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Bactrim
Last reviewed: 03.07.2025
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Bactrim is one of the antimicrobial drugs with a bactericidal effect. Thus, the drug causes the death of pathogens of various infectious diseases. Moreover, it is able to get rid of even those phenomena that have increased resistance to sulfonamides. When taking Bactrim orally, it is quickly absorbed, the effect of its action lasts about 13 hours. Therefore, it is not worth using the drug often. This can provoke an increase in the dose of the drug in the blood by two times.
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Indications Bactrim
The main indications for the use of Bactrim are the treatment of any infectious diseases of the respiratory tract. The medicine can cope with bronchitis, purulent pleurisy, lung abscess, pneumonia and other phenomena. The drug is widely used for infectious diseases of the genitourinary tract. Thus, it fights cystitis, pyelonephritis, urethritis and other phenomena.
If you need treatment of the gastrointestinal tract, or more precisely the elimination of infections located there, you should take this medicine. It eliminates dysentery, typhoid fever, enterocolitis and other diseases.
The drug is also used for surgical infections, meningitis, gonorrhea, infected wounds and other conditions caused by pathogens sensitive to the drug.
Bactrim is used only with the consent of a doctor. In some cases, this medication alone is enough for a complete recovery. It is worth noting that the sensitivity of bacteria to this drug depends on the area where the person is. This indicator is one of the most important. After all, if you do not take it into account, you may not get relief from using the medication. All this requires a doctor's consultation. Only he can allow the use of Bactrim and prescribe the necessary dose.
Release form
Perhaps, this is not the only medicine that has such an "extensive" form of release. So, Bactrim is a combination medicine, it contains many active components. Among them are sulfamethoxazole and trimethoprim. The ratio of these substances is 5:1.
The product is available in various dosage forms. These may be tablets for adults with a high content of sulfamethoxazole (0.4 g) and trimethoprim (0.08 g). One package contains 20 tablets.
There is also a dosage form for children. Naturally, the content of active substances here is much lower. Thus, one tablet contains 0.1 g of sulfamethoxazole and 0.02 g of trimethoprim. The package contains 20 tablets.
The medicine can also be found in the form of a suspension in syrup, which is located in 100 ml boxes. Thus, the package contains 20 small ampoules of 5 ml. One teaspoon of the medicine contains 0.2 g of sulfamethoxazole and 0.04 g of trimethoprim. There is a suspension in a smaller package, 50 ml. The attending physician decides what form to take Bactrim in.
Pharmacodynamics
Pharmacodynamics of Bactrim shows that it contains two active components: sulfamethoxazole and trimethoprim. The drug has a powerful bactericidal effect on streptococci, gonococci, staphylococci, whooping cough bacilli, chlamydia and other bacteria.
Coryneform bacteria, the causative agent of tuberculosis, and viruses exhibit increased resistance to the drug. The effect of the drug lasts for 7 hours. Sulfamethoxazole is similar in composition to PABA. It is capable of disrupting synthesis with dihydrofolic acid and preventing the inclusion of PABA in its molecule.
Trimethaprim, in turn, significantly enhances the action of the first component. Thus, the restoration of dihydrofolic acid into tetrahydrofolic acid is disrupted. The latter form is responsible for protein metabolism and division of the microbial cell.
Bactrim is a broad-spectrum drug. It is active against many bacteria. The drug significantly inhibits the activity of E. coli. This leads to a decrease in the synthesis of thymine, nicotinic acid and other vitamins in the human intestine.
Pharmacokinetics
The pharmacokinetics of Bactrim are quite unique. Absorption occurs quickly and almost completely. The medicine penetrates into the upper gastrointestinal tract. If the intake was single, then 1.5-3 mg/l of the drug appears in the blood plasma. When a person takes this drug systematically, its concentration in the blood reaches 1.3-2.8 mg/ml.
The distribution of TMP is approximately 130 ml, and that of SMZ is about 20 ml. The latter phenomenon is associated with plasma proteins. The fact is that TMP is several times better than SMZ. It is able to penetrate into non-inflamed prostate tissue, vaginal secretion, healthy and inflamed tissue, saliva, seminal fluid, etc. If we talk about cerebrospinal fluid, both components penetrate here equally.
