Catena

General characteristics. Structure:

Capsules of 100 mg:
Active agent: габапентин — 100 mg;

Excipients: lactoses monohydrate, starch corn, talc;

Capsular cover: titanium dioxide (Е 171), gelatin.

Capsules of 300 mg:
Active agent: габапентин - 300 mg;

Excipients: lactoses monohydrate, starch corn, talc;

Capsular cover: titanium dioxide (Е 171), dye ferrous oxide yellow (Е 172), gelatin.

Capsules of 400 mg:
Active agent: габапентин - 400 mg;

Excipients: lactoses monohydrate, starch corn, talc;

Capsular cover: titanium dioxide (Е 171), dye ferrous oxide yellow (Е 172), dye ferrous oxide red (Е 172), gelatin.

Pharmacological properties:

Pharmacodynamics. Gabapentin on a structure is similar to the neurotransmitter gamma аминомаслянной acid (GAMK), however its mechanism of action differs from that some other drugs interacting with GAMK-receptors including Valproatum, barbiturates, benzodiazepines, GAMK-transaminase inhibitors, inhibitors of capture of GAMK, agonists of GAMK and pro-dosage forms of GAMK: it has no GAMK-ergichesky properties and does not influence for capture and metabolism of GAMK. Preliminary researches showed what габапентин communicates with α2-δ-субъединицей a voltage - dependent calcium channels and the flow of calcium ions playing an important role in developing of neyropatichesky pain suppresses.
Other mechanisms participating in operation a gabapentina at neyropatichesky pain are: reduction a glutamate - dependent death of neurons, increase in synthesis of GAMK, suppression of release of neurotransmitters of monoamine group.
Gabapentin in clinically significant concentration does not contact receptors of other widespread drugs or neurotransmitters, including receptors of GAMKA, GAMKV, benzodiazepine, a glutamate, glycine or N-methyl-D-aspartate. Unlike Phenytoinum and carbamazepine габапентин does not interact with natrium channels.

Pharmacokinetics. Absorption
Bioavailability of a gabapentin is not proportional to a dose; so, at increase in a dose it decreases. After intake the maximum concentration (Cmax) of a gabapentin in plasma is reached in 2-3 h. Absolute bioavailability of a gabapentin in capsules makes about 60%. Food, including with high content of fats, does not exert impact on pharmacokinetics. Removal of a gabapentin from plasma is best of all described by means of linear model.
Distribution
The pharmacokinetics does not change at repeated use; equilibrium concentration in plasma can be predicted on the basis of results of a single dose of drug.
Gabapentin practically does not contact proteins of plasma (<3 %) and has the volume of distribution of 57,7 l.
Metabolism
Metabolism signs at the person are not revealed. Drug does not induce the oxidizing enzymes of a liver with the mixed function participating in metabolism of medicines.
Removal the Elimination half-life (T1/2) from plasma does not depend on a dose and averages 5-7 h.
It is removed only by kidneys in not changed look.

Pharmacokinetics in special clinical cases. The clearance of a gabapentin from plasma decreases at elderly people and patients with an impaired renal function. The removal speed constant, clearance from plasma and renal clearance are directly proportional to clearance of creatinine. Gabapentin leaves from plasma at a hemodialysis. At patients with an impaired renal function and the patients receiving treatment by a hemodialysis dose adjustment is recommended (see the Route of administration and doses).
It is established that concentration of a gabapentin in plasma at children aged from 4 up to 12 years in general are similar to those at adults.

Indications to use:

Treatment of neyropatichesky pain at adults (18 years are also more senior). Efficiency and safety at patients aged up to 18 years are not established.
Monotherapy of partial spasms at epilepsy with secondary generalization and without it at adults and children is aged more senior than 12 years. Efficiency and safety of monotherapy at children aged up to 12 years are not established.
As the additional tool at treatment of partial spasms at epilepsy with secondary generalization and without it at adults and children at the age of 3 years is also more senior. Safety and efficiency of additional therapy gabapentiny at children at the age of less than 3 years are not established.

