Katena capsules 300mg, 50pcs

Composition

Composition of one capsule:

• active ingredient: gabapentin 300 mg;
• auxiliary substances: corn starch, lactose monohydrate, talc;
• capsule shell: gelatin, titanium dioxide (E 171), as well as dye iron oxide yellow E 172 (capsules 300 mg), dye iron oxide yellow E 172 iron oxide red E 172 (capsules 400 mg).

Pharmacological action

An anticonvulsant drug. Gabapentin is similar in structure to the neurotransmitter GABA (GABA), but its mechanism of action differs from some other similar drugs that interact with GABA receptors, including valproate, barbiturates, benzodiazepines, GABA transaminase inhibitors, GABA uptake inhibitors, GABA agonists and prodrug forms of GABA: it does not have GABA-ergic properties and does not affect the uptake and metabolism of GABA.

Preliminary studies have shown that gabapentin binds to_{the α2}-δ subunit of voltage-dependent calcium channels and inhibits the flow of calcium ions, which plays an important role in the occurrence of neuropathic pain. Other mechanisms involved in the action of gabapentin in neuropathic pain are: a decrease in glutamate-dependent neuronal death, an increase in GABA synthesis, and suppression of the release of monoamine group neurotransmitters.

Gabapentin in clinically significant concentrations does not bind to the receptors of other common drugs or neurotransmitters, including GABA_A, GABA_B, benzodiazepine, glutamate, glycine or N-methyl-D-aspartate receptors.

Unlike phenytoin and carbamazepine, gabapentin does not interact with sodium channels.

Pharmacokinetics

Suction

The bioavailability of gabapentin is not proportional to the dose, and it decreases with increasing dose. After oral use, cmax ofgabapentin in plasma is reached in 2-3 hours. The absolute bioavailability of gabapentin in capsules is about 60%. Food, including those with a high fat content, does not affect the pharmacokinetics. The elimination of gabapentin from plasma is best described using a linear model.

The distribution

of pharmacokinetics does not change with repeated use. C_ss in plasma can be determined based on the results of a single dose of the drug. Gabapentin practically does not bind to plasma proteins (d – 57.7 l).

Metabolism

No signs of metabolism were found in humans.

The drug does not induce mixed-function oxidative liver enzymes involved in drug metabolism.

Elimination

of T_1/2 plasma does not depend on the dose and averages 5-7 hours. It is excreted exclusively by the kidneys in unchanged form.

Pharmacokinetics in special clinical cases

The clearance of gabapentin from plasma decreases in the elderly and patients with impaired renal function. The elimination rate constant, plasma clearance, and renal clearance are directly proportional to creatinine clearance. Gabapentin is removed from the plasma by hemodialysis. In patients with impaired renal function and patients receiving hemodialysis treatment, dose adjustment is recommended.

It was found that the plasma concentrations of gabapentin in children aged 4-12 years are generally similar to those in adults.

Indications

• treatment of neuropathic pain in adults (18 years and older). Efficacy and safety in patients under 18 years of age have not been established;
• monotherapy of partial seizures in epilepsy with and without secondary generalization in adults and children over 12 years of age. The efficacy and safety of monotherapy in children under 12 years of age have not been established;
• as an adjunct in the treatment of partial seizures in epilepsy with and without secondary generalization in adults and children aged 3 years and older. The safety and efficacy of gabapentin supplemental therapy in children less than 3 years of age have not been established.

Use during pregnancy and lactation

There are no data on the safety and efficacy of the drug during pregnancy, so the use of gabapentin during pregnancy is possible only if the intended benefit to the mother justifies the possible risk to the fetus.

Gabapentin is excreted in breast milk, so during treatment, you should stop breastfeeding.

Use in children

Contraindicated in children under 3 years of age.

Contraindications

• children under 3 years of age;
• hypersensitivity to gabapentin or auxiliary components of the drug.

Caution should be exercised when prescribing the drug for renal failure

Use in patients with impaired renal function

With caution, the drug should be prescribed for renal failure.

Patients on hemodialysis who have not previously taken gabapentin are recommended to take the drug in a saturating dose of 300-400 mg, and then apply it 200-300 mg every 4 hours of hemodialysis.

Side effects

From the cardiovascular system:  symptoms of vasodilation, hypertension.

From the digestive system:  dyspepsia, flatulence, nausea, vomiting, abdominal pain, constipation, diarrhea, dry mouth or throat, anorexia, gingivitis, dental diseases, increased appetite, increased activity of liver transaminases.

Musculoskeletal disorders:  myalgia, arthralgia, back pain, increased bone fragility.

Nervous system disorders:  drowsiness, dizziness, ataxia, amnesia, confusion, impaired coordination, increased fatigue, impaired thinking, tremor, hypesthesia, depression, dysarthria, insomnia, nervousness, nystagmus, increased, weakened or absent reflexes, asthenia, anxiety, hostility, hyperkinesia, emotional lability.

Respiratory system disorders:  pharyngitis, rhinitis, shortness of breath, cough, pneumonia, bronchitis, respiratory infections.

From the genitourinary system:  urinary tract infections, impotence.

From the side of the senses:  visual impairment, amblyopia, diplopia.

From the side of hematopoietic organs:  leukopenia, purpura (most often described as bruising caused by physical trauma).

Allergic reactions:  skin rash, itching, acne.

Other services:  fever, viral infection, weight gain, pain of various localization, peripheral edema, facial edema, headache.

