Composition, form of production and packaging
Capsules hard gelatinous, size в„–0, white; the contents of the capsules are white or white with a yellowish tinge powder.
1 caps.
gabapentin 300 mg
Excipients: calcium stearate 4.2 mg, sodium carboxymethyl starch (type A) 4.2 mg, microcrystalline cellulose 111.6 mg.
Composition of the capsule: gelatin, titanium dioxide.
10 pieces. - packings cellular planimetric (5) - packs cardboard.
15 pcs. - packings cellular planimetric (3) - packs cardboard.
50 pcs. - polymer cans (1) - packs of cardboard.
100 pieces. - polymer cans (1) - packs of cardboard.
INSTRUCTION FOR THE SPECIALIST.
Description of the drug approved by the manufacturer for the printed edition of 2011.
PHARMACHOLOGIC EFFECT
Gabapentin is similar in structure to the neurotransmitter gamma-aminobutyric acid (GABA), but its mechanism of action differs from other drugs interacting with GABA receptors (valproic acid, barbiturates, benzodiazepines, GABA transaminase inhibitors, GABA-capture inhibitors, GABA agonists and prodrug forms GABA). It does not possess GABA-ergic properties and does not affect the capture and metabolism of GABA. Preliminary studies have shown that gabapentin binds to? 2 -? - subunit of voltage-dependent calcium channels and reduces the flow of calcium ions, which plays an important role in the occurrence of neuropathic pain.Other mechanisms of action of gabapentin in neuropathic pain are a decrease in glutamate-dependent neuronal death, an increase in GABA synthesis, suppression, release of the neurotransmitters of the monoamine group. Gabapentin does not bind to receptors of other common drugs or neurotransmitters, including GABA A , GABA B , benzodiazepine, glutamate, glycine or N-methyl-D-aspartate receptors in clinically significant concentrations. Unlike phenytoin and carbamazepine, gabapentin does not interact with sodium channels in vitro . Gabapentin partially attenuated the effects of the glutamate receptor agonist N-methyl-D-aspartate in somein vitro tests, but only at a concentration of more than 100 Ојmol, which is not achieved in vivo . Gabapentin somewhat reduces the release of monoamine neurotransmitters in vitro .
PHARMACOKINETICS
The bioavailability of gabapentin is not proportional to the dose. So, with an increase in the dose, it decreases. After ingestion of C max, gabapentin in plasma is reached after 2-3 hours. Absolute bioavailability of gabapentin in capsules is about 60%. Food, incl. with a high fat content, does not affect the pharmacokinetics. The elimination of gabapentin from plasma is best described using a linear model. T 1/2 from the plasma is dose-independent and averages 5-7 hours. Pharmacokinetics does not change with repeated application; equilibrium concentrations in plasma can be predicted based on the results of a single dose of the drug. Gabapentin practically does not bind to plasma proteins (<3%) and has a V d of 57.7 l. It is excreted exclusively by the kidneys in unchanged form, it is not metabolized. The drug does not induce oxidative liver enzymes with a mixed function involved in the metabolism of drugs. The clearance of gabapentin from plasma decreases in elderly people and in patients with impaired renal function. The rate of elimination constant, clearance from plasma and renal clearance are directly proportional to the creatinine clearance. Gabapentin is removed from the plasma during hemodialysis. In patients with impaired renal function and patients receiving hemodialysis treatment, dose adjustment is recommended.
INDICATIONS
- monotherapy or as an additional agent for the treatment of partial seizures with secondary generalization or without it in adults and children from the age of 12;
- Neuropathic pain in adults (18 years and older).
DOSING MODE
Inside, swallowing whole, regardless of the reception of food and drink plenty of liquids. If it is necessary to reduce the dose, cancel 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 divided into three doses; if necessary, the dose is gradually increased to a maximum of 3600 mg / day. Treatment can begin immediately with a dose of 900 mg / day (300 mg 3 times per day) or within 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 per day;
Day 2: 300 mg 2 times a day;
Day 3: 300 mg 3 times a day.
Partial cramps
Adults and children from 12 years: effective dose - from 900 to 2,400 mg / day. Therapy can begin with a dose of 300 mg 3 times a day. on the first day or increase gradually to 900 mg according to the scheme described above. Subsequently, the dose can be increased to a maximum of 3600 mg / day (divided into 3 equal receptions). The maximum interval between doses with a triple take of the drug should not exceed 12 hours in order to avoid the resumption of seizures.
Selection of a dose for renal failure
Patients with renal failure are recommended to reduce the dose of gabapentin according to the table:
Creatinine clearance Daily dose (mg / sug)
> 80 900-2400
50-79 600-1200
30-49 300-600
15-29 150 * -300
<15 150 *
* appoint 300 mg every other day
Recommendations for patients on hemodialysis
Patients on hemodialysis who had not previously taken gabapentin are recommended to prescribe the drug at a saturating dose of 300-400 mg, and then apply it to 200-300 mg every 4 hours of hemodialysis.