Route of administration and doses:

The drug KATENA® is appointed inside, irrespective of meal. If it is necessary to lower a dose, to cancel drug or to replace it with alternative means, it should be done gradually within at least one week.

Neyropatichesky pain at adults.
The initial dose makes 900 mg a day in three steps equal doses; if necessary, depending on effect, the dose is gradually increased to maximum - 3600 mg/days. Treatment it is possible to begin with a dose 900 mg/days at once (on 300 mg 3 times a day) or during the first 3 days it is possible to increase a dose gradually to 900 mg a day according to the following scheme:
1st day: 300 mg of 1 times a day
2nd day: on 300 mg 2 times a day
3rd day: on 300 mg 3 times a day

Partial spasms
Adults and children are aged more senior than 12 years:
Effective dose - from 900 to 3600 mg a day. Therapy it is possible to begin with a dose 300 mg 3 times a day in the first day or to increase gradually up to 900 mg according to the scheme described above (see the section "Neyropatichesky Pain at Adults"). In the subsequent the dose can be increased to maximum - 3600 mg/days in three steps by equal doses. The maximum interval between doses at triple administration of drug should not exceed 12 h in order to avoid resuming of spasms. Good tolerance of drug in doses to 4800 mg/days is noted.

Children at the age of 3-12 years: The initial dose of drug varies from 10 to 15 mg/kg/days; which is appointed by equal doses by 3 times a day and raise to effective approximately within 3 days. The effective dose of a gabapentin at children at the age of 5 years is also more senior makes 25-35 mg/kg/days equal doses in 3 receptions. The effective dose of a gabapentin at children aged from 3 up to 5 years makes 40 mg/kg/days equal doses in three steps. Good tolerance of drug in doses to 50 mg/kg/days at prolonged use is noted. The maximum interval between reception of doses of drug should not exceed 12 hours in order to avoid resuming of spasms.

There is no need to control concentration of a gabapentin in plasma. The drug KATENA® can be used in a combination with other anticonvulsant drugs without change of its concentration in plasma or concentration of other anticonvulsant drugs in serum.

Selection of a dose at a renal failure
The dose decline of a gabapentin according to the table is recommended to patients with a renal failure:

Clearance of creatinine (ml/min.)	Daily dose (mg/days) *
> 80	900-3600
50-79	600-1800
30-49	300-900
15-29	150**-600
<15	150**-300

* It is necessary to appoint a daily dose in three steps.
** Appoint 300 mg every other day.

Recommendations for the patients who are on a hemodialysis
To the patients who are on a hemodialysis who did not accept габапентин earlier drug is recommended to appoint 300-400 mg in the sating dose, and then to apply it on 200-300 mg each 4 h a hemodialysis.

Features of use:

At joint therapy by morphine at patients can occur increase in concentration of a gabapentin. At the same time it is necessary to provide careful observation of patients regarding development of such sign of oppression of the central nervous system (CNS) as drowsiness. In this case the dose of a gabapentin or morphine has to be adequately lowered (see. "Interaction with other medicines").
Laboratory researches
At combined use of a gabapentin and other anticonvulsants positive takes when determining protein in urine by means of test strips of Ames N-Multistix SG® were registered in a false manner. For definition of protein in urine it is recommended to use more specific method of precipitation sulphosalicylic acid.

Influence on ability of control of vehicles and mechanisms
During treatment it is necessary to refrain from driving of motor transport and occupations potentially dangerous types of activity demanding the increased concentration of attention and speed of psychomotor reactions.

