Carbamazepine

General characteristics. Structure:

Active ingredient: 200 mg of carbamazepine.

Excipients: cellulose microcrystallic, sodium glikolit starch, povidone, magnesium stearate, sodium lauryl sulfate.

Medicine with the expressed anticonvulsant action, and also moderate anti-maniacal, antipsychotic and analgeziruyushchy action at neurogenic pains.

Pharmacological properties:

Pharmacodynamics. Anticonvulsant drug, derivative tricyclic iminostilbene. Anticonvulsant action is connected with decline in the ability of neurons to support the high frequency of development of repeated action potentials by means of an inactivation of natrium channels. Carbamazepine also has moderate anti-maniacal, antipsychotic effect, and also analgeziruyushchy action at neurogenic pains. In action mechanisms, perhaps, receptors gamma аминобутировой acids which can be connected with calcium channels are involved; also, apparently, influence of carbamazepine on systems of modulators of neurotransfer matters. Antidiuretic effect of Carbamazepine is connected with hypothalamic influence on osmoreceptors which is mediated through secretion of antidiuretic hormone, and also direct action on renal tubules. Prevents attacks of an epileptiform neuralgia, reduces expressiveness of clinical manifestations of alcoholic abstinence and reduces convulsive activity. At not diabetes mellitus lowers a diuresis and feeling of thirst.

Pharmacokinetics. It is soaked up slowly from digestive tract. Almost it is completely metabolized. The maximum concentration in plasma comes in 8-12 hours. Contacts blood proteins for 70-80%. In cerebrospinal fluid and saliva concentration in proportion to a share of active agent, incoherent with proteins (20-30%) are created. The elimination half-life of 30-40 hours, at prolonged use decreases till 10-20 o'clock. Gets into breast milk (25-60% of level in plasma) and through a placental barrier. It Biotransformirutsya in a liver with formation of several metabolites. It is removed in a small amount with breast milk. The beginning of anticonvulsant action varies from several hours to several days (sometimes up to 1 month). The antineuralgic effect develops in 8-72 hours, anti-maniacal – 7-10 days later.

Indications to use:

- difficult symptomatology (psychomotor attacks); big attacks, generally focal genesis (big attacks during sleep, diffusion big attacks); the mixed epilepsy forms;

 - epileptiform neuralgia;

 - the pristupoobrazny pains of the unknown reason arising on the one hand a root of language, a throat and a soft palate (genuinical glossofaringealny neuralgia);

 - pains at defeats of peripheral nerves at a diabetes mellitus (pain at a diabetic neuropathy);

 - epileptiform spasms at multiple sclerosis, as, for example, spasms of facial muscles at an epileptiform neuralgia, tonic spasms, pristupoobrazny disturbances of the speech and movements (a paroxysmal dysarthtia and an ataxy), unpleasant feelings (paroxysmal paresthesias) and pain attacks;

 - the prevention of development of convulsive attacks at an alcoholic abstinence syndrome;

 - psychoses (generally at maniac-depressive states, hypochiondrial depressions). Secondary prevention of affective and schizoaffective psychoses.

Route of administration and doses:

Inside, in time or after food, washing down with a small amount of liquid.

Epilepsy.
Adult: in an initiation of treatment of 0,1-0,2 g 1-2 times a day, then increase a dose by 0,2 g a day with an interval of 1 week, a maintenance dose – 0,6 – 1,2 g/days in stages. The maximum daily dose for adults and children is more senior than 15 years – 1,2 g a day. To children: 10-20 mg/kg: till 1 year – 0,1-0,2 g a day, from 1 to 5 years – 0,2-0,4, in days, 5-10 years – 0,4-0,6 g a day, 10-15 years – 0,6-1,0 g a day. The daily dose is divided in stages.

Pain syndrome of neurogenic genesis.
On 0,1 g 2 times a day in the first day, then a dose increase no more than by 0,2 g a day (if necessary – on 0,1 g each 12 hours) before easing of pains. a maintenance dose – 0,2-1,2 g a day in stages.