Post-marketing experience of use

Cases of sudden unexplained death have been reported, the association of which with gabapentin treatment has not been established.

Other adverse events: acute renal failure, allergic reactions, including urticaria, alopecia, angioedema, generalized edema; fluctuations in blood glucose concentration in diabetic patients, chest pain, breast enlargement, gynecomastia, increased liver function, erythema multiforme (including Stevens-Johnson syndrome), hallucinations, motor disorders such as choreoathetosis, dyskinesia and dystonia palpitations, pancreatitis, tinnitus, thrombocytopenia, urinary incontinence, myoclonus.

Interaction

When gabapentin and morphine were co-administered, when morphine was taken 2 hours before gabapentin, there was a 44% increase in the mean gabapentin AUC compared to gabapentin monotherapy, which was associated with an increase in the pain threshold (cold pressor test). The clinical significance of this change has not been established, and the pharmacokinetic characteristics of morphine did not change. The side effects of morphine co-administered with gabapentin did not differ from those of morphine co-administered with placebo.

Interactions between gabapentin and phenobarbital, phenytoin, valproic acid, and carbamazepine were not observed. The pharmacokinetics of gabapentin at steady state are similar in healthy individuals and patients receiving other anticonvulsants.

Concomitant use of gabapentin with oral contraceptives containing norethisterone and / or ethinyl estradiol was not accompanied by changes in the pharmacokinetics of both components.

Concomitant use of gabapentin with antacids containing aluminum and magnesium is associated with a decrease in the bioavailability of gabapentin by about 20%. Gabapentin is recommended to be taken approximately 2 hours after taking the antacid.

Probenecid does not affect the renal excretion of gabapentin.

A slight decrease in the renal excretion of gabapentin with concomitant use of cimetidine is probably not clinically relevant.

How to take it, course of use and dosage

The drug Katena® is prescribed orally, regardless of food intake. If it is necessary to reduce the dose, discontinue the drug or replace it with an alternative remedy, this should be done gradually for at least one week.

Neuropathic pain in adults

The initial daily dose is 900 mg (in 3 equal doses); if necessary, depending on the effect, the dose is gradually increased to the maximum – 3.6 g/day. Treatment can be started immediately with a dose of 900 mg / day (300 mg 3 times / day). or during the first 3 days, the dose can be increased gradually to 900 mg per day according to the following scheme:

• Day 1: 300 mg 1 time/day;
• day 2: 300 mg 2 times/day;
• day 3: 300 mg 3 times/day.

Partial seizures

Adults and children over 12 years of age

The effective dose is from 900 mg to 3.6 g per day. Therapy can be started with a dose of 300 mg 3 times / day on day 1 or gradually increased to 900 mg according to the scheme described above (seesection Neuropathic pain in adults). Subsequently, the dose can be increased to a maximum of 3.6 g / day in 3 equal doses. The maximum interval between doses when taking the drug three times should not exceed 12 hours to avoid the resumption of seizures. The drug was well tolerated in doses up to 4.8 g / day.

Children aged 3-12 years

The initial dose of the drug varies from 10 to 15 mg / kg / day, which is prescribed in equal doses 3 times/day and increased to effective for approximately 3 days. The effective dose of gabapentin in children aged 5 years and older is 25-35 mg / kg / day in equal doses in 3 divided doses. The effective dose of gabapentin in children aged 3 to 5 years is 40 mg / kg / day in equal doses in 3 divided doses. Good tolerability of the drug in doses up to 50 mg / kg / day with long-term use was noted. The maximum interval between doses of the drug should not exceed 12 hours to avoid the recurrence of seizures.

There is no need to monitor the concentration of gabapentin in plasma. The drug Katena® can be used in combination with other anticonvulsants without taking into account changes in its plasma concentration or the concentration of other anticonvulsants in serum.

Dose selection for renal failure

Patients with renal insufficiency are recommended to reduce the dose of gabapentin according to the table.

* The daily dose should be administered in 3 divided doses.

* * Prescribe 300 mg every other day.

Patients on hemodialysis who have not previously taken gabapentin are recommended to take the drug in a saturating dose of 300-400 mg, and then apply it 200-300 mg every 4 hours of hemodialysis.

Overdose

Symptoms: dizziness, double vision, speech disorders, drowsiness, lethargy and diarrhea.

Treatment: gastric lavage, taking activated charcoal, symptomatic therapy. Hemodialysis may be indicated for patients with severe renal insufficiency.

Special instructions

When combined with morphine therapy, patients may experience an increase in the concentration of gabapentin. At the same time, it is necessary to ensure careful monitoring of patients for the development of such a sign of CNS depression as drowsiness. In this case, the dose of gabapentin or morphine should be adequately reduced.

When gabapentin and other anticonvulsants were co-administered, false positive results were reported when determining protein in the urine using Ames N-Multistix SG®test strips. To determine protein in the urine, it is recommended to use a more specific method of precipitation with sulfosalicylic acid.

Influence on the ability to drive motor vehicles and manage mechanisms

During the treatment period, it is necessary to refrain from driving vehicles and engaging in potentially dangerous activities that require increased concentration of attention and speed of psychomotor reactions.

Form of production

Capsules are yellow in color, size #1; the contents of the capsules are white crystalline powder.

Storage conditions

At a temperature not exceeding 25 °C

Shelf life

3 years

Active ingredient

Gabapentin

Conditions of release from pharmacies

By prescription

Dosage form

Capsules