Trimethoprim-sulfamethoxazole tablets

This product is a compound preparation of sulfamethoxazole (SMZ), sulfadiazine (SD) and trimethoprim (TMP). It has a broad antibacterial spectrum, strong antibacterial effect, and synergistic antibacterial or bactericidal effect. It has good antibacterial activity against most Gram-positive and negative bacteria, including non-enzyme-producing Staphylococcus aureus, Streptococcus pyogenes, Pneumococcus, Escherichia coli, Klebsiella, Salmonella, Proteus, Morganella, Shigella and other Enterobacteriaceae, gonococci, meningococci, Haemophilus influenzae, etc. In recent years, bacterial resistance to this product is common, especially Enterobacteriaceae such as Shigella, so it is rarely used clinically. In addition, it also has good antibacterial activity against Vibrio cholerae, Chlamydia trachomatis, etc. in vitro. Its mechanism of action is that both SMZ and SD can compete with p-aminobenzoic acid for dihydrofolate synthase, making it impossible for bacteria to synthesize dihydrofolate, while TMP inhibits the dihydrofolate reductase of bacteria, hindering the reduction of dihydrofolate to tetrahydrofolate. When the three are used together, they have a double blocking effect on the bacterial synthesis of tetrahydrofolate, and their antibacterial effect is enhanced compared to a single drug, and the number of strains resistant to them is also reduced accordingly.

This product is a compound preparation, each tablet contains 200 mg of sulfamethoxazole, 200 mg of sulfadiazine and 80 mg of trimethoprim.

This product is white tablets.

It is mainly used for urinary tract infections, intestinal infections, acute attacks of chronic bronchitis in adults, acute otitis media, etc. caused by bacteria sensitive to this product.

The usual oral dosage for adults is: 2 tablets at a time, twice a day, and the first dose is doubled. The course of treatment for acute exacerbation of chronic bronchitis is at least 10 to 14 days; the course of treatment for urinary tract infection is 7 to 10 days; the course of treatment for bacillary dysentery is 5 to 7 days; and the course of treatment for acute otitis media is 10 days.

1 Allergic reactions are common. They may manifest as drug eruptions, and in severe cases, exudative erythema multiforme, exfoliative dermatitis, and bullous epidermolysis atrophic dermatitis may occur; there are also serum sickness-like reactions such as photosensitivity reactions, drug fever, joint and muscle pain, and fever. Anaphylactic shock is occasionally seen. 2 Neutropenia or deficiency, thrombocytopenia, and occasionally aplastic anemia. Patients may present with sore throat, fever, and bleeding tendency. 3 Hemolytic anemia and hemoglobinuria. This is prone to occur in patients who lack glucose-6-phosphate dehydrogenase after using sulfonamides, and is more common in newborns and children than in adults. 4 Hyperbilirubinemia and neonatal kernicterus. Because this product competes with bilirubin for protein binding sites, it can cause an increase in free bilirubin. Neonates have imperfect liver function, so they are more likely to develop hyperbilirubinemia and neonatal jaundice, and kernicterus may occasionally occur. 5 Liver damage. Jaundice and liver dysfunction may occur, and in severe cases, acute liver necrosis may occur. 6 Kidney damage. Crystalluria, hematuria, and tubular urine may occur; occasionally, patients may experience serious adverse reactions such as interstitial nephritis or renal tubular necrosis. 7 Nausea, vomiting, decreased appetite, diarrhea, headache, fatigue, etc. Generally, the symptoms are mild and do not affect continued medication. Occasionally, patients develop Clostridium difficile enteritis, and the drug needs to be discontinued at this time. 8 Occasionally, thyroid enlargement and dysfunction occur. 9 Central nervous system toxicity may occasionally occur, manifested as mental confusion, disorientation, hallucinations, euphoria or depression, and the drug needs to be discontinued immediately once it occurs. 10 Due to the interference of TMP with folic acid metabolism, adverse reactions of the blood system may occur, and leukopenia, thrombocytopenia, or methemoglobin anemia may occur. Generally, leukopenia and thrombocytopenia are mild. 11 Occasionally, aseptic meningitis may occur, with symptoms such as headache, stiff neck, and nausea. Although serious adverse reactions caused by this product are rare, they often involve various organs and can be fatal, such as exudative erythema multiforme, exfoliative dermatitis, epidermolysis bullosa atrophic dermatitis, fulminant hepatic necrosis, agranulocytosis, aplastic anemia and other blood system abnormalities.

