Litacor Dosage/Direction for Use

As an antidote for inadvertent overdosage of folic acid antagonists, it is recommended that leucovorin be administered via IM or IV in amounts equal to the weight of antagonist given, as soon as the overdosage is detected and preferably within the first hour. When large doses or overdoses of methotrexate are given, leucovorin can be administered by IV infusion in doses up to 75 mg within 12 hours, followed by 12 mg IM every 6 hours for 4 doses. When average doses of methotrexate appear to have an adverse effect, 6-12 mg of leucovorin may be given IM every 6 hours for 4 doses.
Leucovorin Rescue after High-Dose Methotrexate Therapy: Leucovorin rescue must begin within 24 hours of antifolate administration. A conventional leucovorin rescue dosage schedule is 10 mg/m² orally or parenterally followed by 10 mg/m² orally every six hours until the serum methotrexate concentration has declined to less than 10^-8M. If, however, at 24 hours following methotrexate administration the serum creatinine is increased by 50% or greater than the pre-methotrexate serum creatinine, the leucovorin dose should be immediately increased to 100 mg/m² every three hours until the serum methotrexate level is below 5 x 10^-8M.
Advanced Colorectal Cancer: Either of the following two regimens is recommended Leucovorin is administered at 200 mg/m² by slow intravenous injection over a minimum of 3 minutes, followed by 5-fluorouracil at 370 mg/m² by intravenous injection. Leucovorin is administered at 20 mg/m² by intravenous injection followed by 5-fluorouracil at 425 mg/m² by intravenous injection.
Treatment is repeated daily for five days. This five-day treatment course may be repeated at 4 week (28-day) intervals, for 2 courses and then repeated at 4 to 5 week (28 to 35 day) intervals provided that the patient has completely recovered from the toxic effects of the prior treatment course.
Or as prescribed by the physician.