Methotrexate

Chemical name: Methotrexate, also known as amethopterin

Brand names: Mexate, Folex, Rheumatrex

Class: Antimetabolite chemotherapy. Fluorouracil, Gemzar, and Xeloda are other antimetabolites.

How it works: Antimetabolites kill cancer cells by acting as false building blocks in a cancer cell's genes, causing the cancer cell to die as it gets ready to divide.

Uses: Methotrexate often is used in combination with other chemotherapy medicines to treat:

• early-stage breast cancer after surgery and other treatments
• advanced-stage breast cancer

How it's given: Methotrexate is given intravenously.

Side effects:

• nausea
• vomiting
• joint pain
• diarrhea
• swelling in the feet and legs
• mouth sores
• hair changes
• rash
• loss of appetite
• irregular periods -- this can include temporary cessation (usually resume after medication is completed) or permanent cessation of menstrual periods depending on your age and other factors