Description
Co-Trimoxazole Pharmacodynamics
Combined antimicrobial drug consisting of sulfamethoxazole and trimethoprim. Sulfamethoxazole, which is similar in structure to para-aminobenzoic acid, disrupts the synthesis of dihydrofolic acid in bacterial cells by preventing the incorporation of para-aminobenzoic acid into its molecule. Trimethoprim enhances the effect of sulfamethoxazole by disrupting the reduction of dihydrofolic acid into tetrahydrofolic acid, the active form of folic acid responsible for protein metabolism and microbial cell division.
It is a broad spectrum bactericide active against the following microorganisms: Streptococcus spp. (hemolytic strains are more sensitive to penicillin), Staphylococcus spp, Streptococcus pneumoniae, Neisseria meningitidis, Neisseria gonorrhoeae, Escherichia coli (including enterotoxigenic strains), Salmonella spp. (including Salmonella typhi and Salmonella paratyphi), Vibrio cholerae, Bacillus anthracis, Haemophilus influenzae (including ampicillin resistant strains), Listeria spp, Nocardia asteroides, Bordetella pertussis, Enterococcus faecalis, Klebsiella spp., Proteus spp., Pasteurella spp., Francisella tularensis, Brucella spp, Mycobacterium spp. (including Mycobacterium leprae), Citrobacter, Enterobacter spp., Legionella pneumophila, Providencia, some Pseudomonas species (except Pseudomonas aeruginosa), Serratia marcescens, Shigella spp, Yersinia spp., Morganella spp., Pneumocystis carinii; Chlamydia spp. (including Chlamydia trachomatis, Chlamydia psittaci); protozoa: Plasmodium spp., Toxoplasma gondii, pathogenic fungi, Actinomyces israelii, Coccidioides immitis, Histoplasma capsulatum, Leishmania spp.
Resistant to the drug: Corynebacterium spp., Pseudomonas aeruginosa, Mycobacterium tuberculosis, Treponema spp., Leptospira spp. and viruses.
Inhibits the activity of E. coli, which leads to a decrease in the synthesis of thiamine, riboflavin, nicotinic acid and other B vitamins in the intestine. Duration of therapeutic effect is 7 hours.
Indications
– Infections of the urogenital organs: urethritis, cystitis, pyelitis, pyelonephritis, prostatitis, epididymitis, gonorrhea, soft chancre, venereal lymphogranuloma, inguinal granuloma;
– Respiratory infections: bronchitis (acute and chronic), bronchiectatic disease, lumpy pneumonia, bronchopneumonia, pneumocystis pneumonia;
– ENT-organ infections: otitis media, sinusitis, laryngitis, angina; scarlet fever; gastrointestinal infections: typhoid, paratyphoid, salmonellosis, cholera, dysentery, cholecystitis, cholangitis, gastroenteritis caused by enterotoxic strains of Escherichia coli;
– Skin and soft tissue infections: acne, furunculosis, pyoderma, wound infections;
– osteomyelitis (acute and chronic) and other osteoarticular infections, brucellosis (acute), South American blastomycosis, malaria (Plasmodium falciparum), toxoplasmosis (in the complex therapy).
Contraindications
Hypersensitivity to co-trimoxazole, trimethoprim, sulfonamides or to any drug component, pregnancy, breast-feeding, children under 6 years of age (for this dosage form), diagnosed liver parenchyma damage, severe renal insufficiency if it is not possible to determine the drug concentration in plasma (creatinine clearance less than 15 ml/min is not recommended), severe hematologic diseases (aplastic anemia, B12-deficiency anemia, agranulocytosis, leukopenia, megaloblastic anemia, hyperbilirubinemia in children associated with folic acid deficiency), glucose-6-phosphate dehydrogenase deficiency (possibility of hemolysis); concomitant use with dofetilide, paclitaxel and amiodarone; concomitant use with clozapine should be avoided since the latter is known to cause aganulocytosis.
Caution
Folic acid deficiency, bronchial asthma, thyroid disorders.
Usage during pregnancy and lactation
Due to the fact that the safety of the use of co-trimoxazole in pregnant women has not been established, the use of the drug in pregnancy is contraindicated.
It is known that trimethoprim and sulfamethoxazole penetrate into breast milk, therefore, if it is necessary to apply the drug during breast-feeding one should decide on withdrawal of breast-feeding.
Directions for use and dosages
- The drug is taken during or after meals. It is recommended to wash down with alkaline fluids (milk, mineral water).
- Dosing regimen is individual, depending on the severity of the disease, sensitivity and type of pathogen, the age of the patient.
- Children 6 to 12 years: 1 tablet (480 mg) 2 times a day.
- Adults and children over 12 years old take 2 tablets (960 mg) once or 1 tablet (480 mg) 2 times a day. In severe infections 1 tablet (480 mg) 3 times a day, in chronic infections the maintenance dose is 1 tablet (480 mg) 2 times a day.
- In case of uncomplicated infections, 1 tablet two times daily is prescribed for adults over 12 years of age and adults.
- Duration of treatment course is from 5 to 14 days. With a severe course and/or chronic infectious diseases it is allowed to increase the single dose by 30-50%.
