Leucovorin Drug Information

    Generic name: LEUCOVORIN CALCIUM

    Save on Leucovorin at your pharmacy Compare prices near you and start saving today—no enrollment required.
    See Prices

    Uses of Leucovorin

    Leucovorin calcium rescue is indicated after high dose methotrexate therapy in osteosarcoma. Leucovorin calcium is also indicated to diminish the toxicity and counteract the effects of impaired methotrexate elimination and of inadvertent over dosages of folic acid antagonists. Leucovorin calcium is indicated in the treatment of megaloblastic anemias due to folic acid deficiency when oral therapy is not feasible.

    Leucovorin is also indicated for use in combination with 5-fluorouracil to prolong survival in the palliative treatment of patients with advanced colorectal cancer. Leucovorin should not be mixed in the same infusion as 5-fluorouracil because a precipitate may form.

    Dosage & Administration of Leucovorin

    Clinical SituationLaboratory Findings
    NormalMethotrexateEliminationSerum methotrexate level approximately 10 micromo-molar at 24 hours after administration, 1 micromolar at 48 hours, and less than 0.2 micromolar at 72 hours.
    Delayed LateMethotrexateEliminationSerum methotrexate level remaining above 0.2 micrommolar at 72 hours, and more than 0.05 micromolar 96 hours after administration.
    Delayed EarlyMethotrexateElimination and/orEvidence of Acute Renal InjurySerum methotrexate level of 50 micromolar or more at 24 hours, or 5 micromolar or more at 48 hours after administration, OR; a 100% or greater increase in serum creatinine level at 24 hours after methotrexate administration (e.g., an increase from 0.5 mg/dL to a level of 1 mg/dL or more).

    Side Effects of Leucovorin

    Allergic sensitization, including anaphylactoid reactions and urticaria, has been reported following the administration of both oral and parenteral leucovorin. No other adverse reactions have been attributed to the use of leucovorin per se. The following table summarizes significant adverse events occurring in 316 patients treated with the leucovorin/5-fluorouracil combinations compared against 70 patients treated with 5-fluorouracil alone for advanced colorectal carcinoma.

    These data are taken from the Mayo/NCCTG large multicenter prospective trial evaluating the efficacy and safety of the combination regimen. PERCENTAGE OF PATIENTS TREATED WITH LEUCOVORIN/FLUOROURACIL FOR ADVANCED COLORECTAL CARCINOMA REPORTING ADVERSE EXPERIENCES OR HOSPITALIZED FOR TOXICITY (High LV*) /5-FU (Low LV † ) /5-FU 5-FU Alone (N=155) (N=161) (N=70) Any ‡ Grade 3 +§ Any ‡ Grade 3 +§ Any ‡ Grade 3 +§ (%) (%) (%) (%) (%) (%) Leukopenia 69 14 83 23 93 48 Thrombocytopenia 8 2 8 1 18 3 Infection 8 1 3 1 7 2 Nausea 74 10 80 9 60 6 Vomiting 46 8 44 9 40 7 Diarrhea 66 18 67 14 43 11 Stomatitis 75 27 84 29 59 16 Constipation 3 0 4 0 1 - Lethargy/Malaise/Fatigue 13 3 12 2 6 3 Alopecia 42 5 43 6 37 7 Dermatitis 21 2 25 1 13 - Anorexia 14 1 22 4 14 - Hospitalization for Toxicity 5% 15% 7% * High LV = Leucovorin 200 mg/m 2 † Low LV = Leucovorin 20 mg/m 2 ‡ Any = percentage of patients reporting toxicity of any severity § Grade 3+ = percentage of patients reporting toxicity of Grade 3 or higher

    Warnings & Cautions for Leucovorin

    In the treatment of accidental overdosages of folic acid antagonists, intravenous leucovorin should be administered as promptly as possible. As the time interval between antifolate administration (e.g., methotrexate) and leucovorin rescue increases, leucovorin's effectiveness in counteracting toxicity decreases. In the treatment of accidental overdosages of intrathecally adminstered folic acid antagonists, do not adminster leucovorin intrathecally.

    LEUCOVORIN MAY BE HARMFUL OR FATAL IF GIVEN INTRATHECALLY. Monitoring of the serum methotrexate concentration is essential in determining the optimal dose and duration of treatment with leucovorin. Delayed methotrexate excretion may be caused by a third space fluid accumulation (i.e., ascites, pleural effusion), renal insufficiency, or inadequate hydration. Under such circumstances, higher doses of leucovorin or prolonged administration may be indicated.