Side effects:

From cardiovascular system: vazodilatation symptoms, hypertensia.
From the alimentary system: dyspepsia, a meteorism, nausea, vomiting, an abdominal pain, a lock, diarrhea, dryness in a mouth or a throat, anorexia, an ulitis, diseases of teeth, increase in appetite, increase in activity of "hepatic" transaminases,
From a musculoskeletal system: a mialgiya, an arthralgia, a dorsodynia, the increased fragility of bones.
From a nervous system: drowsiness, dizziness, ataxy, amnesia, confusion of consciousness, lack of coordination, increased fatigue, disturbance of thinking, tremor, hypesthesia, depression, dysarthtia, sleeplessness, nervousness, nystagmus, strengthening, easing or lack of reflexes, adynamy, uneasiness, hostility, hyperkinesia, emotional lability.
From respiratory system: pharyngitis, rhinitis, short wind, cough, pneumonia, bronchitis, respiratory infections.
From urinogenital system: infections of uric ways, impotence.
From sense bodys: vision disorder, amblyopia. diplopia.
From bodies of a hemopoiesis: a leukopenia, a purpura (most often it is described as the bruises arising at a physical injury).
Allergic reactions: skin rash, itch, acne.
Others: fever, viral infection, increase in body weight, pain of various localization, peripheral hypostases, face edema, headache.
Post-registration experience of use
Cases of sudden inexplicable death which connection with treatment gabapentiny is not established are registered.
Other undesirable phenomena: an acute renal failure, allergic reactions, including a small tortoiseshell, an alopecia, a Quincke's disease, generalized hypostasis; fluctuations of concentration of glucose in blood at patients with a diabetes mellitus, a stethalgia, increase in volume of mammary glands, a gynecomastia, increase in indicators of function of a liver, a multiformny exudative erythema (including Stephens-Johnson's syndrome), hallucinations, motive frustration, such as a choreoathetosis, dyskinesia and dystonia, heartbeat, pancreatitis, a sonitus, thrombocytopenia, an urine incontience, a myoclonus.

Interaction with other medicines:

At simultaneous use of a gabapentin and morphine when morphine was accepted in 2 hours prior to reception of a gabapentin, increase in average value of the area under a pharmacokinetic curve "concentration - time" (AUC) of a gabapentin for 44% in comparison with monotherapy gabapentiny was observed that was associated with increase in a pain threshold (the holodovy pressor test). Clinical value of this change is not established, pharmacokinetic characteristics of morphine at the same time did not change.
Side effects of morphine at joint reception with gabapentiny did not differ from those at reception of morphine together with placebo.
Interaction between gabapentiny and phenobarbital, Phenytoinum, valproic acid and carbamazepine is noted. The pharmacokinetics of a gabapentin in an equilibrium state is identical at the healthy people and patients receiving other anticonvulsants.
Simultaneous use of a gabapentin with the oral contraceptives containing Norethisteronum and/or ethinylestradiol was not followed by changes of pharmacokinetics of both components.
Simultaneous use of a gabapentin with the antacids containing aluminum and magnesium is followed by decrease in bioavailability of a gabapentin approximately for 20%.
Gabapentin is recommended to accept approximately in 2 h after reception of an antacid.
Probenetsid does not influence renal excretion of a gabapentin.
Small decrease in renal excretion of a gabapentin at a concomitant use of Cimetidinum has probably no clinical value.

Contraindications:

Hypersensitivity to a gabapentin or auxiliary components of drug. Children's age up to 3 years.

With care
Renal failure (see. "Route of administration and doses").

Pregnancy and period of a lactation
Pregnancy
Data on safety and efficiency of use of drug at pregnancy are absent therefore use of a gabapentin at pregnancy is possible only if the estimated advantage for mother justifies possible risk for a fruit.
Lactation
Gabapentin is brought with breast milk therefore during treatment it is necessary to refuse breastfeeding.

Overdose:

Symptoms: dizziness, doubling in eyes, disturbance of the speech, drowsiness, a lethargy and diarrhea.
Treatment: gastric lavage, reception of absorbent carbon, symptomatic therapy.
The hemodialysis can be shown to patients with a heavy renal failure.

Storage conditions:

At a temperature not above 25 °C.
To store in the place, unavailable to children!

Issue conditions:

According to the recipe

Packaging:

Capsules of 100 mg: On 10 capsules in PVC / It is scarlet the blister. Two blisters place together with the application instruction in a cardboard pack.
Capsules of 300 mg and 400 mg: On 10 capsules in PVC / It is scarlet the blister. Five blisters place together with the application instruction in a cardboard pack.