Mechanism of action
Combined antibacterial drug, the action of which is due to the properties of the components included in its composition. Sulfamethoxazole has a bacteriostatic effect, which is associated with inhibition of the utilization of PABA and impaired synthesis of dihydrofolic acid in bacterial cells. Trimethoprim inhibits an enzyme that is involved in the metabolism of folic acid, converting dihydrofolate to tetrahydrofolate. Thus, Biseptol blocks 2 successive stages of the biosynthesis of purines and, therefore, nucleic acids, which are necessary for the growth and reproduction of bacteria.
Active against gram-positive bacteria: Streptococcus spp., Staphylococcus spp., Listeria monocytogenes, Nocardia asteroides; Gram-negative bacteria: Enterobacter spp., Salmonella spp., Shigella spp., Klebsiella spp., Some strains of Escherichia coli, Moraxella catarrhalis, Haemophilus ducreyi, some strains of Haemophilus influenzae, Brucella spp. A drug is also active in relation to Toxoplasma gondii, Pneumocystis carinii.
After taking the drug inside the active substances are quickly and completely absorbed from the gastrointestinal tract.
Cmax in blood plasma is achieved within 2-4 hours after ingestion.
T1/2 - 10-12 h. Both active substances are excreted in the urine.
Indications and usage
Infectious and inflammatory diseases caused by microorganisms sensitive to the drug:
- infections of the urinary system (including acute and chronic urethritis, cystitis, pyelonephritis);
- infections of the middle ear;
- infections of the genital tract (including postgonoreal urethritis, prostatitis, gonorrheal epididymitis, acute and chronic gonorrhea);
- respiratory tract infections (including laryngitis, tonsillitis, acute and chronic bronchitis, bronchiectasis, pneumonia);
- pneumonia caused by Pneumocystis carinii (including in AIDS patients);
- scarlet fever;
- Meningitis, abscess of the brain;
- gastrointestinal infections (including typhoid fever, paratyphoid fever, bacterial dysentery, cholera / in combination therapy /, acute gastroenteritis, chronic colitis of unknown etiology);
- infections of the skin and soft tissues (including furunculosis, impetigo, erysipelas, purulent folliculitis, abscesses, acne, infected wounds, complicated purulent infection after surgery in the area of the palms and fingers);
- cholecystitis, cholangitis;
- Toxoplasmosis (as part of combination therapy).
Children aged 2 to 5 years the drug is prescribed in 240 mg (2 tablets. 120 mg) 2 times / day; children aged 6 to 12 years - 480 mg each (4 tab. 120 mg or 1 tab. 480 mg) 2 times / day.
At pneumonia the drug is prescribed at the rate of 100 mg of sulfamethoxazole per 1 kg of body weight / day. The interval between doses of 6 hours, the duration of reception - 14 days.
At gonorrhea The dose of the drug is 2 g (in terms of sulfamethoxazole) 2 times / day with an interval between doses of 12 hours.
Adults and children over 12 years old the drug is prescribed on 960 mg 2 times / day, if necessary, long-term therapy - 480 mg 2 times / day.
Duration of a course of treatment from 5 to 14 days. At severe disease and / or chronic infections may increase the single dose of 30-50%.
Tablets are taken after a meal, drinking plenty of liquids.
Gastrointestinal: rarely - nausea, vomiting, diarrhea; in rare cases - pseudomembranous colitis.
Allergic reactions: hives; in isolated cases - Stevens-Johnson syndrome, Lyell's syndrome.
Hemic and lymphatic: in rare cases - reversible thrombocytopenia, leukopenia; megaloblastic anemia (especially with prolonged use in the elderly).
Urogenital: rarely - crystalluria (when used in high doses).
From the side of the central nervous system: in rare cases - headache, depression, dizziness.
Side effects are usually mild and reversible after discontinuation of the drug.
- severe liver dysfunction;
- pronounced impaired renal function (especially if the CC is less than 15 ml / min);
- violations of the hematopoietic system;
- Severe diseases of the cardiovascular system;
- deficiency of glucose-6-phosphate dehydrogenase;
- hypersensitivity to the drug.
The drug is not prescribed to newborns (children under 6 weeks).
Pregnancy and breastfeeding
Biseptol is contraindicated for use in pregnancy.
If necessary, the use of the drug during lactation should decide on the termination of breastfeeding.
The appearance of a skin rash or diarrhea severe course is an indication for discontinuation of the drug.
Control of laboratory parameters
With prolonged use (more than 14 days), especially in elderly patients, it is necessary to monitor the picture of peripheral blood.
With the development of disorders on the part of the peripheral blood picture, the administration of folic acid is indicated (at a dose of 5-10 mg / day).
Symptoms: may increase the described side effects.
With the simultaneous use of Biseptol enhances the effect of indirect anticoagulants, hypoglycemic agents and Methotrexate.
When combined with phenytoin, barbiturates, PAS Biseptol increases the deficiency of folic acid.
With simultaneous use of barbiturates increase the risk of developing the toxic effects of Biseptolum.
With the simultaneous use of salicylic acid compounds enhance the effect of Biseptol.
The drug should be stored in a dry, dark place.