Classification: Folic Acid Antagonist
Leucovorin is not a chemotherapy medication, but is given in conjunction with chemotherapy. Leucovorin can be used with the chemotherapy drug fluorouracil (5-FU). In this case, it is used to enhance the effects of the fluorouracil (i.e. to make the drug work better).
Leucovorin is also given with a chemotherapy agent called methotrexate, but in this case it is given to "rescue" normal, healthy cells from the damage caused by the methotrexate. In order to give the methotrexate time to kill the cancer cells, leucovorin is started 12-24 hours after the methotrexate is given.
This medication can be given in an intravenous (IV) or oral form (by mouth). The dosage is based on the particular protocol being used by the doctor. You should not take supplemental folic acid while receiving leucovorin, as this may enhance the effect to an undesirable degree.
Leucovorin rarely has side effect, any experienced are generally associated with the chemotherapy that is given with the leucovorin, rather than the leucovorin itself. In the case of fluorouracil, leucovorin may make the side effects of that medication worse. When used with methotrexate, it helps to lessen the severity of side effects. In rare cases, rash, hives, itching and wheezing have been reported with leucovorin.