Table of Contents
- What is Methotrexate?
- Conditions Treated with Methotrexate
- How Methotrexate Works
- How Methotrexate is Administered
- Methotrexate in Combination Therapies
- Potential Side Effects
- Ongoing Research and Future Directions
What is Methotrexate?
Methotrexate is a versatile medication used to treat various conditions. It is known by several other names, including MTX, amethopterin, and Trexall®[1]. Methotrexate belongs to a class of drugs called antimetabolites, which work by interfering with the growth of certain cells in the body[2].
Conditions Treated with Methotrexate
Methotrexate is used to treat a wide range of conditions, including:
- Rheumatoid Arthritis: A chronic inflammatory disorder affecting the joints[3]
- Crohn’s Disease: A type of inflammatory bowel disease[4]
- Certain types of cancer: Including leukemia, lymphoma, and ovarian cancer[1][5]
- Large Granular Lymphocyte (LGL) Leukemia: A rare type of blood cancer[6]
- Alopecia Areata: An autoimmune disorder causing hair loss[7]
- Colorectal Cancer: When used in combination with other medications[8]
How Methotrexate Works
Methotrexate works in different ways depending on the condition being treated:
- For cancer: It interferes with the growth of cancer cells, stopping them from dividing and multiplying[5].
- For autoimmune conditions: It suppresses the immune system, reducing inflammation and slowing down the progression of the disease[3].
- For LGL Leukemia: It helps normalize blood cell counts and reduce symptoms associated with the disease[6].
How Methotrexate is Administered
Methotrexate can be administered in several ways:
- Oral tablets: Taken by mouth, often on a weekly basis[6]
- Injections: Given under the skin (subcutaneous) or into a muscle[9]
- Intravenous infusion: Delivered directly into a vein[3]
The dosage and frequency of administration depend on the condition being treated and the patient’s response to the medication. For example, in rheumatoid arthritis, a common dosage is 7.5-25 mg per week[3].
Methotrexate in Combination Therapies
Methotrexate is often used in combination with other medications to enhance its effectiveness:
- With biological drugs like infliximab or ocrelizumab for rheumatoid arthritis[3]
- As part of a “metronomic” chemotherapy regimen for colorectal cancer, combined with drugs like capecitabine, cyclophosphamide, and celecoxib[8]
- With sirolimus for certain types of leukemia and lymphoma[1]
Potential Side Effects
Like all medications, methotrexate can cause side effects. Common side effects may include:
- Nausea and vomiting
- Fatigue
- Mouth sores
- Increased risk of infections
- Liver function abnormalities
To minimize side effects, doctors often prescribe folic acid supplements to patients taking methotrexate[3]. It’s important to discuss potential side effects with your healthcare provider and report any unusual symptoms promptly.
Ongoing Research and Future Directions
Researchers continue to study methotrexate to find new uses and improve its effectiveness:
- Investigating its use in combination with other drugs for various types of cancer[1]
- Exploring its effectiveness in treating alopecia areata (hair loss)[7]
- Studying different dosing regimens to optimize treatment for conditions like LGL leukemia[6]
These ongoing studies aim to expand our understanding of methotrexate and improve treatment outcomes for patients with various conditions.




