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Published on: April 5, 2011
Labetalol. Current research and therapeutic status
Archives of Internal Medicine
|March 1, 1983
Summary
Labetalol hydrochloride offers a dual mechanism for treating hypertension by blocking both alpha- and beta-adrenergic receptors. This new class of antihypertensive agents provides an expanded option for managing difficult hypertension cases.
Area of Science:
- Pharmacology
- Cardiovascular Medicine
- Drug Development
Background:
- Labetalol hydrochloride represents a novel class of antihypertensive agents.
- It acts by competitively and peripherally blocking both beta- and alpha-adrenergic receptors.
Purpose of the Study:
- To introduce labetalol hydrochloride as a new therapeutic option for hypertension.
- To detail its pharmacological profile and clinical applications.
Main Methods:
- Comparison of beta-blocking activity with propranolol hydrochloride.
- Comparison of alpha-blocking activity with phentolamine.
- Clinical use in oral and intravenous forms for various hypertension severities.
Main Results:
- Possesses approximately 25% of propranolol's beta-blocking activity and 50% of phentolamine's alpha-blocking activity.
- Effective beta- to alpha-blocking ratio in humans is approximately 7:1.
- Successfully used orally for mild to severe hypertension and intravenously for hypertensive emergencies.
Conclusions:
- Labetalol hydrochloride offers advantages over pure beta-blockers for certain hypertensive patients.
- It expands treatment options for physicians managing difficult hypertension.
- Key side effects include orthostatic hypotension and gastrointestinal disturbances.
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