nadolol
Corgard

Available forms
Available by prescription only
Tablets: 20 mg, 40 mg, 80 mg, 120 mg, 160 mg

Indications and dosages
 Hypertension. Adults: Initially, 20 to 40 mg P.O. once daily. Dosage may be increased in 40- to 80-mg increments daily at 2- to 14-day intervals until optimum response occurs. Usual maintenance dosage is 40 or 80 mg once daily. Doses of up to 240 or 320 mg daily may be needed. Rarely, up to 640 mg daily.
 Long-term prophylactic management of chronic stable angina pectoris. Adults: Initially, 40 mg P.O. once daily. Dosage may be increased in 40- to 80-mg increments daily at 3- to 7-day intervals until optimum response occurs. Usual maintenance dosage is 40 or 80 mg once daily. Doses of up to 160 or 240 mg daily may be needed.
 Arrhythmias ◇. Adults: 60 to 160 mg P.O. daily.
 Prophylaxis of vascular headache ◇. Adults: 20 to 40 mg P.O. once daily; may gradually increase to 120 mg daily, if needed.
≡ Dosage adjustment. For renally impaired patients, see below.

Creatinine clearance (ml/min) Dosing interval 31-50 q 24-36 hr 10-30 q 24-48 hr < 10 q 40-60 hr

Pharmacodynamics
Antihypertensive action: Mechanism of antihypertensive effect is unknown. Drug may reduce blood pressure by blocking adrenergic receptors, thus decreasing cardiac output; by decreasing sympathetic outflow from the CNS; or by suppressing renin release.
Antianginal action: Nadolol decreases myocardial oxygen consumption, thus relieving angina, by blocking catecholamine-induced increases in heart rate, myocardial contraction, and blood pressure.

Pharmacokinetics
Absorption: 30% to 40% of a dose of nadolol is absorbed from the GI tract. Absorption isn’t affected by food.
Distribution: Distributed throughout the body; drug is about 30% protein-bound.
Metabolism: Not metabolized.
Excretion: Most of a given dose is excreted unchanged in urine; the remainder is excreted in feces. Plasma half-life is about 20 hours. Antihypertensive and antianginal effects persist for about 24 hours.

Contraindications and precautions
Contraindicated in patients hypersensitive to beta blockers, in those with bronchial asthma, sinus bradycardia, greater than first-degree heart block, overt cardiac failure, and cardiogenic shock. Use cautiously in patients with hyperthyroidism, heart failure, diabetes, chronic bronchitis, emphysema, impaired renal or hepatic function, and in CHF unless secondary to tachyarrhythmia that is treatable with beta blockers. Also use cautiously in those receiving general anesthesia before undergoing surgery.

Interactions
Drug-drug. Antiarrhythmics: May cause additive or antagonistic cardiac effects and additive toxic effects. Use together cautiously.
Antihypertensives, diuretics and, at high doses, the neuromuscular blocking effect of tubocurarine and related drugs: Potentiates antihypertensive effects. Monitor blood pressure.
Antimuscarinics, such as atropine: May antagonize nadolol-induced bradycardia. Use together cautiously.
Clonidine: Causes life-threatening and fatal increases in blood pressure after discontinuation of clonidine in patients receiving a beta blocker or after simultaneous withdrawal. Monitor blood pressure closely if drug therapy changes.
Insulin, oral hypoglycemics: Alters dosage requirements in stable diabetic patients. Monitor serum glucose level.
Sympathomimetics, such as epinephrine and isoproterenol: Antagonizes effects of these drugs. Use together cautiously.
Theophylline: May reduce theophylline elimination; may reduce effects of one or both drugs. Monitor patient for toxicity. A cardioselective beta blocker may be preferred.
Drug-lifestyle. Cocaine use: Inhibits therapeutic effects of nadolol. Inform patient of this interaction.

Adverse reactions
CNS: fatigue, dizziness, fever.
CV: bradycardia, hypotension,heart failure, peripheral vascular disease, rhythm and conduction disturbances.
GI: nausea, vomiting, diarrhea, abdominal pain, constipation, anorexia.
Respiratory: increased airway resistance.
Skin: rash.

Effects on lab test results
None reported.

Overdose and treatment
Evidence of overdose includes severe hypotension, bradycardia, heart failure, and bronchospasm.
 After acute ingestion, empty patient’s stomach by induced emesis or gastric lavage and give activated charcoal to reduce absorption. Magnesium sulfate may be given orally as a cathartic. Subsequent treatment is usually symptomatic and supportive. Drug is removable by hemodialysis.

Special considerations
• Dosage adjustments may be needed in patients with renal impairment.
• Nadolol has been used as an antiarrhythmic and as prophylaxis for migraine headaches.
• Monitor blood pressure closely at start of therapy and during dosage adjustments; once condition is stabilized, monitor patient at 3- to 6-month intervals.
• Monitor patient for reflex bradycardia, which may be treated with atropine.
• Monitor patients with hyperthyroidism and diabetes carefully; symptoms may be masked by drug therapy.
• If long-term therapy is used, gradually decrease dose over 1 to 2 weeks before discontinuing drug. Abrupt withdrawal can exacerbate angina and cause an MI.
Breast-feeding patients
• Drug appears in breast milk. An alternative to breast-feeding is recommended during therapy.
Pediatric patients
• Safety and efficacy in children haven’t been established; use only if potential benefit outweighs risk.
Geriatric patients
• These patients may need lower maintenance dosages of nadolol because of increased bioavailability or delayed metabolism; they also may experience enhanced adverse effects.

Patient education
• Tell patient that drug may be taken without regard for meals.
• Advise patient to obtain medical approval before taking OTC cold or allergy preparations.
• Inform diabetic patient that symptoms of hypoglycemia may be masked. Encourage frequent monitoring of blood glucose level.
• Tell patient not to stop nadolol abruptly. Drug should be tapered.

Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE THREATENING.
◆ Canada only
◇ Unlabeled clinical use