How it is administered

Methotrexate is available in several forms:

• Oral tablets or oral solution: Taken by mouth, usually once weekly. Common strengths include 2.5 mg tablets and 2 mg/mL oral solution.
• Injection: Can be given intravenously (IV), intramuscularly (IM), subcutaneously (under the skin), or intrathecally (into the spinal fluid). Injectable forms are available as both preservative-free (for certain uses like intrathecal injection) and with preservative (for other routes).

Your healthcare provider will determine the best form and dose for you, depending on your diagnosis and treatment plan.

How it works

Methotrexate works by blocking an enzyme called dihydrofolate reductase. This enzyme is necessary for cells to make DNA, which is essential for cell growth and division. By inhibiting this enzyme, methotrexate interferes with the ability of cells—especially rapidly dividing cells like cancer cells—to grow and multiply.

In the treatment of acute lymphoblastic leukemia (ALL), methotrexate helps to stop the growth of abnormal white blood cells. It is particularly effective against cells that are dividing quickly, such as cancer cells in leukemia. However, it can also affect normal rapidly dividing cells in the body, which is why it can cause side effects.

Methotrexate is often used as part of a combination chemotherapy regimen, meaning it is given along with other medications to increase its effectiveness against leukemia.

Who Should take it

Methotrexate is indicated for adults and children with acute lymphoblastic leukemia (ALL) as part of a combination chemotherapy maintenance regimen. It is also used for other cancers, such as non-Hodgkin lymphoma and mycosis fungoides, and for some non-cancer conditions like rheumatoid arthritis, severe psoriasis, and polyarticular juvenile idiopathic arthritis (pJIA).

For ALL, methotrexate is typically used in the maintenance phase of treatment, after initial therapy has reduced the number of leukemia cells. It helps keep the disease in remission and prevent relapse. The exact dosing and schedule depend on the specific treatment protocol and the patient's age, weight, and overall health.

Who should not take it

Methotrexate should not be taken by:

• Pregnant women being treated for non-cancer conditions, as it can cause serious harm to the unborn baby. For cancer treatment, the risks and benefits must be carefully considered.
• Anyone with a history of severe hypersensitivity or allergic reactions to methotrexate.
• Patients with severe liver disease, severe kidney impairment, or active infections should not take methotrexate unless the benefits outweigh the risks and under close medical supervision.

Always inform your healthcare provider about your full medical history before starting methotrexate.

Commonly used with

Methotrexate is commonly used in combination with other chemotherapy drugs for the treatment of ALL. These may include medications such as vincristine, prednisone, asparaginase, mercaptopurine, and others, depending on the specific treatment protocol.

It may also be used with leucovorin (a form of folinic acid) as a "rescue" medication to help protect normal cells from some of methotrexate's side effects, especially at higher doses.

Commonly tested with

Methotrexate is often tested in combination with other chemotherapy agents in clinical trials for ALL and other blood cancers. Commonly tested combinations include methotrexate with vincristine, asparaginase, mercaptopurine, cytarabine, and corticosteroids.

It is also tested with supportive medications such as leucovorin to reduce toxicity, and with antibiotics or antifungals to prevent infections during chemotherapy.