It is very important that your doctor check your closely to make sure that this medicine is working properly. Blood and urine tests will be needed to check for unwanted effects.
Do not take other medicines unless they have been discussed with your doctor. This includes 5-fluorouracil (Adrucil®) and combination of trimethoprim and sulfamethoxazole (Bactrim®, Septra®). Using any of these medicines together with levoleucovorin increases your risk of serious side effects. .