Levoleucovorin injection is used to prevent harmful effects of methotrexate (Rheumatrex, Trexall) when methotrexate is used to to treat certain types of cancer. Levoleucovorin injection is also used to treat people who have accidentally received an overdose of methotrexate or similar medications. Levoleucovorin injection is in a class of medications called folic acid analogs. It works by protecting healthy cells from the effects of methotrexate while allowing methotrexate to enter and kill cancer cells.

Levoleucovorin injection comes as a powder to be mixed with liquid and injected intravenously (into a vein). It is usually given every 6 hours, until laboratory tests show it is no longer needed.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Before receiving levoleucovorin injection,

• Tell your doctor and pharmacist if you are allergic to levoleucovorin injection, leucovorin, folic acid (Folicet, in multi-vitamins), or any other medications.
• Tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: certain medications for seizures such as phenobarbital, phenytoin (Dilantin), and primidone (Mysoline); or trimethoprim-sulfamethoxazole (Bactrim, Septra). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• Your doctor may prescribe levoleucovorin along with 5-fluorouracil (5-FU). If you receive this combination of medications, you will be monitored very carefully because levoleucovorin may increase both the benefits and the harmful effects of 5-fluorouracil.
• Tell your doctor if you have anemia (low number of red blood cells) caused by lack of vitamin B12 or inability to absorb vitamin B12. Your doctor will not prescribe levoleucovorin to treat this type of anemia.
• Tell your doctor if you have or have ever had a buildup of fluid in the chest cavity or the stomach area, or kidney disease.
• Tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while receiving levoleucovorin injection, call your doctor.

Unless your doctor tells you otherwise, continue your normal diet.

Levoleucovorin injection and the medication(s) it is given with may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• Mouth sores
• Nausea
• Vomiting
• Diarrhea
• Heartburn
• Confusion
• Numbness, burning, or tingling in the hands or feet
• Changes in ability to taste food

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:

• Difficulty breathing
• Itching
• Rash
• Fever
• Chills

Levoleucovorin injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can’t be awakened, immediately call emergency services at 911.

Keep all appointments with your doctor and the laboratory.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.