Lamotrigine

Antiepileptic drug used in the treatment of epilepsy and bipolar disorders; has also normotime activity.

Trade names: Convulsan, Lamykal, Lamitor, Lamolep, Lamotrin, Seizar.

The mechanism of lamotrigine is not exactly known; the drug was developed as an antagonist of folic acid, but this effect was found to be weak. It is assumed that it stabilizes the neuronal membranes by affecting the sodium channels and blocks the excess release of excitatory amino acids (mainly glutamate) without reducing its normal release.

The drug is used for the following indications:

- Epilepsy (partial or generalized seizures, including tonic-clonic seizures, as well as seizures in Lennox-Gastaut syndrome in adults and children);
- bipolar disorder with predominantly depressive phases in patients aged 18 years and older.

Prolonged prophylactic monotherapy with lamotrigine in bipolar depression showed that this drug is equally effective in bipolar disorder type I and II.

The advantages of lamotrigine, allowing to justify its use at the stage of long-term prophylactic therapy, are the impact on the residual manifestations of depression, the absence of ricochetial withdrawal symptoms and the minimal presentation of side effects.

In epilepsy, lamotrigine is used in the therapy of partial epileptic seizures, primary and secondary tonic-clonic seizures and seizures associated with the Lennox-Gastaut syndrome. Can have an anticonvulsant effect when other antiepileptic drugs are ineffective.

Possible antidepressant activity of the drug is not confirmed, but it is recommended for the treatment and prevention of depressive episodes in the composition of bipolar affective disorder type I. It is suggested that in patients with depression in bipolar disorder monotherapy with antidepressants is undesirable because of a possible worsening of the course of bipolar disorder. Official recommendations published by the American Psychiatric Association recommend that from the very beginning, antidepressants should not be used as monotherapy at all in these patients; Instead of monotherapy with antidepressants, a one-stage appointment of at least combination therapy is suggested. Lamotrigine and lithium salts are recommended to be used as a "first line" at the stage of active therapy along with antidepressants.

Off-label lamotrigine is used for the treatment of depersonalization syndrome - derealization (in combination with selective serotonin reuptake inhibitors (SSRIs), schizoaffective disorder, borderline personality disorder, prolonged mental disorder caused by hallucinogens, resistant obsessive-compulsive disorder.

Outside of psychiatry, the off-label drug is also used to treat peripheral neuropathy, trigeminal neuralgia, cluster headaches, migraine, and to reduce neuropathic pain.

The drug stabilizes the presynaptic membranes of neurons and their potential-dependent sodium channels, and also blocks the release of neurotransmitters (primarily glutamate and aspartate). Glutamate, being an exciting neurotransmitter of the brain, plays a major role in the occurrence of epileptic seizures.

After ingestion lamotrigine quickly and completely absorbed from the digestive tract. Cmax is reached after about 2.5 h.

Lamotrigine has a linear pharmacokinetic profile when taken in doses up to 450 mg. The time to reach Cmax increases slightly after ingestion, but the level of absorption remains unchanged.

Lamotrigine is metabolized by the enzyme glucuronyl transferase. Does not affect the pharmacokinetics of other antiepileptic drugs.

The special value of the drug is attached to the lack of the property of causing weight gain in long-term administration, which may justify the need to transfer to it from other drugs (including lithium) patients with a tendency to obesity.

The most significant side effect of lamotrigine is skin rash, observed in about 10% of cases of prescription. There are reports of rare cases of severe, potentially life-threatening skin lesions, including Stevens-Johnson syndrome, toxic epidermal necrolysis; the drug hypersensitivity syndrome, in addition to the rash, may be accompanied by impaired blood and internal organs.

For the drug, the risk of developing drug aseptic meningitis is noted.

Among the side effects often noted are headache, dizziness, double vision, blurred vision, nausea, diarrhea, irritability, tremor, drowsiness, insomnia.

Treatment of bipolar disorders with lamotrigine is associated with an increased risk of developing suicidal thoughts or behavior.

During the treatment period, care must be taken when driving vehicles and other potentially hazardous activities that require increased concentration and speed of psychomotor reactions.

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