Leucovorin: What to Expect, Side Effects, and More

Leucovorin is similar to the vitamin folic acid (B-9 vitamin).
 

Leucovorin (brand names: Wellcovorin, Citrovorum Factor, Folinic Acid) is typically given to people receiving the chemotherapy medicines fluorouracil or methotrexate.

See Leucovorin prescribing information.

 

How Leucovorin works

When given with fluorouracil, Leucovorin enhances fluorouracil’s binding to thymidylate synthase, thereby increasing its efficacy. 

When given with methotrexate, Leucovorin acts as a “rescue agent” — it reduces the side effects of methotrexate. Methotrexate kills both cancer and healthy cells by depleting their folic acid. Leucovorin helps to restore folic acid to healthy cells. 

 

What to expect during Leucovorin treatment

Leucovorin can be given orally, or intravenously through an IV or port. Dosage recommendations are dependent on the dose and route of the chemotherapy with which it is administered, but is typically taken every six hours for about a 24 hour period after the start of the chemotherapy infusion. 

 

Leucovorin side effects

Like almost all breast cancer medicines, Leucovorin can cause side effects, some of them severe. Most of the side effects you experience will be due to the chemotherapy you have received, and not from the leucovorin, but are listed below. 

The most common side effects of Leucovorin are:

More serious side effects can occur, including:

  • seizures

  • fainting

Pregnant women shouldn’t take Levoleucovorin as it’s given in combination with methotrexate or fluorouracil, which can cause embryo-fetal harm. 

Note: Leucovorin increases the toxicity of fluorouracil, which can worsen side effects.

 

Paying for Leucovorin

The cost of Leucovorin may vary. The price you’ll pay depends on the drug manufacturer, your health insurance provider and plan, where you live, and the pharmacy you use. 

Note: Your insurance company may require you to get prior authorization before covering Leucovorin. 

Learn more about financial assistance and medicine cost-lowering tips.

— Last updated on February 28, 2025 at 9:05 PM