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Regimen Information

For 5FU + Leucovorin, including Side Effects

5FU + Leucovorin

Drugs in this Regimen:

For the treatment of Colon Cancer

How 5FU + Leucovorin chemotherapy is given and possible side effects.

5FU + Leucovorin for the treatment of Colon Cancer

5FU + Leucovorin is a chemotherapy regimen used in the treatment of colon cancer. This treatment involves two chemotherapy drugs: leucovorin and fluorouracil, which is also known as 5FU.

Chemotherapy is often given as a combination of drugs. Combinations usually work better than single drugs because different drugs kill cancer cells in different ways.


  • Nausea & Vomiting

  • Risk of Infection

  • Anemia

  • Alopecia or Hair Loss

For more information, see the 'Expert Resources' tab below.

Community Responses

Often, the most helpful information regarding treatment side effects comes not from clinical brochures, but rather from other patients like you. We've collected the most helpful community resources to help you prepare for the side effects and coping tips for your chemotherapy regimen.

What side effects did you experience while on this medication?

The following have been voted the 3 most helpful responses to this question.

I'm Gloria Becker, and I'm a survivor of Colon Cancer

I’d like to begin by stating a fact. This particular therapy is one of the “mild” chemotherapy treatments.

Each person’s experience will be different. In my case, I responded well to the therapy. I experienced many side effects. Some of which included nausea, loss of appetite, fatigue, mouth sores, sensitivity to hot and cold (both in my hands and feet), and severe diarrhea. Some of these symptoms may have been caused by radiation. I was having both administered at the same time.

I had the option of surgery before chemo/radiation, but I chose to have chemo/radiation before surgery. The thought was to shrink the tumor before removing it. I was very fortunate to have made the choice of chemo/radiation first because when the surgeon performed the surgery there was only scar tissue visible. He had to call my oncologist to confirm that he was in the right place!

I also experienced a pulmonary embolism shortly after my surgery. It was not determined whether it was caused by the chemo. I also have a myeloproliferative neoplasm, which may have caused the embolism.

It has been nine years since my diagnosis of colon cancer. I have some residual side effects, but I am grateful for each day.

  • Thu Nov 8, 2012
I'm schoolboardlady, and I support someone with cancer

Isil, the side effects of chemo also depend on some of the predications your oncologist includes. I recently finished my 5th post-surgery FOLFOX, after four pre-surgery treatments. I put them together because the effects of Oxaliplatin are cumulative. I had 8 treatments with Oxaliplatin, approximately 1050 mg cumulatively. So, ask your oncologist how many cumulative mg’s does he/she plan for you.

Most important is that a premedication infusion of calcium and magnesium can GREATLY ameliorate the immediate effect of Oxaliplatin (one of the chemo drugs in the FOLFOX cocktail.) There is no reason not to offer you this premedication. My oncologist also gives me a steroid with each infusion and that help tremendously, limiting the inflammation reactions to the chemo, ESPECIALLY in my feet and hands, a side effect of FU-5.

Oxaliplatin has its own side effects, the neuropathy aggravated by cold, any temperature that differs more than 20 degrees from body temperature. Also, always ask if there will be any changes to your treatment because I had a bad surprise last treatment. My oncologist discontinued by Oxaliplatin (after 8 treatments which included it—BUT, doc also withdrew the steroid—which removed the protection of the skin on my feet, hands and even the skin around my well healed incision scare. ttps://

So, FU-5 and it’s equivalent in pill form XELODA, results in hand foot syndrome when a steroid is NOT given along with these chemotherapy drugs.

Lastly and very important, ask for a premedication of Aloxi or Emend for your first treatment, to tamp down nausea and or vomiting. Both drugs have been very effective for me, I’ve never actually vomited. During my last modified FOL-FOX (held the oxaliplatin), my onco also held the Emend (anti-emetic) and I did feel more nauseous for about five days—but it was mild. I took Emotrol OTC to tamp down the nausea feeling.

Beware, moth Aloxi and Emend can be TREMENDOUSLY constipating. Have Senekot handy. I take it on the Friday after my Thursday treatment day one, while I am still wearing the pump. It is critical to end run the constipation. Also, drink as much water as you can. You can also ask your chemo nurse for ’fluids" on the day you disconnect your pump—more fluids helps helps with everything.

  • Wed Nov 21, 2012
Hi, I'm Georgia girl

I haven’t started treatment yet. My colon surgery was last April 2018 and chose because of markers being low not to do chemo. But now a year later hemoglobin dropped and PTScan shows inflammation in colon and markers are up. I’m scared of treatments. Is it as severe as I have heard! I live alone , will I need someone with me during treatments!

  • Sun Jun 2, 2019
I'm schoolboardlady, and I support someone with cancer

How 5FU + Leucovorin is one of the milder combinations… but if you add Oxaliplatin to it—it becomes a very rough regimen. Add Avastin, and look forward to mild bleeding in nose and other mucous membranes…(that you can see….)

  • Wed Nov 21, 2012
Hi, I'm Al bevvino

loss taste buds
minor fatigue
minor numbness in feet
loss of appetite

  • Tue Aug 11, 2015

I’ve had some time do not have an appetite, and lost of taste buds with minor fatigue.
but the one key to all this drinking as much water as possible take the meds that are prescribe by you dr.

  • Sun Oct 11, 2015
I'm louthebug, and I support someone with cancer

My wife just finished her first round of chemo. She had colon cancer and 15" of her colon was removed along with part of her abdominal wall muscle since the cancer invade it. Her second round starts this Monday. The side effects so far have been a little hair thinning along with blistering on 3 of her fingers where the skin just peeled off. Also, her right thumb has no feeling in it. Her CEA levels have dropped from 243 pre surgery to now 9.4 after her first round. Her appetite has reduced a little but she can’t drink anything that is carbonated any more. Not sure if this will improve once all 12 treatments are done or not.

  • Thu May 30, 2019
Hi, I'm Georgia girl

I haven’t started treatment yet. My colon surgery was last April 2018 and chose because of markers being low not to do chemo. But now a year later hemoglobin dropped and PTScan shows inflammation in colon and markers are up. I’m scared of treatments. Is it as severe as I have heard! I live alone , will I need someone with me during treatments!

  • Sun Jun 2, 2019

This discussion needs your voice!

What were the specific side effects that you experienced while taking this medication? How did you manage them?

What coping tips would you give to new patients on this regimen?

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This discussion needs your voice!

What do you wish you had known before taking this medication? What information would you like to pass on to patients who are beginning this medication?

Treatment Overview

This chemotherapy regimen is commonly used to treat:

Other chemotherapy regimens for the treatment of Colon Cancer:

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