colorectal cancercolon cancerrectal cancergastric cancer

FOLFIRI

Folinic Acid, Fluorouracil, and Irinotecan

FOLFIRI is a colorectal cancer chemotherapy regimen that replaces oxaliplatin with irinotecan. Often used after FOLFOX or when neuropathy is a concern.

14 days

Cycle length

12 cycles

Typical course

6

Side effects tracked

Common Side Effects

Diarrhea

acute (first 24 hours) and delayed (days 3–10)

Severe — call if worsens

Tip: Two types: early diarrhea during/after infusion (treatable with atropine) and late diarrhea days later (use loperamide aggressively at first sign).

Nausea

days 1–4

Moderate

Tip: Take prescribed anti-nausea medications on schedule. Ginger and small meals help between doses.

Fatigue

days 2–7

Moderate

Tip: Rest when tired. Light activity when possible. Fatigue often improves in the second week of each cycle.

Hair loss

weeks 2–4 of treatment

Moderate

Tip: Usually temporary. Discuss cold cap therapy with your oncology team if this is a concern.

Low blood counts (neutropenia)

days 7–14

Severe — call if worsens

Tip: Fever over 100.4°F with low counts is an emergency. Keep thermometer accessible at all times.

Mouth sores

days 3–10

Mild

Tip: Rinse with salt water frequently. Avoid spicy, acidic, or hard foods.

Critical Days in the Cycle

1

Day 1Infusion Day

Watch for

  • Early diarrhea (cholinergic reaction)
  • Cramping during infusion

When to call:

Diarrhea or sweating during infusion — nursing staff can give atropine.

3

Day 3Late Diarrhea Watch

Watch for

  • Loose stools beginning
  • Cramping
  • Dehydration signs

When to call:

More than 4 loose stools per day — start loperamide and call the team.

8

Day 8Nadir (Low Counts)

Watch for

  • Fever
  • Chills
  • Signs of infection

When to call:

Fever ≥100.4°F — go to the ER immediately, do not wait for a callback. Neutropenic fever can be life-threatening with low counts.

Frequently Asked Questions

What's the difference between FOLFIRI and FOLFOX?

FOLFIRI uses irinotecan instead of oxaliplatin. FOLFOX causes more neuropathy (nerve tingling), while FOLFIRI causes more diarrhea and hair loss. Your oncologist chooses based on your health profile and prior treatments.

How do I manage the diarrhea from FOLFIRI?

There are two phases. Early diarrhea (during/within hours of infusion): the nursing team can treat with atropine. Late diarrhea (day 3+): take loperamide (Imodium) at the first loose stool — don't wait. Call the team if you have more than 4 episodes per day.

Will my hair grow back after FOLFIRI?

Yes. Hair loss from FOLFIRI is temporary. Hair typically begins growing back 2–3 months after completing chemotherapy.

When should I call the oncology team?

For fever ≥100.4°F (38°C) during nadir — go to the ER immediately, do not wait for a callback. Call the team immediately for: severe diarrhea (more than 6 episodes per day or unable to keep fluids down), signs of dehydration (extreme thirst, dark urine, dizziness), or severe abdominal cramping.

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