Methotrexate is a medication commonly used to treat various conditions, such as rheumatoid arthritis, psoriasis, and certain types of cancer [1]. Its impact on other medications' effectiveness can depend on several factors, including the type of medication, dosage, and individual patient characteristics.

One potential interaction of methotrexate is with drugs that decrease its elimination from the body, leading to increased methotrexate levels and potentially increased toxicity [1]. For example, some medications that may increase methotrexate levels include probenecid, certain antibiotics (such as penicillins and tetracyclines), and nonsteroidal anti-inflammatory drugs (NSAIDs) [1].

On the other hand, methotrexate may also affect the effectiveness of other medications. For instance, methotrexate can reduce the efficacy of certain vaccines, such as live attenuated vaccines [1]. Additionally, methotrexate may increase the risk of adverse effects associated with nondepolarizing muscle relaxants during anesthesia [1].

It is essential to consult a healthcare professional or pharmacist for personalized advice on potential drug interactions when taking methotrexate or any other medication. They can provide guidance based on an individual's medical history and current medications.

In summary, methotrexate can impact the effectiveness of other medications and be affected by concomitant drug administration. Regular communication with healthcare professionals is crucial to ensure safe and effective treatment.

Sources:

1. U.S. National Library of Medicine. (2021). Methotrexate. MedlinePlus. Retrieved from <https://medlineplus.gov/druginfo/meds/a68/130564.html>
2. DrugPatentWatch.com. (n.d.). Methotrexate. Retrieved from <https://www.drugpatentwatch.com/drugs/methotrexate>