Considering the fact that Leucovorin is a form of folic acid, it is typically used to reduce the side effects caused by large doses of drugs that are taken to reduce the effects of folic acid. According to the definition posted on drugs.com, folic acid “helps your body produce and maintain new cells, and also helps prevent changes to DNA that may lead to cancer”. It is worth noting, though, that taking Leucovorin is not recommended if you have any type of anemia caused by Vitamin B12 deficiency. You should also tell your doctor if you have liver/kidney disease or if you have breathing problems before using Leucovorin. Bear in mind that it is still not known whether or not the medication in question could harm the fetus or the nursing baby. Therefore, consulting a doctor before using Leucovorin is necessary in case you’re pregnant/ breastfeeding. As for the side effects that might happen when you take this drug, they mostly include signs of an allergic reaction such as trouble breathing, hives, or swelling of face, lips, or throat. Of course, you must contact your doctor when you experience any of these signs.