This information is about a medicine called leucovorin, which is sometimes known as folinic acid (FA) or calcium folinate. Leucovorin is not a chemotherapy drug but is often given as part of chemotherapy treatment either to make the chemotherapy more effective, or reduce the risk of side effects. This information discusses leucovorin when it's given with the chemotherapy drugs fluorouracil (5FU) or methotrexate.

If you have any further questions you can ask your doctor or nurse at the hospital where you are having your treatment, or speak to one of our cancer support service nurses.

Leucovorin is often given with 5FU chemotherapy to treat cancers of the colon, rectum and other parts of the digestive system. Adding leucovorin has been shown to increase the effectiveness of the 5FU. Leucovorin may also be given with the chemotherapy drug tegafur-uracil (Uftoral®), which is similar to 5FU.

Leucovorin is also commonly given with methotrexate chemotherapy which is used to treat many different types of cancer. It's mainly given with higher doses of methotrexate and can help to reduce the side effects. It is sometimes known as 'folinic acid rescue'.

Leucovorin is a clear, pale-yellow fluid. It is also available as tablets.

Leucovorin can be given:

• by injection into a vein (intravenously) through a fine tube (cannula) put into the vein, usually in the back of the hand; through a fine plastic tube that is inserted under the skin into a vein near the collarbone (central line); or into a fine tube that is inserted into a vein in the crook of your arm (PICC line)
• by drip (infusion) into a cannula or line
• by injection into a muscle (intramuscular injection)
• as tablets swallowed with a drink.

If you are given tablets to take, it is important to take them as directed by your doctor.

Side effects of folinic acid are rare. However, sometimes you may have a high temperature after the drug has been given. Your doctor may prescribe some tablets to help relieve this effect. Any side effects that occur are much more likely to be related to the chemotherapy you have had. However, if you notice any side effects that you think may be related to the leucovorin, please discuss them with your doctor or chemotherapy nurse.

This section is based on our Leucovorin factsheet which has been compiled using information from a number of reliable sources, including:

• Martindale: The Complete Drug Reference (35th edition). Sweetman et al. Pharmaceutical Press, 2007.
• British National Formulary (56th edition). British Medical Association and Royal Pharmaceutical Society of Great Britain, September 2008.
• The Medicines.org.uk website – www.medicines.org.uk (November 2008).

For further references, please see the general bibliography.