Product Information
Registration Status: ActiveTEGRETOL CR 400 TABLET 400mg is approved to be sold in Singapore with effective from 1988-10-11. It is marketed by NOVARTIS (SINGAPORE) PTE LTD, with the registration number of SIN02388P.
This product contains Carbamazepine 400mg in the form of TABLET, FILM-COATED. It is approved for ORAL use.
This product is manufactured by NOVARTIS FARMA S P A in SWITZERLAND, andNOVARTIS PHARMA AG in ITALY.
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
An anticonvulsant used to control grand mal and psychomotor or focal seizures. Its mode of action is not fully understood, but some of its actions resemble those of phenytoin; although there is little chemical resemblance between the two compounds, their three-dimensional structure is similar. [PubChem]
Indication
For the treatment of epilepsy and pain associated with true trigeminal neuralgia.
Mechanism of Action
Carbamazepine inhibits sustained repetitive firing by blocking use-dependent sodium channels. Pain relief is believed to be associated with blockade of synaptic transmission in the trigeminal nucleus and seizure control with reduction of post-tetanic potentiation of synaptic transmission in the spinal cord. Carbamazepine also possesses anticholinergic, central antidiuretic, antiarrhythmic, muscle relaxant, antidepressant (possibly through blockade of norepinephrine release), sedative, and neuromuscular-blocking properties.
Pharmacokinetics
- Absorption
- In clinical studies, carbamazepine suspension, conventional tablets, and extended-release tablets delivered equivalent amounts of drug to the systemic circulation. However, it has been observed that the suspension is somewhat faster absorbed. Furthermore, the extended-release tablet is slightly slower than the conventional tablet. The bioavailability of the extended-release tablet is 89%, compared to the suspension. Plasma levels of carbamazepine are variable. The time to peak concentration for the different formulations are as follows: Suspension = 1.5 hours; Conventional tablets = 4-5 hours; Extended-release tablets = 3-12 hours.
- Distribution
- Metabolism
- Hepatic. CYP3A4 is the primary isoform responsible for the formation of carbamazepine-10,11-epoxide. This metabolite is active and shown to be equipotent to carbamazepine as an anticonvulsant. Carbamazepine is more rapidly metabolized to the aforementioned metabolite in younger patients than in adults. It also undergoes glucuronidation via UGT2B7, however this finding has been disputed.
- Elimination
Toxicity
Mild ingestions cause vomiting, drowsiness, ataxia, slurred speech, nystagmus, dystonic reactions, and hallucinations. Severe intoxications may produce coma, seizures, respiratory depression, and hypotension
Active Ingredient/Synonyms
5-Carbamoyl-5H-dibenz(b,f)azepine | 5-Carbamoyl-5H-dibenz[b,F]azepine | 5-Carbamoyl-5H-dibenzo(b,F)azepine | 5-Carbamyl-5H-dibenzo(b,F)azepine | 5H-Dibenz(b,F)azepine-5-carboxamide | Carbamazepen | Carbamazepin | Carbamazepina | Carbamazépine | Carbamazepinum | CBZ | Carbamazepine |
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.