Composition, form of production and packaging
Tablets 1 tab.
lamotrigine * 25 mg
- "- 50 mg
- "- 100 mg
* - the non - proprietary international name recommended by WHO; in Russia it is accepted to write an international name - lamotrigine.
10 pieces. - packings cellular planimetric (5) - packs cardboard.
INSTRUCTION FOR THE SPECIALIST.
The description of the drug was approved by the manufacturer for the 2006 print edition.
PHARMACHOLOGIC EFFECT
Anticonvulsant (antiepileptic) drug. The blocker of potential-dependent sodium channels. It causes a block of pulsed discharges in the culture of neurons and inhibits the excess release of glutamate (amino acids that play a key role in the generation of epileptic seizures) along with the inhibition of glutamate-induced effector pulses.
PHARMACOKINETICS
Suction
After ingestion lamotrigine quickly and completely absorbed from the digestive tract. C max in blood plasma is observed after 2.5 В± 1.5 h after oral administration. The time to reach C max is somewhat longer in the case of taking the drug after eating, but the degree of absorption remains unchanged. Pharmacokinetics is linear in nature up to a dose of 450 mg - the maximum single dose, which was investigated. There are significant individual differences in C max drug values, but individual concentrations differ very little.
Distribution
The binding to plasma proteins is approximately 55%.
Metabolism
Metabolised in the liver with the formation of predominantly glucuronides.
Excretion
T 1/2 in healthy adults is 24-35 hours.
Mean values ​​of clearance in healthy people are 39 ± 14 ml / min.
Lamotrigine is excreted from the body with urine in the form of glucuronides. Less than 10% is excreted unchanged in the urine. Only 2% of metabolic products are excreted with feces.
Pharmacokinetics in special clinical cases
T 1/2 lamotrigine is largely dependent on concomitant drug therapy.
T 1/2 lamotrigine is reduced to 14 hours when combined with preparations inducing the activity of cytochrome P 450 isozymes, such as carbamazepine and phenytoin, and increases on average to about 70 hours in the case of concomitant use with sodium valproate.
T 1/2 of lamotrigine in children is usually shorter than in adults. T 1/2 in children is approximately 7 hours when taken with isozyme activity inducing drugs, such as carbamazepine, phenytoin, phenobarbital and primidone. T 1/2 increases to 45-55 hours when combined with sodium valproate.
The study of the pharmacokinetics of lamotrigine in single doses in patients with kidney disease indicates that the pharmacokinetic parameters vary slightly, but the concentrations of the main metabolite in the form of glucuronide increase almost 8-fold due to the decrease in renal clearance.
INDICATIONS
Lamitor is recommended as a monotherapy and auxiliary therapy for adults and children over 12 years of age:
- simple partial seizures;
- complex partial seizures;
- Secondarily generalized tonic-clonic convulsive seizures;
- Primarily generalized tonic-clonic convulsive seizures;
- Absences are typical;
- Absensities atypical;
- myoclonic seizures;
- seizures resistant to other antiepileptic drugs of any type.
Lamitor is also used as an auxiliary therapy for children aged 2 to 12 years.
DOSING MODE
The initial dose of Lamitor for adults and children over 12 years of age who do not take sodium valproate but who take other antiepileptic drugs inducing isoenzymes is 50 mg 1 time / day for the first 2 weeks and 100 mg / day (in 2 divided doses) for the following 2 weeks. Then the dose should be increased to 200-400 mg / day (in 2 divided doses).
The initial dose of Lamitor for patients taking sodium valproate in combination with other antiepileptic drugs inducing isoenzymes is 25 mg every other day for the first 2 weeks and then 25 mg 1 time / day for the next 2 weeks. Then the dose should be increased to achieve the optimal therapeutic effect. The maintenance dose is 100-200 mg (in 1 or 2 doses).
The initial dose of Lamitor for children 2 to 12 years of age who do not take sodium valproate, but who take other antiepileptic drugs inducing isoenzymes, is 2 mg / kg / day (in 2 divided doses) for the first 2 weeks and 5 mg / kg / day in 2 admission) for the next 2 weeks. The maintenance dose is 5-15 mg / kg / day (in 2 divided doses).
The initial dose of Lamitor for children taking sodium valproate in combination with other antiepileptic drugs inducing isoenzymes is 0.2 mg / kg 1 time / day for the first 2 weeks, then 0.5 mg / kg 1 time / day for the next 2 weeks. Then the dose should be increased to achieve the optimal therapeutic effect. The maintenance dose is 1-5 mg / kg (in 1 or 2 divided doses).
SIDE EFFECT
Side effects noted during the appointment of Lamitor as monotherapy
From the side of the central nervous system: dizziness, headache, drowsiness, sleep disturbance, increased fatigue.
From the side of the digestive system: nausea.
Allergic reactions: maculopapular skin rash (2%), most often observed in the first 4 weeks after the start of treatment and disappears after the drug is discontinued. In some cases - Stevens-Johnson syndrome, angioedema, toxic epidermal necrolysis.