A large number of TPMs enter the body fluids from the bloodstream. It is worth considering the fact that their concentration significantly exceeds the minimum inhibitory concentrations for most pathogenic microorganisms.
In humans, TMP and SMZ can be found in the placenta, amniotic fluid, and fetal tissue. This suggests that the two components are quite capable of penetrating the placental barrier. Both substances are also excreted in breast milk.
Almost 70% of the received dose of TMP is excreted unchanged. SMS is metabolized in the liver. The period during which the component is completely excreted from the body is 10 hours. Elderly people with liver problems have their own characteristics. They require adjustment of the dose of Bactrim, because the half-life is much longer.
Dosing and administration
Such an important point as the method of application and dosage of Bactrim is decided by the attending physician. The instructions may indicate anything. Simply put, this is how standard options for administration are written. But it is worth considering the individual characteristics of the body, the person's condition, and his or her tolerance of certain components. All this suggests that the dose should be adjusted individually for each case.
The daily dosage of the drug should not exceed 4 tablets. If we are talking about syrup, then no more than 8 spoons. The suspension is often given to children under 12 years old, so it is absorbed faster and provides quick relief. True, the dosage is somewhat different. The child should take half a measuring spoon twice a day. But this applies only to newborn babies up to 5 months. Starting from five years, the dosage increases to two measuring spoons twice a day.
The course of treatment with the drug is from 5 days to 2 weeks. But all this is strictly individual. Much depends on the infection itself and the person's condition. If the problem is chronic, the duration of treatment is much longer. The dose of Bactrim can also be adjusted.
Use Bactrim during pregnancy
Is it possible to use Bactrim during pregnancy? Experiments that were conducted on animals indicate that large doses of the drug can lead to fetal malformations. This is a typical condition in the case of folic acid deficiency.
According to the survey, there were no individual reports of fetal malformations in women. Taking the drug is apparently not associated with a reliable risk of teratogenicity for humans. After all, TMP and SMZ are able to penetrate the placental barrier. Thus, they can affect the metabolism of folic acid that occurs during pregnancy.
The drug is prescribed only in cases where the expected benefit from its use can outweigh the risk to the fetus. Pregnant women who are recommended to take this drug are prescribed 5-10 mg of folic acid additionally.
It is prohibited to use the product in the later stages. There is a risk of developing nuclear jaundice in newborns. TMP and SMZ can penetrate into breast milk. Therefore, during the period of breastfeeding, the product should not be taken under any circumstances. Bactrim can only be used with the permission of a doctor.
Contraindications
Individual intolerance to the drug component, kidney disease and other problems are the very contraindications to the use of Bactrim. Many people suffer from a special intolerance to sulfanamide drugs. It is also not recommended to use the drug in case of kidney, liver and circulatory system diseases.
Pregnant women should not use the medicine, as it may negatively affect the development of the fetus and lead to problems in the future. Premature and newborn babies are also at risk. The medicine is used with special caution by young children.
The drug should not be used together with novocaine, folic acid, anesthesin, furadonin and other substances. Diuretics are also incompatible with this medicine. Acids can increase the risk of complications.
All this suggests that the drug can only be used with the permission of a doctor. Bactrim has a strong effect on the body and can worsen the situation.
Side effects Bactrim
Depending on the individual characteristics of the body, side effects of Bactrim may develop. The urinary system manifests itself first. Nephritis may develop, an increase in the concentration of urea, polyuria, crystalluria and other phenomena will appear.
From the respiratory system, these are bronchospasms, dizziness, and headache. The musculoskeletal system also manifests itself in the form of arthralgia and myalgia. In some cases, depression, meningitis, neuritis, apathy, and tremor may develop. From the digestive system, abdominal pain, gastritis, loss of appetite, nausea, vomiting, diarrhea, hepatitis, and other phenomena are observed.
The development of hypoglycemia and allergic reactions is not excluded. Moreover, the latter phenomenon can have varying degrees of severity. There are quite a few side effects, but if you take the drug exactly as prescribed by the doctor, then there is nothing to worry about. Only the presence of certain problems and an independent increase in the dose can lead to the development of undesirable effects. Therefore, Bactrim should be taken under supervision.
