Labetalol Pharmacology

Labetalol

About Labetalol
A mixed alpha/beta Adrenergic antagonist, Antihypertensive(pregnancy-induced hypertension).
Mechanism of Action of Labetalol
Labetalol is an adrenergic antagonist capable of blocking alpha-1, beta-1, and beta-2 receptors and additional weak beta-2 agonistic action. It decreases heart rate, myocardial contraction, cardiac output, total peripheral resistance and B.P. Fall in B.P. is due to alpha-1 and beta-1 blockade as well as beta-2 agonism (vasodilatation). It also inhibits nor adrenaline uptake by adrenergic nerve endings.
Pharmacokinets of Labetalol
Absorption: Well absorbed orally, but low bioavailability due to first pass metabolism.
Distribution: Widely distributed.
Excretion: Excreted through urine and faeces.
Onset of Action for Labetalol
2 to 4 hours
Duration of Action for Labetalol
Up to 12 hours
Half Life of Labetalol
6 to 8 hours
Side Effects of Labetalol
1. Gastrointestinal disturbances
2. Diarrhoea
3. Dry mouth
4. Cholestasis
5. Fluid retention
6. Nervousness
7. Sexual dysfunction
8. Muscle cramps
9. Depression
10. Dyspnoea
11. Drowsiness
12. Headache
13. Paraesthesia
14. Visual impairment
15. Rash
16. Alopecia
17. Urinary retention
18. Long term therapy produces antinuclear antibodies

Contra-indications of Labetalol
1. Uncontrolled heart failure
2. Second or third degree heart block
3. Cardiogenic shock
4. Severe Bradycardia
5. Bronchospasm
6. Hypersensitivity to the drug
7. Along with anaesthetic drugs producing myocardial depression

Special Precautions while taking Labetalol
1.Cardiac failure
2.Peripheral vascular diseases
3.Hepatic impairment
4. The drug should be gradually withdraw with caution
5. Use with caution in chronic obstructive pulmonary diseases
6. Diabetes mellitus
7. Hyperthyroidism
8. Postural hypotension
Pregnancy Related Information
Use with caution
Old Age Related Information
Use with caution
Breast Feeding Related Information
Use with caution
Children Related Information
Contraindicated
Indications for Labetalol
1. Phaeochromocytoma
2. Hypertensive emergencies
3. Clonidine withdrawal
4. All grades of hypertension
5. Cheese reaction
6. Late onset pregnancy hypertension

Interactions for Labetalol
Tricyclic antidepressants: Increased incidence of tremor.
Cimetidine: Bioavailability of labetalol is enhanced.
Beta-adrenergic agonists: Can decrease the bronchodilator effects of these drugs in patients with bronchospasm.
Halothane: Significant myocardial depression with I.V. labetalol. Don`t use high concentration (3% or above) of halothane.
Nitroglycerin: Labetalol blunts reflex tachycardia produced by nitroglycerin without preventing its hypotensive effect.
Lab.tests: False increase in urinary catecholamine levels by nonspecific trihydroxy-indole reaction. Reversible increase in serum transaminases.
Rarely reversible increase in blood urea.
Typical Dosage for Labetalol
Phaeochromocytoma & Hypertension: 100mg orally 12th hourly. Increases the dosage by 100mg up to 600mg 12th hourly at every 2-3 days intervals depending up on patient`s response
Maximum dose: 2400mg
Hypertensive emergencies, Severe hypertension, & Clonidine withdrawal :
Starts with 20mg I.V. bolus over 2minutes. Increases the dosage at every 10minutes intervals by 40 to 80mg up to 300mg based on patient`s response.
Schedule of Labetalol
H
Storage Requirements for Labetalol
Store in a dry place below 30 degree C. and protect from light, moisture, and freezing. Keep out of reach of children.
Effects of Missed Dosage of Labetalol
Take the missed dose as soon as remember and If it is the time for next dose then skip the missed dose and take the regular dose.
Effects of Overdose of Labetalol
Treatment is supportive and symptomatic. After ingestion empty the stomach by induced emesis or gastric lavage. Administer activated charcoal to reduce absorption. . Treat Bradycardia with atropine. If required administer isoproterinol with caution; in heart block. Treat hypotension with glucagons and vasopressors like epinephrine. Treat cardiac failure with diuretics and cardiac glycosides.

Home Delivery for Labetalol in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including labetalol.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for labetalol and other medicines and health products. Home delivery services for labetalol may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take labetalol only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for labetalol before they complete the sale. You can get this information while placing the order for labetalol with the pharmacy.

Labetalol is a generic medicine name and there are several brands available for it. Some of the brands for labetalol might be better known than labetalol itself. If the pharmacy that's willing to deliver medicines to your home doesn't have labetalol in stock, you can ask for one of the branded alternatives for labetalol.