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]. The dosage of methotrexate can vary depending on several factors, including the patient's age [2].

For adults, the typical dosage of methotrexate for rheumatoid arthritis ranges from 7.5 to 20 milligrams (mg) once a week, while for psoriasis, it can range from 10 to 25 mg once or twice a week [1]. However, these dosages can vary based on the patient's response to treatment and other factors.

When it comes to older adults, the dosage of methotrexate may need to be adjusted due to age-related changes in drug metabolism and elimination [2]. Older adults may be more susceptible to the side effects of methotrexate, such as bone marrow suppression and liver toxicity [2]. Therefore, healthcare providers may start with a lower dosage and gradually increase it based on the patient's response and tolerance [2].

It is important to note that the dosage of methotrexate for cancer treatment is typically higher than for rheumatoid arthritis or psoriasis and is determined based on the patient's body surface area, weight, and other factors [1].

In summary, the dosage of methotrexate can change with age due to age-related changes in drug metabolism and elimination. Healthcare providers may start with a lower dosage and gradually increase it based on the patient's response and tolerance.

Sources:

[1] Methotrexate. (2021, March 12). MedlinePlus. Retrieved from <https://medlineplus.gov/druginfo/meds/a68/007955.html>

[2] Methotrexate for Rheumatoid Arthritis. (2021, February 26). American College of Rheumatology. Retrieved from <https://www.rheumatology.org/I-Am-A/Patient-Caregiver/Treatments/Methotrexate-for-Rheumatoid-Arthritis>

[3] Methotrexate. (n.d.). DrugPatentWatch. Retrieved from <https://www.drugpatentwatch.com/drugs/methotrexate>