OGEN 25 mg
Tablets

Anticonvulsants

  • Chemical Composition

    Lamotrigine 25 mg

  • Packing

    20Tablets

  • Medical Id

    T75

  • License Number

    356/2009

  • License date

    28/12/2009

Mechanism Of Action The precise mechanism(s) by which lamotrigine exerts its anticonvulsant action are unknown. One proposed mechanism of action of LAMOTRIGINE involves an effect on sodium channels. In vitro pharmacological studies suggest that lamotrigine inhibits voltage-sensitive sodium channels, thereby stabilizing neuronal membranes and consequently modulating presynaptic transmitter release of excitatory amino acids (e.g., glutamate and aspartate).
INDICATIONS Lamotrigine is used alone or in combination with other medications to treat seizures in adults. Lamotrigine is also used to delay mood episodes in adults with bipolar disorder. Epilepsy Adjunctive Use LAMOTRIGINE is indicated as adjunctive therapy for partial seizures, the generalized seizures of Lennox-Gastaut syndrome, and primary generalized tonic-clonic seizures in adults. Monotherapy Use LAMOTRIGINE is indicated for conversion to monotherapy in adults with partial seizures who are receiving treatment with carbamazepine, phenytoin, phenobarbital, primidone, or valproate as the single AED. LAMOTRIGINE is indicated for the maintenance treatment of Bipolar I Disorder to delay the time to occurrence of mood episodes (depression, mania, hypomania, mixed episodes) in patients treated for acute mood episodes with standard therapy. The physician who elects to use LAMOTRIGINE for periods extending beyond 18 months should periodically re-evaluate the long-term usefulness of the drug for the individual patient.
CONTRAINDICATIONS LAMOTRIGINE is contraindicated in patients who have demonstrated hypersensitivity to the drug or its ingredients.
Side EFFECTS This medication may cause severe or life-threatening skin rash, especially in children. Serious skin rash may also be more likely to occur if taking lamotrigine together with valproic acid (Depakene) or divalproex (Depakote). Seek emergency medical attention if there is a fever, sore throat, swollen glands, and headache with a severe blistering, peeling, and red skin rash. Emergency medical help must be sought if any sign of an allergic reaction appears; these signs include hives; difficulty breathing; swelling of your face, lips, tongue, or throat. The most serious side effects include the first sign of any skin rash; chest pain; sudden bruising or bleeding; pale skin, fever, chills, body aches, flu symptoms; or nausea, stomach pain, low fever, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes). Less serious side effects may be more likely to occur, such as: dizziness or drowsiness; blurred vision; ataxia, nausea, vomiting, diarrhea, upset stomach; headache; lack of coordination; weight loss; anxiety, sleep problems (insomnia), unusual dreams; or runny or stuffy nose.
WARNINGS Severe, potentially life-threatening rashes have been reported in association with the use of lamotrigine. These reports, occurring in approximately one in every thousand adults, have included Stevens-Johnson syndrome and, rarely, toxic epidermal necrolysis. Rare deaths have been reported. Nearly all cases of serious rashes associated with lamotrigine have occurred within 2 to 8 weeks of treatment initiation. However, isolated cases have been reported after prolonged treatment (e.g., 6 months). Accordingly, duration of therapy cannot be relied upon as a means to predict the potential risk signalled by the first appearance of a rash. Hypersensitivity Reactions: Rash has also been reported as part of a hypensenstitivity syndrome associated with a variable pattern of systemic symptoms including fever, lymphadenopathy, facial edema and abnormalities of the blood and liver. If such signs and symptoms are present, the patient should be evaluated immediately and lamotrigine discontinued. Prior to initiation of treatment with lamotrigine, the patient should be instructed that a rash or other signs or symptoms of hypersensitivity (e.g., fever, lymphadenopathy) may herald a serious medical event and that the patient should report any such occurrence to a physician immediately. Drug Discontinuation: In general, withdrawal of an AED should be gradual to minimize provoking rebound seizures. Unless safety concerns require a more rapid withdrawal, the dose of lamotrigine should be tapered over a period of at least 2 weeks. Occupational Hazards: Patients