Folinic acid (leucovorin or calcium folinate)
Folinic acid is also known as calcium folinate or leucovorin. It is used to make chemotherapy work better, or to reduce its side effects.
Folinic acid (also called calcium folinate or leucovorin) is not a chemotherapy drug. But it may be given with the chemotherapy drugs:
Folinic acid is often given with 5FU to treat cancers of the colon, rectum and other parts of the digestive system. It makes 5FU work better. It may also be given with tegafur-uracil which is a similar drug to 5FU.
Methotrexate is used to treat different types of cancer. Folinic acid is mainly used with higher doses of methotrexate to help reduce the side effects. This is sometimes called folinic acid rescue or leucovorin rescue.
Your doctor will talk to you about this treatment and its possible side effects before you agree (consent) to have treatment.
You will be given folinic acid in the chemotherapy day unit or during a stay in hospital. A chemotherapy nurse will give it to you at the same time as your chemotherapy.
During treatment you will usually see a cancer doctor, a chemotherapy nurse, or a specialist nurse, and a specialist pharmacist. This is who we mean when we mention doctor, nurse or pharmacist in this information.
Before or on the day of treatment, a nurse or person trained to take blood (phlebotomist) will take a blood sample from you. This is to check that your blood cells are at a safe level to have the chemotherapy part of the treatment.
You will see a doctor or nurse before you have treatment. They will ask you how you have been feeling. If your blood results are okay, the pharmacist will prepare your drugs. Your nurse will tell you when your treatment is likely to be ready.
You may have folinic acid as a drip (infusion) or injection through:
- a cannula – a short, thin tube the nurse puts into a vein in your arm or hand
- a central line – a fine tube that goes under the skin of your chest and into a vein close by
- a PICC line – a fine tube that is put into a vein in your arm and goes up into a vein in your chest
- an implantable port (portacath) – a disc that is put under the skin on your chest or arm and goes into a vein in your chest.
You may also have folinic acid as a tablet. Before you leave hospital, the nurse or pharmacist will give you the tablets to take at home. It is important to take your tablets exactly as explained. This is to make sure they work as well as possible for you.
Contact the hospital
Your nurse will give you telephone numbers for the hospital. If you feel unwell or need advice, you can call them at any time of the day or night. Save these numbers in your phone or keep them somewhere safe.
We cannot list every side effect for this treatment. There are some rare side effects that are not listed. You can visit the electronic Medicines Compendium (eMC) for more detailed information.
Side effects from folinic acid are rare. Sometimes you may have a high temperature (fever) after the drug has been given. Your doctor may prescribe some tablets to help with this.
Any side effects you have are likely to be related to the chemotherapy drugs. But if you notice any side effects that you think may be related to the folinic acid, talk to your doctor, nurse or pharmacist.
If you feel ill or have any severe side effects during cancer treatment, it is important to tell your doctor or nurse straight away.
Blood clot risk
Cancer and some cancer treatments can increase the risk of a blood clot. Symptoms of a blood clot include:
- throbbing pain, redness or swelling in a leg or arm
- suddenly feeling breathless or coughing
- sharp chest pain, which may be worse when you cough or take a deep breath.
If you have any of these symptoms, contact the hospital straight away on the 24-hour contact number you have been given. If you cannot get through to your doctor, call the NHS urgent advice number on 111.
A blood clot is serious, but it can be treated with drugs that thin the blood (anticoagulants). Your doctor or nurse can give you more information.
You can help reduce the risk of developing a blood clot by:
- staying active during treatment
- drinking plenty of fluids, especially water.
You may be given anticoagulants to help prevent a clot.
Some medicines can affect how this treatment works or be harmful when you are having it. Always tell your cancer doctor about any drugs you are taking or planning to take, such as:
- medicines you have been prescribed
- medicines you buy in a shop or chemist
- vitamins, herbal drugs and complementary therapies.
Tell other doctors, pharmacists or dentists who prescribe or give you medicines that you are having this cancer treatment.
You can visit the electronic Medicines Compendium (eMC) for more detailed information about your treatment.
Folinic acid tablets contain a small amount of lactose. If you have a lactose intolerance, talk to your doctor before taking folinic acid.
You are advised not to breastfeed while having this treatment, or for some time after treatment finishes. This is because the drugs could be passed to the baby through breast milk.
Your doctor or nurse can give you more information.
Medical and dental treatment
If you need medical treatment for any reason other than cancer, always tell the doctors and nurses you are having cancer treatment. Give them the contact details for your cancer doctor so they can ask for advice.
If you think you need dental treatment, talk to your cancer doctor or nurse. Always tell your dentist you are having cancer treatment.
This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert health professionals and people living with cancer.
Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.
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