Product Information
Registration Status: ActiveTRANTALOL TABLET 100mg is approved to be sold in Singapore with effective from 1990-10-24. It is marketed by DUOPHARMA (SINGAPORE) PTE LTD, with the registration number of SIN05162P.
This product contains Labetalol 100mg in the form of TABLET. It is approved for ORAL use.
This product is manufactured by DUOPHARMA (M) SDN BHD in MALAYSIA.
It is a Prescription Only Medicine that can only be obtained from a doctor or a dentist, or a pharmacist with a prescription from a Singapore-registered doctor or dentist.
Description
Blocker of both alpha- and beta-adrenergic receptors that is used as an antihypertensive. [PubChem]
Indication
For the management of hypertension (alone or in combination with other classes of antihypertensive agents), as well as chronic stable angina pectoris and sympathetic overactivity syndrome associated with severe tetanus. Labetalol is used parenterally for immediate reduction in blood pressure in severe hypertension or in hypertensive crises when considered an emergency, for the control of blood pressure in patients with pheochromocytoma and pregnant women with preeclampsia, and to produce controlled hypotension during anesthesia to reduce bleeding resulting from surgical procedures.
Mechanism of Action
Labetalol HCl combines both selective, competitive, alpha-1-adrenergic blocking and nonselective, competitive, beta-adrenergic blocking activity in a single substance. In man, the ratios of alpha- to beta- blockade have been estimated to be approximately 1:3 and 1:7 following oral and intravenous (IV) administration, respectively. The principal physiologic action of labetalol is to competitively block adrenergic stimulation of β-receptors within the myocardium (β1-receptors) and within bronchial and vascular smooth muscle (β2-receptors), and α1-receptors within vascular smooth muscle. This causes a decrease in systemic arterial blood pressure and systemic vascular resistance without a substantial reduction in resting heart rate, cardiac output, or stroke volume, apparently because of its combined α- and β-adrenergic blocking activity.
Pharmacokinetics
- Absorption
- Completely absorbed (100%) from the gastrointestinal tract with peak plasma levels occurring 1 to 2 hours after oral administration. The absolute bioavailability of labetalol is increased when administered with food.
- Distribution
- Metabolism
- Primarily hepatic, undergoes significant first pass metabolism
- Elimination
Toxicity
LD50 = 66 mg/kg (Rat, IV). Side effects or adverse reactions include dizziness when standing up, very low blood pressure, severely slow heartbeat, weakness, diminished sexual function, fatigue
Active Ingredient/Synonyms
3-Carboxamido-4-hydroxy-alpha-((1-methyl-3-phenylpropylamino)methyl)benzyl alcohol | 5-(1-Hydroxy-2-(1-methyl-3-phenylpropylamino)ethyl)salicylamide | Labetalol | Labetalolum | Labetolol | Labetalol |
Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.