    Doses higher than those recommended for oral use must be given intravenously. Because of the benzyl alcohol contained in certain diluents used for reconstituting Leucovorin Calcium for Injection, when doses greater than 10 mg/m 2 are administered, Leucovorin Calcium for Injection should be reconstituted with Sterile Water for Injection, USP, and used immediately (see DOSAGE AND ADMINISTRATION section). Because of the calcium content of the leucovorin solution, no more than 160 mg of leucovorin should be injected intravenously per minute (16 mL of a 10 mg/mL, or 8 mL of a 20 mg/mL solution per minute). Leucovorin enhances the toxicity of 5-fluorouracil. When these drugs are administered concurrently in the palliative therapy of advanced colorectal cancer, the dosage of 5-fluorouracil must be lower than usually administered.

    Although the toxicities observed in patients treated with the combination of leucovorin plus 5-fluorouracil are qualitatively similar to those observed in patients treated with 5-fluorouracil alone, gastrointestinal toxicities (particularly stomatitis and diarrhea) are observed more commonly and may be more severe and of prolonged duration in patients treated with the combination. In the first Mayo/NCCTG controlled trial, toxicity, primarily gastrointestinal, resulted in 7% of patients requiring hospitalization when treated with 5-fluorouracil alone or 5-fluorouracil in combination with 200 mg/m 2 of leucovorin and 20% when treated with 5-fluorouracil in combination with 20 mg/m 2 of leucovorin. In the second Mayo/NCCTG trial, hospitalizations related to treatment toxicity also appeared to occur more often in patients treated with the low dose leucovorin/5-fluorouracil combination than in patients treated with the high dose combination -11% versus 3%. Therapy with leucovorin and 5-fluorouracil must not be initiated or continued in patients who have symptoms of gastrointestinal toxicity of any severity, until those symptoms have completely resolved.

    Patients with diarrhea must be monitored with particular care until the diarrhea has resolved, as rapid clinical deterioration leading to death can occur. In an additional study utilizing higher weekly doses of 5-fluorouracil and leucovorin, elderly and/or debilitated patients were found to be at greater risk for severe gastrointestinal toxicity. Seizures and/or syncope have been reported rarely in cancer patients receiving leucovorin, usually in association with fluoropyrimidine administration, and most commonly in those with CNS metastases or other predisposing factors, however, a causal relationship has not been established. 5 The concomitant use of leucovorin with trimethoprim-sulfamethoxazole for the acute treatment of Pneumocystis carinii pneumonia in patients with HIV infection was associated with increased rates of treatment failure and morbidity in a placebo-controlled study.

    Drug Interactions with Leucovorin

    Drug Interactions Folic acid in large amounts may counteract the antiepileptic effect of phenobarbital, phenytoin and primidone, and increase the frequency of seizures in susceptible pediatric patients. Preliminary animal and human studies have shown that small quantities of systemically administered leucovorin enter the CSF primarily as 5-methyltetrahydrofolate and, in humans, remain 1 to 3 orders of magnitude lower than the usual methotrexate concentrations following intrathecal administration. However, high doses of leucovorin may reduce the efficacy of intrathecally administered methotrexate.

    Leucovorin may enhance the toxicity of 5-fluorouracil (see WARNINGS section).

    Pregnancy Safety for Leucovorin

    Pregnancy Teratogenic Effects: Pregnancy Category C Adequate animal reproduction studies have not been conducted with leucovorin. It is also not known whether leucovorin can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Leucovorin should be given to a pregnant woman only if clearly needed.

    Pediatric Use of Leucovorin

    Pediatric Use See PRECAUTIONS, Drug Interactions subsection. Geriatric Use: Clinical studies of leucovorin calcium did not show differences in safety or effectiveness between subjects over 65 and younger subjects. Other clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older patients cannot be ruled out.

    This drug is known to be excreted by the kidney and the risk of toxic reactions to the drug may be greater in patients with impaired renal function. Because elder patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.

    Contraindications for Leucovorin

    Leucovorin is improper therapy for pernicious anemia and other megaloblastic anemias secondary to the lack of vitamin B 12. A hematologic remission may occur while neurologic manifestations continue to progress.

    Overdosage Information for Leucovorin

    Excessive amounts of leucovorin may nullify the chemotherapeutic effect of folic acid antagonists.

    Drug information sourced from the FDA. This content is for informational purposes only and does not constitute medical advice. Consult a healthcare professional before making any medication decisions.

    Ready to save on Leucovorin?

    Compare prescription prices at over 70,000 pharmacies and start saving today—no enrollment required.

    Compare Leucovorin Prices