CARBAMAZEPINE (Tegretol): What is used for?

What is Carbamazepine?

Carbamazepine is an active ingredient used for the treatment of epileptic seizures, neuralgia, alcohol withdrawal syndrome and prophylaxis of manic-depressive illness.

The brand names of Carbamazepine in the United States are: Carbamazepine, Carbamazepine, Carbamazepine, Carbamazepine, Carbamazepine, Carbamazepine, Carbamazepine: Tegretol, Epitol, Tegretol XR and Carbatrol.

Carbamazepine Mechanism of Action (MOA)

It reduces glutamate release, stabilizes neuronal membranes and depresses dopamine and noradrenaline exchange.

Therapeutic Indications and Dosage of Carbamazepine

– Partial epileptic seizures with complex or simple symptomatology with or without secondary generalization; generalized tonic-clonic epileptic seizures; epilepsies with mixed epileptic seizures.
Monitor plasma levels for optimal dosage.

Oral, adults: initial 100-200 mg 1 or 2 times/day; slowly increase to 400 mg 2 or 3 times/day.
Oral, children: < 4 years, initial 20-60 mg/day increasing by 20-60 mg every 2 days; > 4 years, initial 100 mg/day increasing by 100 mg at weekly intervals; maintenance 10-20 mg/kg/day in divided doses.

– Essential glossopharyngeal neuralgia. Essential trigeminal neuralgia: oral, initial 200-400 mg/day (elderly, 100 mg 2 times/day); increase slowly until pain is suppressed (200 mg 3-4 times/day); then gradually reduce to minimum maintenance dose.

– Alcohol withdrawal syndrome: oral, 200 mg 3 times/day. Initially combine with sedative-hypnotics and, remitted acute stage, continue in monotherapy.

– Mania and prophylaxis of manic-depressive disease: oral, range 400-1,600 mg/day; usually 400-600 mg/day in 2-3 doses.

Method of administration of Carbamazepine

Eat during, after or between meals with a little liquid.

Contraindications to Carbamazepine

• Hypersensitivity to carbamazepine and structurally related drugs (e.g., tricyclic antidepressants).
• Atrioventricular block, history of bone marrow depression or hepatic porphyrias (e.g. intermittent acute porphyria, variegate, late skin).
• Treatment with MAOI or 2 weeks later.

Warnings and Precautions with Carbamazepine

• Elders.
• Aplastic anemia, agranulocytosis, thrombocytopenia or leukopenia may appear.
• Suspend treatment for bone marrow depression, severe skin reactions, aggravation of liver dysfunction, active liver disease, exacerbation of epileptic seizures.
• Causes failure of oral contraceptives.
• Monitor levels in case of increased crisis, pregnancy, children, adolescents, absorption disorders.
• Gradually suspend treatment.
• Cross sensitivity with oxcarbazepine and phenytoin.
• Caution in mixed crises that include absences and in high IOP. Activates latent psychosis.
• Assess risk/benefit in antecedents of cardiac, hepatic, renal disease, hematological reactions to other drugs or interrupted periods of treatment.
• Control hemogram, hepatic function and urine analysis.
• May cause multiorgan hypersensitivity reactions. Control signs of suicidal ideas and behaviors.

Liver failure

Caution.
Assess risk/benefit in patients with a history of liver disease.
Suspend treatment for aggravation of liver dysfunction or active liver disease.

Kidney failure

Caution.
Assess risk/benefit in patients with a history of kidney disease.

Interactions with Carbamazepine

• Plasma levels and toxicity increased (adjust dose) by: CYP3A4 inhibitors, isoniazid, macrolides, azoles, protease inhibitors, verapamil, diltiazem, dextropropoxyphene, ibuprofen, viloxazine, fluoxetine, fluvoxamine, nefazodone, paroxetine, trazodone, styripentol, vigabatrin, terfenadine, loratadine, loxapine, olanzapine, quetiapine, nicotinamide, acetazolamide, danazol, oxybutynin, dantrolene, ticlopidine, grapefruit juice, progabide, valnoctamide, ac. valproic, valpromide and primidone.
• Plasma levels decreased by: inducers CYP3A4, phenobarbital, phenytoin, phosphophenytoin, primidone, metosuximide, fensuximide, oxcarbazepine, theophylline, aminophylline, rifampicin, cisplatin, doxorubicin, H. perforatum, buprenorphine, mianserin, sertraline.
  Altered lightening (monitor) by: isotretinoin.
• Decreases levels and effect of: clozapine, haloperidol, bromperidol, olanzapine, quetiapine, risperidone, ziprasidone, lamotrigine, tiagabine, topiramate, clonazepam, etosuximide, primidone, ac. valproic, felbamate, zonisamide, oxcarbazepine, clobazam, alprazolam, corticosteroids, doxycycline, itraconazole, protease inhibitors, oral contraceptives, estrogens, progestagens, bupropion, citalopram, nefazodone, tricyclic antidepressants, warfarin, fenprocoumon, dicumarol, cyclosporine, midazolam, felodipine, digoxin, methadone, theophylline, levothyroxine, praziquantel, tramadol, paracetamol, magantinib, muscle relaxants not depolarizing.
• Adjust dose.
• Increases hepatotoxicity of: isoniazid.
• Neurological adverse effects increase with: lithium, metoclopramide, neuroleptics.
• Risk of symptomatic hyponatremia with: hydrochlorothiazide, furosemide.
• Reduces tolerance to: alcohol.
• Increased toxicity with: levetiracetam.

Pregnancy and Carbamazepine

In humans there have been developmental disorders, spina bifida, craniofacial defects, cardiovascular and abnormalities in various systems.
Administer vitamin K1 to mother (last weeks) and child to avoid bleeding.

Breastfeeding

Carbamazepine passes into breast milk (approx. 25-60% of plasma concentrations).
The benefits of breastfeeding will be weighed against the remote possibility of adverse effects on the child.
Mothers taking carbamazepine may breastfeed their children provided that any adverse reactions in the child (e.g. excessive drowsiness, allergic skin reactions) are controlled.

Effects on driving ability

Carbamazepine acts on the central nervous system and can produce: drowsiness, dizziness, visual alterations and decreased ability to react.
These effects, as well as the disease itself, make it advisable to be cautious when driving vehicles or operating dangerous machinery, especially until each patient’s particular sensitivity to the medication has been established.

Adverse reactions and side effects of Carbamazepine

Dizziness, ataxia, drowsiness, fatigue.
Headache, diplopia, accommodation disorders.
Allergic skin reactions, urticaria.
Leucopenia, eosinophilia, thrombocytopenia, increased gamma-GT and alkaline phosphatase.
Nausea, vomiting, dry mouth, edema.
Weight gain, hyponatremia, reduction of plasma osmolality.

⭐⭐⭐⭐⭐ VIDEO OF CARBAMAZEPINE/TEGRETOL (DRUG)

Source: The content of this active ingredient has been written taking into account the clinical and molecular information of all medicines authorised and marketed in the United States under the Unique Ingredient Identifier (UNII) by the Substance Registration System (SRS) of the Food and Drug Administration (FDA) and the United States Pharmacopeia (USP).

In order to know in detail the information authorized by the FDA for each drug, you should consult the corresponding medication guide authorized by the FDA.

Resources:

UNII: 33CM23913M
ChemIDplus
DrugPortal
PubChem CID: 2554
NCI Thesaurus: C341