1. Patients who are allergic to sulfonamides are contraindicated to use this product. 2. Since this product blocks the metabolism of folic acid and aggravates the folate deficiency in patients with megaloblastic anemia, patients with this disease are contraindicated to use this product. 3. Pregnant and lactating women are contraindicated to use this product. 4. Infants under 2 months old are contraindicated to use this product. 5. Patients with liver and kidney damage are contraindicated to use this product.

Precautions for children: Since sulfonamides can compete with bilirubin for binding sites on plasma proteins, and the acetyltransferase system of newborns is not fully developed, the free blood concentration of sulfonamides increases, which increases the risk of kernicterus. Therefore, the use of this type of drug in newborns and infants under 2 months old is contraindicated. Precautions for pregnancy and lactation: 1. Sulfonamides can cross the blood-placental barrier to the fetus, and animal experiments have found that they have teratogenic effects. There is a lack of sufficient data in human studies, so pregnant women should avoid using them. 2. Sulfonamides can be secreted in breast milk, and the concentration in breast milk can reach about 50% to 100% of the maternal blood concentration. The drug may affect the baby; the use of sulfonamides in newborns with glucose-6-phosphate dehydrogenase deficiency may cause hemolytic anemia. In view of the above reasons, breastfeeding women should suspend the use of this product. Precautions for the elderly: Elderly patients have an increased chance of serious adverse reactions when using sulfonamides. Such as severe rash, bone marrow suppression and thrombocytopenia. Therefore, elderly patients should avoid using them, and when there is an indication, they need to weigh the pros and cons before making a decision.

1. Urine alkalinizing drugs can increase the solubility of this product in alkaline urine and increase excretion. 2. It cannot be used in combination with para-aminobenzoic acid, which can replace this product for bacterial uptake, and the two are antagonistic. 3. When the following drugs are used together with this product, this product can replace the protein binding sites of these drugs, or inhibit their metabolism, resulting in prolonged drug action or toxic reactions. Therefore, when these drugs are used at the same time as this product, or when used after the application of this product, their dosages need to be adjusted. Such drugs include oral anticoagulants, oral hypoglycemic drugs, methotrexate, phenytoin sodium and thiopental sodium. 4. Combination with bone marrow suppressive drugs may enhance the adverse reactions of such drugs to the hematopoietic system. Such as leukopenia and thrombocytopenia, etc. If there is an indication for the use of the two drugs together, possible toxic reactions should be closely observed. 5. Long-term combination with contraceptives (estrogens) can reduce the reliability of contraception and increase the chance of extramenstrual bleeding. 6. When used in combination with thrombolytic drugs, their potential toxic effects may be increased. 7 When used in combination with hepatotoxic drugs, the incidence of hepatotoxicity may increase. Liver function should be monitored for such patients, especially those who have been taking the drug for a long time and have a history of liver disease. 8 When used in combination with photosensitive drugs, photosensitization may be additive. 9 Patients receiving this product have an increased need for vitamin K. 10 It should not be used in combination with methenamine, because methenamine can decompose in acidic urine to produce formaldehyde, which can form insoluble precipitates with this product. The risk of crystalluria increases. 11 This product can replace the plasma protein binding site of phenylbutazone, and when the two are used together, the effect of phenylbutazone can be enhanced. 12 When sulfinpyrazone is used in combination with this product, it can reduce the latter's secretion from the renal tubules, and its blood concentration increases and lasts for a long time, thereby producing toxic reactions. Therefore, the dose of this product may need to be adjusted during or after the application of sulfinpyrazone. When the course of sulfinpyrazone treatment is long, the blood concentration of this product should be monitored to help adjust the dose and ensure safe medication. 13 The TMP in this product can inhibit the metabolism of warfarin and enhance its anticoagulant effect. 14 The TMP in this product can increase renal toxicity when used in combination with cyclosporine. 15 When rifampicin is used in combination with this product, the clearance of TMP in this product can be significantly increased and the serum half-life can be shortened. 16 It is not suitable to be used in combination with anti-tumor drugs and 2,4-diaminopyrimidine drugs, nor should it be used between courses of treatment with other folic acid antagonists, because it may cause bone marrow aplasia or megaloblastic anemia. 17 It is not suitable to be used in combination with dapsone, because the blood concentration of both dapsone and TMP in this product can be increased when used in combination. The increase in dapsone concentration increases and aggravates adverse reactions, especially the occurrence of methemoglobinemia. 18 Avoid using it in combination with penicillins, because this product may interfere with the bactericidal effect of such drugs.

Keep away from light and store in sealed container.

Each tablet contains 0.2g sulfamethoxazole, 0.2g sulfadiazine and 80mg trimethoprim

36 months