Overdose
If the drug is taken incorrectly, then an overdose of Bactrim is possible. The main symptoms of this phenomenon are nausea, vomiting, headache and drowsiness. In some cases, depression may develop. Fainting, confusion, visual impairment and fever are also among the main symptoms of an overdose of the drug.
More serious phenomena may also occur. These include thrombocytopenia, megaloblastic anemia, and jaundice. This occurs with prolonged overdose. Simply put, if the dose was constantly increased on its own and the body did not react to it in any way.
Getting rid of simple unpleasant phenomena is not so difficult. It is enough to simply wash the stomach. It is necessary to acidify the urine, this can provoke rapid excretion of trimethoprim. To do this, you need to drink the appropriate liquid. If necessary, hemodialysis is performed.
All the above-described troubles can develop as a result of an independent increase in the dose or intolerance to some components of the drug. Therefore, Bactrim is used under the supervision of a doctor.
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Interactions with other drugs
This medication has interactions with other drugs, but this is done with extreme caution. Pharmaceutically, the drug is compatible with levulose, sodium chloride, dextran, dextrose and Ringer's solution.
The drug is capable of increasing the anticoagulant activity of indirect anticoagulants. In addition, it increases the effect of hypoglycemic drugs and methotrexate. The intensity of hepatic metabolism of phenytoin and warfarin is significantly reduced. Their overall effect is enhanced.
Reliability of oral contraception may decrease. This occurs because the drug suppresses intestinal microflora and reduces enterohepatic circulation of hormonal compounds.
If the drug is taken together with pyrimethamine in high doses, it can provoke the development of megaloblastic anemia. Diuretics can increase the risk of thrombocytopenia. The effect of procaine, procainamide and benzocaine is significantly reduced. Phenytoin can provoke the manifestation of folic acid deficiency.
Salicylic acid derivatives can enhance the effect of the drug. Cholestyramine reduces absorption, so it is recommended to take it an hour after co-trimoxazole. When using Bactrim, it is worth considering all of the above and consulting a doctor.
Storage conditions
What do the storage conditions of Bactrim depend on? In this case, the temperature regime plays a big role. So, it should not exceed the mark of 30 degrees Celsius. It is not recommended to freeze the product, but if there is such a need, then after the defrosting process it should be used immediately.
In addition to the temperature regime, the storage location also plays an important role. It must be protected from direct sunlight. It is also important that there is no dampness there. A dry, warm and dark place is a great way to preserve the positive properties of the medicine for a long time.
It is necessary to protect the drug from children's attention. After all, they can break the bottle, get hurt or drink its contents. All this can lead to serious health problems. It is advisable to monitor the appearance of the tablets and suspension. If they change color, then most likely the storage conditions were not observed correctly. It is not recommended to take such a drug. Only the right conditions can preserve all the beneficial properties of the drug Bactrim.
Shelf life
The expiration date is another important indicator. So, basically, many drugs have a long period of use. Bactrim can be stored for 5 years.
But a long shelf life in many cases turns out to be negligible. In order for the drug to last exactly as long as indicated on the package, you will have to create all the necessary conditions. For example, you need to exclude direct sunlight and remove dampness. These two negative indicators can reduce the shelf life of the drug several times.
It is also worth observing the appearance of the tablets. The blister they are in should not be damaged. The color of the syrup does not change over time. If this happens, it is prohibited to use it. This can lead to serious problems.
You also need to watch the packaging itself. The slightest damage can reduce the shelf life of the drug. In order not to harm children and keep the medicine for a long time, you will have to put it away. Children should not have access to the drug. Compliance with all these conditions guarantees that Bactrim will last all 5 years.
Attention!
To simplify the perception of information, this instruction for use of the drug "Bactrim" translated and presented in a special form on the basis of the official instructions for medical use of the drug. Before use read the annotation that came directly to medicines.
Description provided for informational purposes and is not a guide to self-healing. The need for this drug, the purpose of the treatment regimen, methods and dose of the drug is determined solely by the attending physician. Self-medication is dangerous for your health.