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By Medicover Hospitals / 23 Jan 2021
Home | Medicine | Trimethoprim

What is Trimethoprim?

  • Trimethoprim is an antibiotic used specifically in the treatment of infections of the bladder. Other applications include middle ear infections and diarrhea for passengers. It can be used for Pneumocystis pneumonia in individuals with HIV/AIDS with sulfamethoxazole or dapsone. It is swallowed by the mouth.
    1. Trimethoprim Uses
    2. Trimethoprim Side effects
    3. Precautions
    4. Overdose
    5. Trimethoprim Interactions
    6. Interactions Storage
    7. Interactions vs Methotrexate
    8. Frequently Asked Questions
    9. Citations

    Trimethoprim uses:

  • Trimethoprim is an antibiotic used to treat infections caused by bacteria. It works by preventing bacteria from developing. Only bacterial infections are treated by this antibiotic. For viral infections, it will not work (such as common cold, flu). Using any antibiotic will cause it not to function for future infections when it is not needed.
  • How to take Trimethoprim?

  • Take this medicine by mouth, as prescribed by your doctor, with or without food, usually once or twice a day. The dosage is completely dependent on your medical condition and your treatment reaction. In kids, the dosage is dependent on their weight as well.
  • Carefully calculate/evaluate the dosage using a special measurement device or spoon if you are using the liquid form of this drug. Never use a household spoon, since the correct dosage can not be given to you by using a household spoon.
  • Take this antibiotic at a uniformly spaced interval of times for the best effect. consume this drug at the same time every day.
  • Continue to take this drug until completion of the maximum amount given, even though symptoms disappear after a couple of days while consuming dosage. Incomplete doses can harm you
  • Trimethoprim Side Effects:

  • There may be diarrhea, nausea, vomiting, sore stomach, lack of appetite, changes in taste, and headaches. Tell your physician or pharmacist immediately if any of these symptoms are still continuing for a longer period of time after taking this drug.
  • Know that this drug has been prescribed by your doctor because he or she has decided and felt that the value is greater than the risk of side effects. There are no serious/significant side effects for many people who use this drug.
  • Tell your doctor right away if you notice any severe side effects, including new symptoms of infection (such as sore throat that does not go away, fever), quick bruising/bleeding, pale skin, excessive tiredness, fast/irregular heartbeat, mental/mood changes, signs of non-stop liver disease (such as nausea/vomiting, dark urine, stomach/abdominal pain, yellowing of the eyes/skin), stiffness of the neck, headache, or headache.
  • Because of a type of resistant bacteria, this medication can rarely cause a serious intestinal condition (Clostridium difficile-associated diarrhea). This condition can occur during therapy or weeks to months after discontinuation of treatment. If you have some diarrhea that doesn't end, abdominal or stomach pain/cramping, blood/mucus in your feces, tell your doctor right away
  • If you have any of these symptoms, do not use anti-diarrhea or opioid drugs, because these products can make them worse.
  • For prolonged or repetitive periods, the use of this medication may result in oral thrush or a new infection of the yeast. If you find white patches in your mouth, a shift in vaginal discharge, contact your physician
  • If you have some very uncommon/unpleasant side effects, including seizures, seek medical attention right away.
  • It is very unusual to experience a very serious/severe allergic reaction to this drug. However, if you experience any signs of a serious/rare allergic reaction, including rash, itching, swelling (especially of the face, tongue, throat), dizziness, difficulty breathing, get medical assistance immediately.
  • Precautions:

