Levoleucovorin Dosage

Medically reviewed by Drugs.com. Last updated on Jul 3, 2023.

Applies to the following strengths: 50 mg; 175 mg; 10 mg/mL; 300 mg

Usual Adult Dose for:

Methotrexate Rescue
Methotrexate Overdosage

Additional dosage information:

Renal Dose Adjustments
Liver Dose Adjustments
Precautions
Dialysis
Other Comments

Usual Adult Dose for Methotrexate Rescue

Rescue after high dose methotrexate therapy, based on a methotrexate (MTX) dose of 12 grams/m2 IV over 4 hours, depending on methotrexate clearance:

7.5 mg (approximately 5 mg/m2) IV every 6 hours for 10 doses

Start 24 hours after beginning of methotrexate infusion.

Normal Methotrexate Clearance (serum MTX approximately 10 micromolar 24 hour after administration, 1 micromolar at 48 hours, less than 0.2 micromolar at 72 hours): Follow above dosing

Delayed Methotrexate Clearance (serum MTX above 0.2 micromolar at 72 hours, and more than 0.05 micromolar at 96 hours):
Continue 7.5 mg IV every 6 hours until MTX level is less than 0.05 micromolar

Delayed Early Methotrexate Elimination (serum MTX 50 micromolar or higher at 24 hours, or 5 micromolar or higher at 48 hours)
and/or
Evidence of Acute Renal Injury (100% or greater increase in serum creatinine at 24 hours after MTX administration; e.g. increase from 0.5 mg/dL to 1 mg/dL or above):
75 mg IV every 3 hours until MTX level is less than 1 micromolar; then 7.5 mg IV every 3 hours until MTX level is less than 0.05 micromolar

Comments:

Measure serum creatinine and methotrexate levels at least once daily.
Continue levoleucovorin, hydration, and urinary alkalinization (pH of 7.0 or higher) until methotrexate level is below 0.05 micromolar.
Patients with delayed early methotrexate elimination are likely to develop reversible renal failure; continue hydration and urinary alkalinization, and closely monitor fluid and electrolyte status until MTX is under 0.05 micromolar and renal failure has resolved.
If significant clinical toxicity is observed, continue levoleucovorin for an additional 24 hours (total of 14 doses over 84 hours) in subsequent courses of therapy.
Consider that other medications that interact with methotrexate may be being used when laboratory abnormalities or clinical toxicities are seen.
Delayed methotrexate excretion may be from accumulation in a third space fluid collection (i.e. ascites, pleural effusion), renal insufficiency, or inadequate hydration; higher levoleucovorin doses or prolonged administration may be indicated.
Although this drug may ameliorate methotrexate's hematologic toxicity, it has no effect on other toxicities such as nephrotoxicity.

Use(s): As a rescue after high dose methotrexate therapy in osteosarcoma

Usual Adult Dose for Methotrexate Overdosage

7.5 mg IV every 6 hours until serum methotrexate is less than 0.01 micromolar

If serum creatinine increased 50% over baseline, or methotrexate is over 5 micromolar at 24 hours or 0.9 micromolar at 48 hours, increase levoleucovorin dose to 50 mg/m2 IV every 3 hours until methotrexate level is less than 0.01 micromolar

Comments:

Begin as soon as possible after the overdosage and within 24 hours of methotrexate when there is delayed excretion.
As the time interval between methotrexate and levoleucovorin administration increases, the effectiveness of levoleucovorin decreases.
Determine serum creatinine and methotrexate levels at 24 hour intervals.
Use concomitant hydration (3 L/day) and urinary alkalinization to maintain a pH of 7.0 or greater.

Use(s): Inadvertent methotrexate overdosage