FOLFIRI is a chemotherapy regimen for treatment of advanced colorectal cancer, consisting of concurrent treatment with irinotecan, leucovorin (folinic acid), and fluorouracil.

The regimen consists of:

• Irinotecan (180 mg/m² IV over 90 minutes) concurrently with folinic acid (400 mg/m² 2 x 250 mg/m² IV over 120 minutes).

• Followed by fluorouracil (400-500 mg/m² IV bolus) then fluorouracil (2400-3000mg/m² intravenous infusion over 46 hours).

This cycle is typically repeated every two weeks.