Epileptiform neuralgia.
0,2-0,4 g/days in 2-3 receptions, in 2-3 days increase a dose by 0,1-0,2 g/days. Treatment is continued within 7-10 days. After achievement of optimum therapeutic effect the drug dose is gradually reduced to supporting.

Diabetic neuropathy
On 0,2 g 2-3 times a day.

Not diabetes mellitus.
On 0,2 g 2-3 times a day.

Syndrome of alcoholic abstinence.
On 0,2 g 3 times a day.

As antipsychotic means.
0,2-0,4 g a day in stages. If necessary the dose is increased to 1,6 g a day with an interval of 1 week.

Prevention of a recurrence of affective and schizoaffective psychoses.
0,6 g in 3-4 receptions.

Features of use:

Before the beginning and in the course of therapy regular blood tests (cellular elements) and urine, control of indicators of function of a liver are recommended.

With care appoint in the presence in the anamnesis of heart diseases, a liver, kidneys, at hematologic disturbances, the increased intraocular pressure, latent psychoses, excitement, diseases which are characterized by spasms at advanced age, to the drivers of transport and persons working with mechanisms.

Additional reception of folic acid (before approach of pregnancy is recommended to women or during it); for the purpose of prevention of the raised bleeding in recent weeks of pregnancy and at newborns vitamin K use is possible.

Pregnancy and feeding by a breast. There are some data on teratogenic influence on a fruit. Use of drug during pregnancy demands especially careful control. The by-effects arising at the child when breastfeeding: lethargy (rarely) and loss of appetite.

Side effects:

Carbamazepine is the antiepileptic means causing the smallest number of side effects. However in some cases the ataxy, dizziness, disorders of accommodation, drowsiness, dryness in a mouth, diarrhea develop. Allergic reactions (rash, Stephens-Johnson's syndrome), a hair loss, a leukopenia are possible. Seldom, especially at elderly persons, disorders of cordial conductivity, hematologic changes, cholestatic hepatitis, hypostases and increase in body weight can be observed, increase of spasms is in some cases possible. All these reactions are the indication to drug withdrawal. At elderly, especially in an initiation of treatment, there can be a confusion of consciousness that usually passes spontaneously in 1-2 weeks or after reduction of a dose.

Interaction with other medicines:

Carbamazepine stimulates metabolism of cyclosporine, an Ethosuximidum, felodipin and warfarin that leads to reduction of time of effect of these drugs.

Danazol, dextropropoxyphene, erythromycin, an isoniazid and verapamil inhibit carbamazepine metabolism owing to what there can be unexpectedly strong action or side effects of carbamazepine.

At some patients diltiazem reduces carbamazepine metabolism that leads to increase in its concentration in a blood plasma. Barbiturates accelerate carbamazepine elimination. Cisplatinum and doxorubicine reduce absorption of carbamazepine and reduce its content in plasma.

Contraindications:

Atrioventricular block. Treatment by MAO inhibitors within 14 days before an initiation of treatment carbamazepine. Liver failure. Acute returnable porphyria.

Overdose:

Symptoms: a disorientation, drowsiness, excitement, hallucinations, sight misting, a nystagmus, an ataxy, spasms, a myoclonus, respiratory depression, a fluid lungs, tachycardia, a cardiac standstill, the followed potereysoznaniya, decrease in motility of a large intestine, a hyponatremia, a hyperglycemia, the metabolic acidosis is possible.

Treatment: gastric lavage, purpose of absorbent carbon and salt laxative, artificial diuresis. For maintenance of passability of respiratory tracts – an artificial respiration and (or) use of oxygen. It is necessary to expect repeated strengthening symptomatic of overdose for the 2nd and 3rd day after its beginning that is connected with slow absorption of drug.

Storage conditions:

List B. In dry, protected from mestepra light to temperature not higher than 25 ºС. To store in the place, unavailable to children. Period of validity 3 years.

Issue conditions:

According to the recipe

Packaging:

On 30 or 50 tablets in plastic cases or in banks polymeric for packaging of medicines. On 10 tablets in a blister strip packaging. A case, to bank, 3 or 5 blister strip packagings together with a leaf insert in secondary packaging.