indication

For the management of hypertension and ventricular premature beats in adults.

pharmacology

Acebutolol is a cardioselective, beta-adrenoreceptor blocking agent, which possesses mild intrinsic sympathomimetic activity (ISA) in its therapeutically effective dose range. In general, beta-blockers reduce the work the heart has to do and allow it to beat more regularly. Acebutolol has less antagonistic effects on peripheral vascular ß2-receptors at rest and after epinephrine stimulation than nonselective beta-antagonists. Low doses of acebutolol produce less evidence of bronchoconstriction than nonselective agents like propranolol but more than atenolol.

mechanism of action

Acebutolol is a selective β1-receptor antagonist. Activation of β1-receptors by epinephrine increases the heart rate and the blood pressure, and the heart consumes more oxygen. Acebutolol blocks these receptors, lowering the heart rate and blood pressure. This drug then has the reverse effect of epinephrine. In addition, beta blockers prevent the release of renin, which is a hormone produced by the kidneys which leads to constriction of blood vessels.

toxicity

Symptoms of overdose include extreme bradycardia, advanced atrioventricular block, intraventricular conduction defects, hypotension, severe congestive heart failure, seizures, and in susceptible patients, bronchospasm, and hypoglycemia.

biotransformation

Subject to extensive first-pass hepatic biotransformation (primarily to diacetolol).

absorption

Well absorbed from the Gl tract with an absolute bioavailability of approximately 40% for the parent compound. In

half life

The plasma elimination half-life is approximately 3 to 4 hours. The half-life of its metabolite, diacetolol, is 8 to 13 hours.

route of elimination

Elimination via renal excretion is approximately 30% to 40% and by non-renal mechanisms 50% to 60%, which includes excretion into the bile and direct passage through the intestinal wall.

drug interactions

Acetohexamide: Acebutolol may decrease symptoms of hypoglycemia and increase the time required for the body to compensate for hypoglycemia.

Chlorpropamide: Acebutolol may decrease symptoms of hypoglycemia and increase the time required for the body to compensate for hypoglycemia.

Clonidine: Increased hypertension when clonidine stopped

Dihydroergotamine: Ischemia with risk of gangrene

Dihydroergotoxine: Ischemia with risk of gangrene

Disopyramide: Acebutolol may decrease symptoms of hypoglycemia and increase the time required for the body to compensate for hypoglycemia.

Epinephrine: Hypertension, then bradycardia

Ergonovine: Ischemia with risk of gangrene

Ergotamine: Ischemia with risk of gangrene

Fenoterol: Antagonism

Formoterol: Antagonism

Gliclazide: Acebutolol may decrease symptoms of hypoglycemia and increase the time required for the body to compensate for hypoglycemia.

Glipizide: Acebutolol may decrease symptoms of hypoglycemia and increase the time required for the body to compensate for hypoglycemia.

Glisoxepide: The beta-blocker, acebutolol, may decrease symptoms of hypoglycemia.

Glyburide: Acebutolol may decrease symptoms of hypoglycemia and increase the time required for the body to compensate for hypoglycemia.

Ibuprofen: Risk of inhibition of renal prostaglandins

Indomethacin: Risk of inhibition of renal prostaglandins

Insulin Aspart: The beta-blocker, acebutolol, may decrease symptoms of hypoglycemia.

Insulin Detemir: The beta-blocker, acebutolol, may decrease symptoms of hypoglycemia.

Insulin Glargine: The beta-blocker, acebutolol, may decrease symptoms of hypoglycemia.

Insulin Glulisine: The beta-blocker, acebutolol, may decrease symptoms of hypoglycemia.

Insulin Lispro: The beta-blocker, acebutolol, may decrease symptoms of hypoglycemia.

Isoproterenol: Antagonism

Lidocaine: The beta-blocker, acebutolol, may increase the effect and toxicity of lidocaine.

Methysergide: Ischemia with risk of gangrene

Orciprenaline: Antagonism

Pipobroman: Antagonism

Pirbuterol: Antagonism

Piroxicam: Risk of inhibition of renal prostaglandins

Prazosin: Risk of hypotension at the beginning of therapy

Repaglinide: Acebutolol may decrease symptoms of hypoglycemia and increase the time required for the body to compensate for hypoglycemia.

Salmeterol: Antagonism

Terazosin: Increased risk of hypotension. Initiate concomitant therapy cautiously.

Terbutaline: Antagonism

Tolazamide: Acebutolol may decrease symptoms of hypoglycemia and increase the time required for the body to compensate for hypoglycemia.

Tolbutamide: Acebutolol may decrease symptoms of hypoglycemia and increase the time required for the body to compensate for hypoglycemia.

Treprostinil: Additive hypotensive effect. Monitor antihypertensive therapy during concomitant use.

Verapamil: Increased effect of both drugs