How it is administered

Methotrexate can be administered in several forms:

• Oral tablets or oral solution: Swallowed by mouth. Available in strengths such as 2.5 mg tablets or 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 come in vials for healthcare provider administration.

The specific form and dose depend on the disease being treated, patient age, and other factors. For blood cancers, methotrexate is often part of a combination chemotherapy regimen and may be given by mouth or injection.

How it works

Methotrexate is a type of chemotherapy known as an antimetabolite. It works by blocking the activity of an enzyme called dihydrofolate reductase. This enzyme is necessary for cells to make DNA and other important molecules needed for cell growth and division.

By inhibiting this enzyme, methotrexate prevents cancer cells from making new DNA, which stops them from growing and multiplying. Because cancer cells (like those in blood cancers) grow and divide more quickly than most normal cells, they are more sensitive to methotrexate’s effects. However, some normal cells that divide rapidly (like those in the bone marrow, mouth, and gut) can also be affected, which leads to some of the side effects of the medication.

Methotrexate is used in various blood cancers, including acute lymphoblastic leukemia (ALL) and non-Hodgkin lymphoma, as part of combination chemotherapy regimens. It may also be used for other conditions like severe psoriasis and rheumatoid arthritis, but its main role in blood cancers is to slow or stop the growth of cancerous cells.

Who Should take it

Methotrexate is indicated for adults and children with certain types of blood cancers, including:

• Acute lymphoblastic leukemia (ALL): Used as part of a combination chemotherapy maintenance regimen.
• Non-Hodgkin lymphoma: Used in adults with relapsed or refractory disease as part of a metronomic combination regimen.
• Mycosis fungoides (cutaneous T-cell lymphoma): Used as a single agent or as part of combination chemotherapy.

It is also used for other cancers and some autoimmune diseases, but in the context of blood cancers, it is a key part of treatment protocols for leukemia and lymphoma. The specific dosing and schedule depend on the type of cancer, the stage, and other individual factors. Your healthcare team will determine if methotrexate is appropriate for your situation.

Who should not take it

Methotrexate should not be taken by:

• Pregnant women (when used for non-cancer conditions), as it can cause severe harm or death to an unborn baby. For cancer treatment, the risks and benefits must be carefully weighed.
• People with a history of severe hypersensitivity reactions (including anaphylaxis) to methotrexate.
• Patients with severe liver or kidney disease or certain blood disorders may not be able to safely use methotrexate.

If you are of childbearing potential, you must use effective contraception during treatment and for a period after stopping methotrexate (6 months for females, 3 months for males). Always inform your healthcare provider of all your medical conditions and medications before starting methotrexate.

Commonly used with

Methotrexate is commonly used with other chemotherapy drugs as part of combination regimens for blood cancers. These may include:

• Vincristine
• Doxorubicin
• Cyclophosphamide
• Cytarabine
• Mercaptopurine
• Prednisone

The exact combination depends on the type of blood cancer and the treatment protocol. Methotrexate may also be used with leucovorin (a form of folic acid) to help reduce side effects in some regimens.

Commonly tested with

Methotrexate is often tested with other chemotherapy agents in clinical trials and treatment protocols for blood cancers. These can include:

• Vincristine
• Doxorubicin
• Cyclophosphamide
• Cytarabine
• Mercaptopurine
• Prednisone
• Leucovorin (for rescue therapy)

These combinations are designed to target cancer cells in different ways and improve treatment effectiveness.