Labetalol HCl

labetalol-beta blocker

1. Labetalol HCL Ala’a Fadhel Hassan Al Mahmoudia G. Hospital

2. Mechanism of action Competitively blocks β-receptors within the myocardium (β 1 ) and within bronchial and vascular smooth muscle (β 2 ) and α 1 -receptors within vascular smooth muscle Has some intrinsic β 2 -agonist activity   Produces a dose-dependent (at usual doses) decrease in systemic arterial BP and systemic vascular resistance without a substantial reduction in resting heart rate, cardiac output, or stroke volume Generally has little effect on sinus rate, intraventricular- conduction, the His-Purkinje system, or duration of the QRS complex

3. Indication Hypertension Severe Hypertension and Hypertensive Crisis Preeclampsia Controlled Hypotension during Anesthesia Angina Tetanus Unlabeled Uses( pheochromocytoma & clonidine -withdrawal hypertension)

4. Pharmacokinetics Rapidly absorbed from GIT following oral adm.(90-100%) still food both delay & increase absorption of drug Absolute bioavailability ~25% (increase with geriatric pt & pt. with hepatic impairment) It undergoes extensive liver metabolism & elimination via biliary route (30%) & (55%) as glucuronide conjugates T 50% average 2.5-8 hr., duration is dose dependent (orally 8-24hr & I.V 2-4 hr)

5. Adverse effect Mentioned adverse effects associated with CNS CVS GIT & hepatic Genitourinary tract Respiratory tract Dermatologic EENT

6. Contraindications Bronchial asthma; overt cardiac failure; greater than first-degree heart block; cardiogenic shock; severe bradycardia; conditions associated with severe and prolonged hypotension; history of obstructive airway disease, including asthma; hypersensitivity to any component of the product.