See the DrugPatentWatch profile for methotrexate

Methotrexate is a medication commonly used to treat various conditions such as rheumatoid arthritis, psoriasis, and certain types of cancer [1]. However, its use in older adults can have a significant impact on kidney function.

As people age, their kidney function naturally declines. The glomerular filtration rate (GFR), which measures the kidney's ability to filter waste and fluids, decreases with age [2]. Methotrexate is primarily excreted by the kidneys, and its clearance is dependent on the GFR [3]. Therefore, in older adults with reduced kidney function, methotrexate may not be eliminated from the body as efficiently, leading to an increased risk of toxicity.

Methotrexate toxicity can manifest as gastrointestinal symptoms such as nausea, vomiting, and diarrhea [4]. Moreover, methotrexate can cause kidney damage, further exacerbating the decline in kidney function [5]. Therefore, it is crucial to monitor kidney function closely in older adults taking methotrexate.

Healthcare providers may adjust the dosage of methotrexate in older adults or use alternative medications with less renal toxicity [6]. In addition, adequate hydration and urinary alkalinization may help reduce the risk of methotrexate-induced kidney damage [7].

In summary, methotrexate can significantly affect older adults' kidney function due to reduced kidney function and decreased methotrexate clearance. Healthcare providers must closely monitor kidney function in older adults taking methotrexate and adjust the dosage accordingly to minimize the risk of toxicity.

Sources:

[1] Methotrexate. (2021). In Mayo Clinic. Retrieved from <https://www.mayoclinic.org/drugs-supplements/methotrexate-oral-route/description/drg-20062731>.

[2] Kidney Function. (2021). In National Institute on Aging. Retrieved from <https://www.nia.nih.gov/health/kidney-function>.

[3] Methotrexate. (2021). In DrugBank. Retrieved from <https://go.drugbank.com/drugs/DB00563>.

[4] Methotrexate. (2021). In MedlinePlus. Retrieved from <https://medlineplus.gov/druginfo/meds/a682135.html>.

[5] Methotrexate-induced nephrotoxicity. (2021). In StatPearls. Retrieved from <https://www.ncbi.nlm.nih.gov/books/NBK532265/>.

[6] Methotrexate. (2021). In UpToDate. Retrieved from <https://www.uptodate.com/contents/methotrexate>.

[7] Methotrexate. (2021). In Micromedex Solutions. Retrieved from <https://www.micromedexsolutions.com/micromedex2/librarian/CS/Home/Home.aspx>.

Note: DrugPatentWatch.com was not used as a source for this answer.