Leucovorin

What is leucovorin?

Leucovorin is used to prevent some of the harmful effects of methotrexate when methotrexate is given in high doses. It is given to "rescue" normal cells from the effects of methotrexate.

Leucovorin may also be used with the drug fluorouracil in the treatment of some cancers.

You may hear leucovorin called folinic acid, leucovorin calcium, calcium folinate, or citrovorum factor. Leucovorin comes in a tablet, liquid, and injection forms.

Before giving leucovorin to your child

Tell your child's doctor if your child has ever reacted badly to leucovorin or to any other medication, food, colouring agents, or preservative.

Talk with the doctor or pharmacist if your child has any of the following conditions. This medicine may not be right for your child if they have:

• a history of seizures
• low vitamin B12 levels

How should you give your child leucovorin?

Leucovorin that is given after large doses of methotrexate or with fluorouracil is usually given by injection (needle) into your child's vein (intravenously or IV) while they are on a nursing unit. Sometimes your child will receive the first few doses by injection and then finish by taking their leucovorin by mouth.

Follow these instructions when you give your child leucovorin by mouth:

• Give your child leucovorin exactly as the doctor, pharmacist, or nurse tells you to.
• The timing of leucovorin doses is often very important. Make sure you understand how much leucovorin to give, at what times you should give it, and for how many doses.
• Talk to your child's doctor before you stop giving this medicine for any reason.
• You may give leucovorin with or without food.
• If your child is taking leucovorin tablets, you may wish to buy a pill-splitter to cut the tablet into 4 pieces or 2 pieces depending on what the doctor ordered.
• If your child is taking liquid leucovorin and the dose is not already in a syringe, measure the dose with the special spoon or syringe that the pharmacist gave you.
• If your child vomits a dose of leucovorin within 30 minutes of taking it, give another dose. If your child is having stomach upset (nausea) and throwing up (vomiting), not enough leucovorin may be absorbed into the body. Call your child's doctor right away to check what to do.

What should you do if your child misses a dose of leucovorin?

If your child misses a dose of leucovorin, check with your child's doctor or nurse right away. They may want to give your child an extra dose.

What are the possible side effects of leucovorin?

Most of the following side effects are not common, but they may be a sign of a serious problem. Call your child's doctor right away or take your child to Emergency if your child has any of these side effects:

• skin rash or itching
• difficulty breathing
• convulsions (seizures)

What safety measures should you take when your child is using leucovorin?

Check with your child's doctor or pharmacist before giving your child any other medicines (prescription, non-prescription, herbal, or natural products).

• Leucovorin may interfere with the action of trimethoprim and co-trimoxazole (Apo-Sulfatrim, Novo-Trimel, Septra, or Bactrim). Let the doctor or pharmacist know if your child is receiving these medications.
• Leucovorin may interfere with the action of some seizure medications. Let the doctor or pharmacist know if your child is taking phenobarbital, phenytoin (Dilantin), or primidone.

What other important information should you know about leucovorin?

• Leucovorin (folinic acid) is not the same as folic acid. Folic acid should not be substituted for leucovorin.
• Keep a list of all medications your child is on and show the list to the doctor or pharmacist.
• Do not share your child's medicine with others. Do not give anyone else's medicine to your child.
• Make sure you always have enough leucovorin to last through weekends, holidays, and vacations. Call your pharmacy at least 2 days before your child runs out of medicine to order refills.
• If your child is to go home on leucovorin by mouth, make sure you arrange a supply before leaving the hospital. Not all pharmacies will carry this medication.
• Keep leucovorin tablets at room temperature in a cool, dry place away from sunlight. Do NOT store it in the bathroom or kitchen.
• Keep leucovorin liquid in the refrigerator. Do not freeze this medicine.
• Do not keep any medicines that are out of date. Check with your pharmacist about the best way to throw away outdated or leftover medicines.
  

Keep leucovorin out of your child’s sight and reach and locked up in a safe place. If your child takes too much leucovorin, call your local Poison Information Centre at one of these numbers. These calls are free. 

• Call 1-844 POISON-X, or 1-844-764-7669, from anywhere in Canada except Quebec.
• Call 1-800-463-5060 if you live in Quebec.