SIDE EFFECT
In the treatment of neuropathic pain
Organism as a whole: accidental injuries, asthenia, back pain, flu-like syndrome, headache, infection, pain of different localization, peripheral edema, weight gain;
Digestive tract: constipation, diarrhea, dry mouth, indigestion, flatulence, nausea, vomiting, abdominal pain;
Nervous system: gait disturbance, amnesia, ataxia, confusion, dizziness, hypoesthesia, drowsiness, disturbance of thinking, tremor;
Respiratory system: dyspnea, pharyngitis;
Skin and subcutaneous tissue: skin rash;
Sense organs: amblyopia.
When treating partial seizures
Organism as a whole: back pain, fatigue, fever, headache, viral infection, peripheral edema, weight gain, asthenia, - general malaise, swelling of the face;
Cardiovascular system: symptoms of vasodilation or hypertension;
Digestive tract: constipation, dental diseases, diarrhea, dyspepsia, increased appetite, dry mouth or throat, nausea and / or vomiting, abdominal pain, flatulence, anorexia, gingivitis;
System of blood, lymphatic system: leukopenia, purpura (most often it was described as bruising that occurred with physical trauma);
Kostno-mische system: fractures, myalgia, arthralgia;
Nervous system: amnesia, ataxia, confusion, coordination disorder, depression, dysarthria, emotional lability, insomnia, nervousness, nystagmus, drowsiness, disturbance of thinking, tremor, muscle twitching, dizziness, hyperkinesia; strengthening, weakening or lack of reflexes, paresthesia, anxiety, hostility;
Respiratory system: cough, pharyngitis, rhinitis, pneumonia;
Skin and subcutaneous tissues: abrasions, a window, skin itching, skin rash;
Sense organs: amblyopia, diplopia, impaired vision;
Genitourinary system: urinary tract infection, impotence.
CONTRAINDICATIONS
- hypersensitivity to any of the components of the drug,
- age up to 12 years with partial seizures.
With caution: kidney failure.
PREGNANCY AND LACTATION
There are no data on the use of the drug in pregnant women, so gabapentin should be used during pregnancy only if the intended benefit to the mother justifies the possible risk to the fetus.
Gabapentin is excreted in breast milk, its influence on the infant is unknown, so during treatment should abandon breastfeeding.
APPLICATION FOR FUNCTIONS OF THE LIVER
Use with caution in renal failure.
In patients with impaired renal function and patients receiving hemodialysis treatment, dose adjustment is recommended.
APPLICATION FOR CHILDREN
Contraindicated at the age of 12 years with partial seizures. To treat neuropathic pain, do not prescribe children and adolescents younger than 18 years old.
SPECIAL INSTRUCTIONS
Although withdrawal syndrome with the development of seizures in the treatment of gabapentin is not noted, nevertheless, a sharp cessation of therapy with antiepileptic drugs in patients with partial seizures can provoke the development of convulsions.
GABAPENTIN is not considered an effective treatment for absence-epilepsy.
Patients who require co-therapy with morphine may require an increase in the dose of gabapentin. In this case, it is necessary to ensure close monitoring of patients for the development of such a sign of central nervous system (CNS) depression as drowsiness. In this case, the dose of gabapentin or morphine should be adequately reduced.
Laboratory research
When Gabapentin was added to other anticonvulsants, false-positive results were detected when determining the protein in the urine using Ames N-Multistix SGВ® test strips. To determine the protein in the urine it is recommended to use a more specific method of precipitation with sulfosalicylic acid. Patients should avoid driving, as well as performing work requiring quickness of psychomotor reactions.
OVERDOSE
Symptoms: dizziness, double vision, speech disturbance, drowsiness, lethargy, diarrhea.
Treatment: gastric lavage, taking activated charcoal, symptomatic therapy. Patients with severe renal insufficiency can be shown hemodialysis.
DRUG INTERACTION
Morphine : with the joint administration of gabapentin and morphine, when morphine was taken 2 hours before admission Gabapentin increased the average area under the pharmacokinetic AUC of gabapentin by 44% compared to gabapentin alone, which was associated with an increase in the pain threshold (a cold pressor test). The clinical significance of this change has not been established, the pharmacokinetic characteristics of morphine remain unchanged. The side effects of morphine when taken together with gabapentin did not differ from those when taking morphine together with placebo. Interactions between gabapentin and phenobarbital, phenytoin, valproic acid and carbamazepine have not been observed. The pharmacokinetics of gabapentin in an equilibrium state is the same in healthy people and patients receiving other anticonvulsants.
The simultaneous use of gabapentin with oral contraceptives containing norethisterone and / or ethinylestradiol was not accompanied by changes in the pharmacokinetics of both components.
The simultaneous use of gabapentin with antacids containing aluminum and magnesium is accompanied by a decrease in the bioavailability of gabapentin by approximately 20%. It is recommended to take gabapentin approximately 2 hours after taking an antacid.
Probenecid does not affect the renal excretion of gabapentin.
A slight decrease in gabapentin's renal excretion with concurrent administration of cimetidine is probably of no clinical significance.
TERMS OF RELEASE FROM PHARMACY
The drug is released by prescription.
TERMS AND CONDITIONS OF STORAGE
The preparation should be stored in a dry, dark place at a temperature of no more than 25 В° C. Keep out of the reach of children.
Shelf life - 2 years. Do not use at the end of the expiration date.
