Prolongs PR interval and QRS duration by blocking sodium influx across myocardial cell membrane, thereby decreasing myocardial irritability and preventing arrhythmias

Availability

Tablets: 200 mg, 250 mg, 300 mg

⊘Indications and dosages

➣ Life-threatening ventricular arrhythmias, including sustained ventricular tachycardia

Adults: 600 to 900 mg/day P.O. q 8 hours in divided doses. Adjust by 150 mg/day q 3 days as needed and tolerated.

Dosage adjustment

• Hepatic or renal impairment

Contraindications

• Hypersensitivity to drug
• Cardiogenic shock
• Heart block

Precautions

Use cautiously in:
• severe renal or hepatic impairment, heart failure, coronary artery disease, sick sinus syndrome, electrolyte disturbances
• pregnant or breastfeeding patients
• children (safety not established).

Administration

• Administer with meals.
• Know that some patients tolerate dosing every 12 hours. Assess closely for increased dizziness and nausea.

Route	Onset	Peak	Duration
P.O.	1 hr	0.5-2 hr	10-24 hr

Adverse reactions

CNS: dizziness, fatigue, headache, nervousness, weakness, paresthesia, sleep disorders, cerebrovascular events

CV: chest pain, palpitations, hypotension, hypertension, thrombophlebitis, arrhythmias, heart failure

EENT: blurred vision

GI: nausea, vomiting, diarrhea, dyspepsia, dry mouth

Musculoskeletal: pain

Respiratory: dyspnea

Skin: sweating

Other: drug fever

Interactions

Drug-drug. Cimetidine: increased moricizine blood level

Digoxin: prolonged PR interval

Theophylline: decreased theophylline blood level

Patient monitoring

• Assess baseline ECG; monitor periodically during therapy.
• Monitor vital signs. Watch for drug-induced fever, hypotension, and rebound hypertension.
• Monitor patient's weight and fluid intake and output.
• Assess cardiovascular and neurologic status carefully.

Patient teaching

• Instruct patient to take with meals to minimize GI upset.
• Advise patient to take exactly as prescribed and not to double the dose. Tell him he may take missed dose up to 6 hours after previous dose.
☞ Caution patient not to stop taking drug suddenly. Dosage must be tapered gradually.
☞ Teach patient to recognize and immediately report signs and symptoms of heart failure, irregular heart beats, and cerebrovascular events.
• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs mentioned above.