ACEBUTOLOL HYDROCHLORIDE
Clinical safety rating: caution
Comprehensive clinical and safety monograph for ACEBUTOLOL HYDROCHLORIDE (ACEBUTOLOL HYDROCHLORIDE).
Selective beta-1 adrenergic receptor antagonist (cardioselective beta-blocker) with intrinsic sympathomimetic activity (ISA). Competitively blocks catecholamine binding at cardiac beta-1 receptors, reducing heart rate, myocardial contractility, and blood pressure. ISA provides mild beta-receptor stimulation, decreasing the extent of resting bradycardia and lipid changes.
| Metabolism | Extensively metabolized in the liver via first-pass effect to an active metabolite, diacetolol. CYP2D6 is involved in metabolism. Diacetolol is primarily excreted renally. |
| Excretion | Renal: 30-40% as unchanged drug and 50-60% as diacetolol; fecal: ~10% |
| Half-life | 3-4 hours for acebutolol; 8-13 hours for diacetolol (active metabolite); clinically significant in renal impairment |
| Protein binding | 11-24% bound to albumin |
| Volume of Distribution | 1.2 L/kg; indicates moderate tissue distribution |
| Bioavailability | Oral: 35-45% (first-pass effect reduces absorption) |
| Onset of Action | Oral: 1-1.5 hours; IV: within minutes |
| Duration of Action | Oral: 12-24 hours (beta-blockade peaks at 2-4 hours); IV: 2-4 hours |
Dose: 200-800 mg/day orally in 1-2 divided doses. Initially 200 mg twice daily; may increase to 400 mg twice daily as needed.
| Dosage form | CAPSULE |
| Renal impairment | CrCl 25-49 ml/min: reduce dose by 50%; CrCl <25 ml/min: reduce dose by 75%. Avoid if on dialysis. |
| Liver impairment | Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50% or extend dosing interval; Child-Pugh C: avoid use due to significant metabolism. |
| Pediatric use | Not established; limited data: initial 1-2 mg/kg/day divided twice daily; titrate up to 4-6 mg/kg/day; do not exceed 200 mg/day. |
| Geriatric use | Start at 200 mg daily; increase cautiously; monitor heart rate, blood pressure, and renal function; may require lower maintenance doses due to age-related decline in renal function. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for ACEBUTOLOL HYDROCHLORIDE (ACEBUTOLOL HYDROCHLORIDE).
| Breastfeeding | Acebutolol and its active metabolite diacetolol are excreted into breast milk with a milk-to-plasma ratio of approximately 2.5 for acebutolol and 7.1 for diacetolol. Use with caution due to potential for infant beta-blockade effects; monitor infant for bradycardia and hypotension. |
| Teratogenic Risk | First trimester: Available data are limited but do not suggest a major increase in congenital anomalies. Second and third trimesters: Exposure may cause fetal bradycardia, intrauterine growth restriction, and hypoglycemia. Avoid use near term due to risk of neonatal bradycardia, hypotension, and respiratory depression. |
■ FDA Black Box Warning
Abrupt cessation of therapy may exacerbate angina pectoris and precipitate myocardial infarction or ventricular arrhythmias. Taper dose gradually over 1-2 weeks.
| Serious Effects |
["Sinus bradycardia","Heart block greater than first degree","Cardiogenic shock","Overt cardiac failure","Hypersensitivity to acebutolol or other beta-blockers"]
| Precautions | ["Exacerbation of ischemic heart disease following abrupt withdrawal","May mask signs of hypoglycemia in diabetic patients","May mask signs of thyrotoxicosis","Use caution in patients with peripheral vascular disease","May worsen heart failure; use cautiously in compensated failure","Bronchospasm risk in patients with COPD/asthma (relative selectivity lost at higher doses)","May cause or exacerbate psoriasis","Use in pregnancy only if potential benefit justifies risk","Dose adjustment in renal impairment"] |
| Food/Dietary | Avoid alcohol, which can increase hypotension and dizziness. No specific food interactions; take with or without food. |
Loading safety data…
| Fetal Monitoring | Monitor maternal heart rate, blood pressure, and fetal heart rate during pregnancy. Assess fetal growth with ultrasound due to potential for intrauterine growth restriction. Monitor neonates for bradycardia, hypoglycemia, and respiratory depression after delivery. |
| Fertility Effects | No specific studies on human fertility; beta-blockers in general may impair male erectile function and libido. Animal studies show no significant adverse effects on fertility. |
| Clinical Pearls | Acebutolol is a cardioselective beta-blocker with intrinsic sympathomimetic activity (ISA), which may reduce bradycardia and bronchospasm risk compared to non-selective agents. Monitor for masking of hypoglycemia in diabetic patients. Use with caution in peripheral vascular disease. Can cause lupus-like syndrome; monitor for antinuclear antibodies (ANA) if symptoms develop. Avoid abrupt discontinuation to prevent rebound hypertension. |
| Patient Advice | Take at the same time each day to maintain consistent blood levels. · Do not stop taking suddenly, as this can cause chest pain or heart attack. · May cause dizziness or fatigue; avoid driving until you know how it affects you. · Report any unexplained rash, joint pain, or fever to your doctor. · Monitor heart rate and blood pressure regularly as directed. · Inform all healthcare providers you are taking this medication before surgery. |