In high-dose methotrexate therapy, leucovorin rescue is used to restore healthy cells. Which option best describes this purpose?

In high-dose methotrexate therapy, leucovorin rescue is used to restore healthy cells. Which option best describes this purpose?

• A. To enhance MTX effect
• B. To rescue healthy cells
• C. To increase MTX toxicity
• D. To replace hydration

Answer: (D)

Leucovorin rescue is used to protect normal, healthy cells after high-dose methotrexate by providing folinic acid, which bypasses the methotrexate-blocked enzyme and allows normal cells to continue making nucleotides. This helps spare healthy tissue from methotrexate toxicity while still letting the drug affect cancer cells. It does not enhance the methotrexate effect, increase its toxicity, or replace hydration. Hydration and urine alkalinization remain important to help clear the drug and protect the kidneys.

Leucovorin rescue is used to protect normal, healthy cells after high-dose methotrexate by providing folinic acid, which bypasses the methotrexate-blocked enzyme and allows normal cells to continue making nucleotides. This helps spare healthy tissue from methotrexate toxicity while still letting the drug affect cancer cells. It does not enhance the methotrexate effect, increase its toxicity, or replace hydration. Hydration and urine alkalinization remain important to help clear the drug and protect the kidneys.