  • Tell your doctor or pharmacist whether you are allergic to trimethoprim before taking it or whether you have any other allergies. There may be some or many inactive ingredients present in this substance that may cause allergic reactions or other problems and harm you.
  • Tell your doctor or pharmacist your medical history before taking this drug, particularly: certain forms of anemia (due to folate deficiency), kidney disease, liver disease, vitamin (folate or folic acid) deficiency, some blood disorders (such as bone marrow suppression or G6PD deficiency), imbalances (such as high level of potassium or low level of sodium in the blood).
  • You can become more responsive to the sunlight with this medicine. In the heat, limit your time. Avoid booths and sun lamps for tanning. When outside, use sunscreen and protective clothing. If you get exposed to the sun or have skin blisters/redness, ask your doctor immediately.
  • If you have diabetes, your blood sugar might be affected due to the dosage of this medication. As instructed by your doctor, check your blood sugar levels regularly and share the results with your doctor if it gets to change. If you have signs of low blood sugar, tell your doctor immediately Your doctor will need to change your diabetes medicine, exercise regimen, or diet.
  • Trimethoprim can also cause live bacterial vaccines to not function (such as the typhoid vaccine). Do not have any immunizations
  • Older adults may be more prone to the side effects of this medication, especially mineral imbalances (high blood potassium) and allergic reactions.
  • If you are pregnant or want to become pregnant, inform your doctor. When using trimethoprim, you should not become pregnant. An unborn baby can be affected by Trimethoprim. It can lower the levels of folic acid, raising the likelihood of defects in the spinal cord. Check with your doctor to make sure there is enough folic acid you are taking. Speak to the doctor if you get pregnant
  • It moves into breast milk with trimethoprim. Although no findings of harm to breastfeeding babies have been published, consult your doctor before breast-feeding.
  • Interactions:

  • Drug interactions can sometimes change/affect the working of your drugs or increase the risk of serious side effects. Without your doctor's permission, do not start taking, stopping suddenly, or adjust the dosage of any medication. Dofetilide is a substance that may interfere with this drug.
  • Certain lab tests (including kidney function and blood levels of methotrexate) can interfere with this drug, probably causing false test results. Make sure the medical personnel and all the physicians know that you are using this medicine.
  • Note
  • Do not share with anyone this drug. Only for your present condition has this drug been prescribed. Unless your doctor advises you to, do not use it for another infection later on. When you are taking this drug, laboratory and/or medical tests (such as full blood counts, kidney function, potassium blood level, cultures) should be performed.
  • Overdose:

  • Do not consume more than what is prescribed to you. If you or someone has taken an overdose immediately go to see a doctor.
  • Missed Dose:

  • If a dose is missing or you have forgotten, take it as soon as you recall it. If the time for the next dose is already arrived or close, skip the skipped dose. At your normal dosage time, take your next dosage. To catch up, do not double the dosage.
  • Storage:

  • Store this drug in a place that is free from light and moisture at room temperature. Do not dispose of it any place or drains
  • Trimethoprim vs Methotrexate:

    Trimethoprim Methotrexate
    Trimethoprim is an antibiotic It is from a class of medications called antimetabolites.
    Formula: C14H18N4O3 Formula: C20H22N8O5
    Used for treatment of bladder infections used to treat cancer, medical abortions, ectopic pregnancy, and autoimmune diseases
    also known as co-trimoxazole known as amethopterin

    Frequently Asked Questions:

    Trimethoprim can be used for treating uncomplicated urinary tract infections caused by Proteus mirabilis, Escherichia coli, Klebsiella pneumonia, and coagulase-negative Staphylococcus, although it is rarely used alone due to some possible bacterial resistance.
    Trimethoprim is an antibiotic. It's used to treat infections of the urinary tract(UTIs), such as cystitis.
    Trimethoprim belongs to a class of medicine that is an antibacterial antifolate agent that inhibits bacterial dihydrofolate reductase (DHFR), a crucial enzyme that catalyzes tetrahydrofolic acid (THF) formation, preventing the synthesis and ultimately continued survival of bacterial DNA.
    With amoxicillin-clavulanate, gastrointestinal side effects were more frequent (p less than 0.0001). Our findings indicate that trimethoprim-sulfamethoxazole is more clinically beneficial for acute otitis media twice daily and causes fewer side effects than amoxicillin-clavulanate twice daily.
    Your symptoms will normally start improving within 24 to 48 hours of taking Trimethoprim 200mg medication.
    Your doctor or pharmacist will inform you how long you can use trimethoprim (usually 3 to 7 days). Half a tablet (150mg) at night is the dosage to avoid infection. In order to avoid recurring infections, you would need to take trimethoprim every night for a few months if you have chronic urinary infections.
    Yes, taking this drug might have side effects which include feeling dizzy and sleepy.
    We would say that in everyday practice, 3 days of trimethoprim care tends to be as successful as 5 or 7 days, and we would endorse this as the preferred alternative for uncomplicated UTIs in young people. Percentage of infections with 'first'.


  • Trimethoprim,
  • Resistance to Trimethoprim,