with uncontrolled epilepsy should not drive or handle potentially dangerous machinery. During clinical trials common adverse effects included dizziness, ataxia, drowsiness, diplopia and blurred vision. Patients should be advised to refrain from activities requiring mental alertness or physical coordination until they are sure that lamotrigine does not affect them adversely. Antiepileptic Drugs (AEDs): Antieplieptic drugs that induce hepatic drug-metabolizing enzymes (phenytoin, carbamazepine, phenobarbital, primidone) increase the plasma clearance and reduce the elimination half-life of lamotrigine. Valproic acid reduces the plasma clearance and prolongs the elimination half-life of lamotrigine. However the addition of lamotrigine did not affect the plasma concentration of valproic acid in patients receiving enzyme-inducing AEDs in combination with valproic acid. Oral Contraceptives: In a study of 12 female volunteers, lamotrigine did not affect plasma concentrations of ethinyl estradiol and levonorgestrel following administration of the oral contraceptive pill. However, as with the introduction of other chronic therapy in patients taking oral contraceptives, the patient should be asked to report any change in the menstrual bleeding pattern. Geriatrics: Caution should be exercised in dose selection for an elderly patient, recognizing the more frequent hepatic, renal and cardiac dysfunctions and limited experience with lamotrigine in this population. Children: The safety and efficacy of lamotrigine in children under 18 years of age have not yet been established. Renal Failure: Use of lamotrigine in patients with severe renal impairment should proceed with caution. Impaired Liver Function: Caution should be exercised in dose selection for patients with this condition. Cardiac Conduction Abnormalities: Lamotrigine should be used with caution in patients with cardiac conduction abnormalities, and in patients taking concomitant medications which depress AV conduction.
Pregnancy And lactations Pregnancy: lamotrigine should only be used during pregnancy if the benefits of therapy outweigh the risks associated with it. Lactation: Lamotrigine is excreted in human milk. Because of the potential for adverse reactions from lamotrigine in nursing infants, breast-feeding while taking this medication is not recommended
Dosage And Administration Oral Contraceptives: Oral contraceptives may decrease the serum concentration of lamotrigine. Dosage adjustment of lamotrigine may be required when starting/stopping oral contraceptives. Carbamazepine, Phenobarbital, Primidone, and Phenytoin: The addition of carbamazepine, phenobarbital, primidone, or phenytoin decreases lamotrigine steady-state concentrations by approximately 40%. Folate Inhibitors: Lamotrigine is a weak inhibitor of dihydrofolate reductase. Prescribers should be aware of this action when prescribing other medications that inhibit folate metabolism. Rifampin: Rifampin significantly increases the clearance of lamotrigine by approximately 2-fold (AUC decreased by approximately 40%). Topiramate: Topiramate resulted in no change in plasma concentrations of lamotrigine. Administration of Lamotrigine resulted in a 15% increase in topiramate concentrations. Valproate: The addition of valproate increases lamotrigine steady-state concentrations by slightly more than 2-fold. Known Inducers or Inhibitors of Glucuronidation: Since lamotrigine is metabolized predominately by glucuronic acid conjugation, drugs that are known to induce or inhibit glucuronidation may affect the apparent clearance of lamotrigine and doses of lamotrigine may require adjustment based on clinical response. Drug \ Clinical Laboratory Test Interactions: None known
OVERDOSE : Overdoses involving quantities up to 15 g have been reported for Lamotrigine, some of which have been fatal. Overdose has resulted in ataxia, nystagmus, increased seizures, decreased level of consciousness, coma, and intraventricular conduction delay. There are no specific antidotes for Lamotrigine. Following a suspected overdose, hospitalization of the patient is advised. General supportive care is indicated, including frequent monitoring of vital signs and close observation of the patient. If indicated, emesis should be induced or gastric lavage should be performed; usual precautions should be taken to protect the airway. It should be kept in mind that lamotrigine is rapidly absorbed.
Storage Conditions Store below 30 c Keep out of reach of children