Acebutolol is a cardioselective, β-adrenoreceptor blocking agent, which possesses mild intrinsic sympathomimetic activity (ISA) in its therapeutically effective dose range.

Hypertension

Acebutolol hydrochloride capsules, USP are indicated for the management of hypertension in adults. It may be used alone or in combination with other antihypertensive agents, especially thiazide-type diuretics.

Ventricular Arrhythmias

Acebutolol hydrochloride capsules, USP are indicated in the management of ventricular premature beats; it reduces the total number of premature beats, as well as the number of paired and multiform ventricular ectopic beats, and R-on-T beats.

Hypertension

The initial dosage of acebutolol in uncomplicated mild-to-moderate hypertension is 400 mg. This can be given as a single daily dose, but in occasional patients twice daily dosing may be required for adequate 24-hour blood-pressure control. An optimal response is usually achieved with dosages of 400 to 800 mg per day, although some patients have been maintained on as little as 200 mg per day. Patients with more severe hypertension or who have demonstrated inadequate control may respond to a total of 1200 mg daily (administered b.i.d.), or to the addition of a second antihypertensive agent. Beta-1 selectivity diminishes as dosage is increased.

Ventricular Arrhythmia

The usual initial dose of acebutolol is 400 mg daily given as 200 mg b.i.d. Dosage should be increased gradually until an optimal clinical response is obtained, generally at 600 to 1200 mg per day. If treatment is to be discontinued, the dosage should be reduced gradually over a period of about two weeks.

Acebutolol is well tolerated in properly selected patients. Most adverse reactions have been mild, not required discontinuation of therapy, and tended to decrease as duration of treatment increases.

The following selected (potentially important) side effects were seen in up to 2% of acebutolol patients:

Cardiovascular: hypotension, bradycardia, heart failure.

Central Nervous System: anxiety, hyper/hypoesthesia, impotence.

Dermatological: pruritus.

Gastrointestinal: vomiting, abdominal pain.

Genitourinary: dysuria, nocturia.

Liver and Biliary System: A small number of cases of liver abnormalities (increased SGOT, SGPT, LDH) have been reported in association with acebutolol therapy. In some cases increased bilirubin or alkaline phosphatase, fever, malaise, dark urine, anorexia, nausea, headache, and/or other symptoms have been reported. In some of the reported cases, the symptoms and signs were confirmed by rechallenge with acebutolol. The abnormalities were reversible upon cessation of acebutolol therapy.

Musculoskeletal: back pain, joint pain.

Respiratory: pharyngitis, wheezing.

Special Senses: conjunctivitis, dry eye, eye pain.

Autoimmune: In extremely rare instances, systemic lupus erythematosus has been reported.

Acebutolol HCl, USP is contraindicated in: 1) persistently severe bradycardia; 2) second- and third-degree heart block; 3) overt cardiac failure; and 4) cardiogenic shock

Cardiac Failure

Sympathetic stimulation may be essential for support of the circulation in individuals with diminished myocardial contractility, and its inhibition by β-adrenergic receptor blockade may precipitate more severe failure. Although β-blockers should be avoided in overt cardiac failure, acebutolol can be used with caution in patients with a history of heart failure who are controlled with digitalis and/or diuretics. Both digitalis and acebutolol impair AV conduction. If cardiac failure persists, therapy with acebutolol should be withdrawn.

Risk of Anaphylactic Reaction

Impaired Renal of Hepatic Function

Patients, especially those with evidence of coronary artery disease, should be warned against interruption or discontinuation of acebutolol therapy without a physician’s supervision.