Anticonvulsants in epilepsy: a review of remedies

Anticonvulsants, to date, are represented by a fairly large group of funds, but the search and development of new drugs. This is due to the variety of clinical manifestations of epilepsy. After all, there are many varieties of seizures with different mechanisms of development. The search for innovative means is also conditioned by the resistance (resistance) of epileptic seizures to some existing drugs, the presence of side effects that complicate the life of the patient and some other aspects. From this article, you will learn about the main antiepileptic drugs and features of their application.

Some basics of epilepsy pharmacotherapy

The main purpose of the treatment of epilepsy is to preserve and improve the quality of life of the patient. This tries to achieve with the helpfull eliminate epileptic seizures. But at the same time, the side effects that have developed from constant medication should not exceed the negative effects of seizures. That is impossible to achieve the elimination of seizures "at any price". It is necessary to find a "middle ground" between the manifestations of the disease and the adverse effects of antiepileptic drugs: so that the number of seizures decreased, and the side effects were minimal.

The choice of antiepileptic agent is determined by several parameters:

  • the clinical form of attack;
  • type of epilepsy (symptomatic, idiopathic, cryptogenic);
  • patient's age, sex, weight;
  • the presence of comorbidities;
  • lifestyle.

Before the attending physician is a difficult task: out of an abundance of anti-epileptics to pick up (and it would be nice, the first attempt) effective tool. Moreover, monotherapy of epilepsy is desirable, that is, the use of one drug. Only in cases where several drugs, in turn, are not able to cope with the attacks, resort to simultaneous administration of two or even three drugs. Recommendations for the use of individual drugs based on their effectiveness in a particular form of epilepsy and types of seizures. In this regard, there are first-and second-line drugs of choice, that is, those with which you want to start treatment (and the probability of their effectiveness is higher), and those that should be resorted to in the case of inefficiency of first-line drugs.

The complexity of the selection of the drug is largely dependent on the availability of its individual (!) effective dose and tolerability. That is, two patients with the same types of seizures, the same sex, weight, and approximately the same age, and even the same comorbidities, may require a different dose of the same drug to control the disease.

It should also be borne in mind that the drug should be used for a long time without interruption: after establishing control over the attacks for another 2-5 years! Unfortunately, sometimes it is necessary to take into account the material possibilities of the patient.

How do anticonvulsants work?

The occurrence of seizures in epilepsy is the result of the abnormal electrical activity of the cerebral cortex: epileptic focus. Reduction of excitability of neurons of the epileptic focus, stabilization of membrane potentials of these cells leads to a decrease in the number of spontaneous discharges and, accordingly, to a decrease in the number of seizures. Here in this direction and "work" antiepileptic drugs.

There are three main mechanisms of action of anticonvulsants:

  • stimulation of GABA receptors. GABA-gamma-aminobutyric acid - is an inhibitory mediator of the nervous system. Stimulation of its receptors leads to inhibition of neuronal activity;
  • blockade of ion channels in the neuron membrane. The occurrence of electric discharge is associated with a change in the action potential of the cell membrane, and the latter occurs at a certain ratio of sodium, calcium, potassium ions on both sides of the membrane. Changing the ratio of ions leads to a decrease in epi activity;
  • reducing the amount of glutamate or blocking its receptors in the synaptic cleft (at the point of transmission of an electric discharge from one neuron to another). Glutamate is a neurotransmitter with an excitatory type of action. Elimination of its effects allows localizing the focus of excitation, not allowing it to spread to the entire brain.
  • Each anticonvulsant may have one or more mechanisms of action. Side effects from the use of antiepileptic drugs are also associated with these mechanisms of action since they realize their capabilities not selectively, but, in fact, in the entire nervous system (and sometimes not only in it).

    Main anticonvulsant drugs

    Epilepsy has been treated with a variety of drugs since the XIX century. The choice of certain drugs changes over time due to the emergence of new data on their use. Several drugs have sunk into the past, and some still retain their positions. Currently, among anticonvulsants the most common and commonly used are the following drugs:

    • Sodium valproate and other valproates;
    • Carbamazepine;
    • Oxcarbazepine;
    • Lamotrigine;
    • Ethosuximide;
    • Topiramate;
    • Gabapentin;
    • Pregabalin;
    • Phenytoin;
    • Phenobarbital;
    • Levetiracetam.

    Naturally, this is not the whole list of existing anticonvulsants. Only in the United States, today, registered and allowed to use more than 30 drugs.

    Separately, it should be noted that in the treatment of epilepsy of great importance is the fact that the original (branded) drug or generic (generic). The original drug is a drug that was created for the first time, has been tested and patented. Generic-a drug with the same active substance, but produced repeatedly, by another company and after the expiration of the patent of the brand. Excipients and manufacturing technology in the generic may differ from the original. So, in the case of treatment of epilepsy, the use of a brand or generic plays an important role, since it has been noted that when transferring a patient from the original drug to a generic (usually due to financial difficulties, since branded drugs are very expensive), it may be necessary to adjust the dose of the latter (more often upwards). Also, when using generics, the frequency of side effects usually increases. As you can see, the equivalence of drugs, in this case, can not speak. Therefore, in the treatment of epilepsy, it is impossible to change one drug to another with a similar active substance without consulting a doctor.

    A list of available drugs for epilepsy, you can continue onwards, as the ideal medicine does not exist yet (too many nuances in the treatment of epileptic seizures). Attempts to create a "gold standard" for the treatment of this disease continue.

    Summarizing the above, I would like to clarify that any drug from anticonvulsants is not harmless. It should be remembered that the treatment should be carried out only by a doctor, no independent choice or change of the drug is out of the question!