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Wellcovorin Side Effects

Generic Name: leucovorin

Note: This document contains side effect information about leucovorin. Some of the dosage forms listed on this page may not apply to the brand name Wellcovorin.

For the Consumer

Applies to leucovorin: injectable, powder for solution, solution, tablet

Along with its needed effects, leucovorin (the active ingredient contained in Wellcovorin) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking leucovorin:


Check with your doctor as soon as possible if any of the following side effects occur while taking leucovorin:

Rare - reported with use in treatment of cancer

For Healthcare Professionals

Applies to leucovorin: compounding powder, injectable powder for injection, injectable solution, oral tablet


Adverse events attributed to use of leucovorin (the active ingredient contained in Wellcovorin) folinic acid by itself include allergic sensitization, including anaphylactoid reactions and urticaria; gastrointestinal and hematologic adverse events were common when used with fluorouracil.[Ref]


Very common (10% or more): Stomatitis (75%, when used with fluorouracil), nausea (74%, when used with fluorouracil), diarrhea (66%, when used with fluorouracil), vomiting (46%, when used with fluorouracil), dehydration (when used with fluorouracil)
Common (1% to 10%): Constipation (when used with fluorouracil)
Rare (less than 0.1%): Gastrointestinal disorders (after high doses)
Frequency not reported: Mucositis (when used with fluorouracil), cheilitis (when used with fluorouracil)[Ref]

When used with fluorouracil, diarrhea and dehydration have resulted in hospital admission and death.[Ref]


Very common (10% or more): Leucopenia (69%, when used with fluorouracil)
Common (1% to 10%): Thrombocytopenia (when used with fluorouracil)[Ref]


Very rare (less than 0.01%): Allergic reactions (sensitization, including anaphylactoid reactions, shock, and urticaria)
Frequency not reported: Stevens Johnson Syndrome and Toxic Epidermal Necrolysis (in combination with other agents)[Ref]


Very common (10% or more): Alopecia (42%, when used with fluorouracil), dermatitis (21%, when used with fluorouracil)
Frequency not reported: Palmar-plantar erythrodysesthesia (when used with fluorouracil)[Ref]


Very common (10% or more): Lethargy/malaise/fatigue (13%, when used with fluorouracil)
Uncommon (0.1% to 1%): Pyrexial reactions (following parenteral administration)[Ref]


Very common (10% or more): Anorexia (14%, when used with fluorouracil)
Frequency not reported: Hyperammonemia (when used with fluorouracil)


Common (1% to 10%): Infection (when used with fluorouracil)[Ref]

Nervous system

Rare (less than 0.1%): Increase in the frequency of attacks in epileptics, seizures, syncope[Ref]


Rare (less than 0.1%): Insomnia, agitation, depression[Ref]


1. Cerner Multum, Inc. "Australian Product Information." O 0

2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

3. "Product Information. Leucovorin Calcium (leucovorin)." Bedford Laboratories, Bedford, OH.

Some side effects of Wellcovorin may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.