Side effects noted when Lamitor is prescribed as an adjunct to conventional antiepileptic drugs
From the side of the central nervous system: dizziness, headache, drowsiness, imbalance, fatigue, irritability, aggressiveness, tremor, confusion.
From the side of the organ of vision: diplopia, violation of visual acuity.
From the hemopoietic system: neutropenia, leukopenia.
On the part of the digestive system: nausea, vomiting, dyspeptic phenomena.
CONTRAINDICATIONS
- pronounced violations of the liver function;
- Hypersensitivity to lamotrigine and other components of the drug.
PREGNANCY AND LACTATION
The drug should not be given during pregnancy and lactation, unless the expected benefit of therapy for the mother exceeds the potential risk to the fetus and the baby.
APPLICATION FOR FUNCTIONS OF THE LIVER
In patients with impaired renal function in the terminal stage of the disease, the accumulation of a metabolite in the form of glucuronide should be expected.Therefore, if you want to assign such patients, you should be careful.
APPLICATION FOR VIOLATIONS OF THE FUNCTION OF KIDNEYS
Contraindicated in severe violations of liver function.
APPLICATION FOR CHILDREN
The initial dose of Lamitor for children 2 to 12 years of age who do not take sodium valproate, but who take other antiepileptic drugs inducing isoenzymes, is 2 mg / kg / day (in 2 divided doses) for the first 2 weeks and 5 mg / kg / day in 2 admission) for the next 2 weeks. The maintenance dose is 5-15 mg / kg / day (in 2 divided doses).
The initial dose of Lamitor for children taking sodium valproate in combination with other antiepileptic drugs inducing isoenzymes is 0.2 mg / kg 1 time / day for the first 2 weeks, then 0.5 mg / kg 1 time / day for the next 2 weeks. Then the dose should be increased to achieve the optimal therapeutic effect. The maintenance dose is 1-5 mg / kg (in 1 or 2 divided doses).
SPECIAL INSTRUCTIONS
Information on the use of Lamitor in elderly patients is limited. Therefore, with caution should prescribe a drug of this category of patients.
If the Lamitor dose is exceeded, skin rash may develop (in this situation, the drug should be discarded).
In some cases, the appointment of the drug may develop severe skin rash (including Stevens-Johnson syndrome). Such reactions often develop in children. Lamitor should be canceled at the first signs of the appearance of the rash. The risk of developing such complications increases with the appointment of Lamitor simultaneously with sodium valproate and if the used dose of Lamitor exceeds the recommended initial and maximum daily dose.
With the development of skin rashes, the drug should be discontinued immediately.
When using Lamitor, it is possible to develop such symptoms of hypersensitivity (in some cases, up to a lethal outcome), such as fever, malaise, cold symptoms, drowsiness, lymphadenopathy, facial edema and in very rare cases - liver dysfunction, hematopoiesis (leukopenia and thrombocytopenia) . In most patients, these symptoms disappear after Lamitor's withdrawal.
If there is a rash, chills, cold symptoms, drowsiness, worsening control of convulsive seizures, especially during the first month, functional tests of the liver, kidney function, blood clotting should be monitored.
With a sharp abolition of Lamitor, there may be an increase in seizures. The dose of Lamitor should be reduced gradually within 2 weeks.
In patients with impaired renal function in the terminal stage of the disease, the accumulation of a metabolite in the form of glucuronide should be expected.Therefore, if you want to assign such patients, you should be careful.
Impact on the ability to drive vehicles and manage mechanisms
The question of the ability to drive vehicles and work with moving machinery during the reception of Lamitor is decided individually, taking into account the clinical situation.
OVERDOSE
Symptoms: nystagmus, ataxia, dizziness, drowsiness, headache, nausea, loss of consciousness, coma.
Treatment: gastric lavage, reception of activated charcoal. If necessary, conduct symptomatic therapy.
DRUG INTERACTION
When used simultaneously with antiepileptic drugs that induce isoenzymes of the liver (phenytoin, carbamazepine, phenobarbital, primidone), Lamitor metabolism is increased, which may require an increase in its dose.
Sodium valproate, which competes with lamotrigine for metabolic isoenzymes of the liver, inhibits its metabolism. There is no evidence that Lamitor is able to induce or inhibit liver isoenzymes that metabolize other drugs. Lamitor can induce its own metabolism, but this effect is very small and does not cause serious clinical manifestations.
Although some patients experience changes in the concentration of other antiepileptic drugs in plasma, controlled studies have not confirmed the effects of Lamitor on the levels of concomitant antiepileptic drugs in plasma. In vitro studies indicate that Lamitor does not compete with other antiepileptic drugs for binding sites to plasma proteins.
TERMS OF RELEASE FROM PHARMACY
The drug is released by prescription.
TERMS AND CONDITIONS OF STORAGE
The drug should be stored in a place protected from light and moisture at a temperature of no higher than 30 В° C. Shelf life - 2 years.
