methotrexate vs trimethoprim
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Side-by-side comparison of methotrexate and trimethoprim. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
minor Known Drug Interaction
Sulfonamides can also displace methotrexate from plasma protein binding sites and can compete with the renal transport of methotrexate, thus increasing free methotrexate concentrations.
Trexall, Otrexup
Primsol
Methotrexate is a drug that can treat certain cancers, rheumatoid arthritis, psoriasis, and other conditions. It works by slowing the growth of cells in the body.
This medicine contains sulfamethoxazole and trimethoprim. It is an antibiotic that fights bacteria in your body.
Methotrexate can treat acute lymphoblastic leukemia, a type of cancer, in adults and children. It also treats mycosis fungoides, a skin lymphoma, in adults. Additionally, it treats relapsed or refractory non-Hodgkin lymphoma in adults. For non-cancer conditions, it treats rheumatoid arthritis in adults, polyarticular juvenile idiopathic arthritis (pJIA) in children, and severe psoriasis in adults.
This medicine can treat urinary tract infections, ear infections in children, and bronchitis in adults. It also treats shigellosis, a type of diarrhea. It can also treat or prevent Pneumocystis jiroveci pneumonia, and treat traveler's diarrhea.
Methotrexate blocks an enzyme called dihydrofolate reductase. This enzyme is needed for cells to grow and multiply. By blocking this enzyme, methotrexate slows down the growth of cells, especially cancer cells and cells that cause inflammation in arthritis and psoriasis.
This medicine works by stopping bacteria from making folic acid. Bacteria need folic acid to grow and multiply. By blocking folic acid production, the medicine kills the bacteria.
- • Mouth sores
- • Nausea
- • Abdominal pain
- • Changes in liver tests
- • Nausea
- • Vomiting
- • Loss of appetite
- • Skin rash
- • Hives
- Rheumatoid Arthritis 38,053
- Arthralgia 36,283
- Pain 35,413
- Fatigue 29,061
- Nausea 24,009
- Nausea 945
- Diarrhoea 848
- Headache 835
- Malaise 816
- Pyrexia 721
Methotrexate can cause serious harm to an unborn baby, including death. If you are pregnant, you should not take this medicine for non-cancer conditions. If you are taking it for cancer, talk to your doctor about the risks. This medicine can also cause severe allergic reactions and other serious side effects that can be life-threatening. Contact your doctor immediately if you experience any signs of infection, lung problems, or kidney problems.
Rarely, sulfonamide drugs like this one have caused severe reactions. These include Stevens-Johnson syndrome, toxic epidermal necrolysis, liver damage, and blood problems. Tell your doctor right away if you have a fever, rash, blisters, mouth sores, or signs of infection.
Methotrexate can cause birth defects or fetal death if taken during pregnancy for non-cancer conditions. If you are pregnant or plan to become pregnant, talk to your doctor. Do not breastfeed while taking methotrexate, as it can pass into breast milk and harm your baby.
Tell your doctor if you are pregnant or plan to become pregnant. This medicine may not be safe for your baby. Talk to your doctor about the risks and benefits of taking this medicine while breastfeeding.
Also Compare, Nearby Drugs
Compare methotrexate with
How to Read This methotrexate vs trimethoprim Comparison
methotrexate is classified in the Disease-Modifying Antirheumatic Drug (DMARD) drug class, while trimethoprim sits within the Dihydrofolate Reductase Inhibitor class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, methotrexate has 162,819 submissions while trimethoprim has 4,165. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known minor interaction flagged in FDA labeling, attributed to trimethoprim can push methotrexate off the proteins it normally sticks to in the blood and slow down how fast the kidneys remove it. this leads to higher levels of methotrexate in the body.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.
A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for methotrexate or trimethoprim.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.