FLOT is the name of a chemotherapy combination. You might have it as a treatment for cancer of the stomach, food pipe or the area where the stomach joins the food pipe.

What is FLOT?

FLOT is the name of a combination of chemotherapy drugs that includes:

  • F - fluorouracil
  • L – leucovorin, also known as folinic acid or calcium folinate
  • O – oxaliplatin
  • T - docetaxel

It is a treatment for cancer of the:

  • stomach
  • food pipe (oesophagus)
  • area where the stomach joins the food pipe (gastro oesophageal junction)

You usually have FLOT before and after surgery to remove the cancer.

How does FLOT work?

Fluorouracil, oxaliplatin and docetaxel are chemotherapy drugs. These chemotherapy drugs destroy quickly dividing cells, such as cancer cells.

Leucovorin is a drug that helps fluorouracil to work better.

How do you have FLOT?

You have FLOT into your bloodstream (intravenously).

You have treatment through a long plastic tube that goes into a large vein in your chest. The tube stays in place throughout the course of treatment. This can be a:

  • central line
  • PICC line
  • portacath

If you don't have a central line

You might have treatment through a thin short tube (a cannula) that goes into a vein in your arm. You have a new cannula each time you have treatment.

When do you have FLOT?

You have FLOT chemotherapy as cycles of treatment Open a glossary item. Each cycle lasts 2 weeks (14 days). You have chemotherapy only on day 1 of each cycle. 

You usually have 8 cycles altogether. You have surgery to remove the cancer after cycle 4. Then you usually start the 5th cycle 6 to 12 weeks after the operation.

A cycle of treatment looks like this:

Day 1
  • You have docetaxel as a drip into your bloodstream (intravenously) over an hour.
  • You have oxaliplatin as a drip into your bloodstream over 2 hours.
  • You have folinic acid as a drip into your bloodstream over 2 hours.
  • You have fluorouracil as a drip into your bloodstream over 24 hours.
Day 2
  • Your nurse removes the fluorouracil drip.
Day 3 to 14
  • You have no treatment.

You then start a new cycle of treatment.

You may have G-CSF as an injection. G-CSF helps the body produce white blood cells to reduce the risk of infection. Your healthcare team will let you know the day to start yours, as this varies between hospitals.


You have blood tests before and during your treatment. They check your levels of blood cells and other substances in the blood. They also check how well your liver and kidneys are working.

What are the side effects of FLOT?

Side effects can vary from person to person. They also depend on what other treatments you're having. 

When to contact your team

Your doctor, nurse or pharmacist will go through the possible side effects. They will monitor you during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:

  • you have severe side effects 

  • your side effects aren’t getting any better

  • your side effects are getting worse

Early treatment can help manage side effects better. 

Contact your advice line immediately if you have signs of infection, including a temperature above 37.5C or below 36C.

We haven't listed all the side effects here. Remember it is very unlikely that you will have all of these side effects. But you might have some of them at the same time.

Common side effects

These side effects happen in more than 10 in 100 people (more than 10%). You might have one or more of them. They include:

Increased risk of infection

Increased risk of getting an infection is due to a drop in white blood cells. Symptoms include a change in temperature, aching muscles, headaches, feeling cold and shivery and generally unwell. You might have other symptoms depending on where the infection is.

Infections can sometimes be life threatening. You should contact your advice line urgently if you think you have an infection. 

Breathlessness and looking pale

You might be breathless and look pale due to a drop in red blood cells. This is called anaemia.

Bruising, bleeding gums or nose bleeds

This is due to a drop in the number of platelets in your blood. These blood cells help the blood to clot when we cut ourselves. You may have nosebleeds or bleeding gums after brushing your teeth. Or you may have lots of tiny red spots or bruises on your arms or legs (known as petechiae).

Less commonly you might notice blood in your poo (stools) or wee (urine). Call your advice line if you have any signs of bleeding.

Allergic reaction

A reaction may happen during the infusion, causing a skin rash, itching, swelling of the lips, face or throat, breathing difficulties, fever and chills. Tell your nurse or doctor immediately if at any time you feel unwell. They will slow or stop your drip for a while and give you medicine to help relieve your symptoms.

You usually have medicine to help prevent an allergic reaction at least 24 hours beforehand.

Some allergic reactions can be life-threatening alert your nurse or doctor if notice any of these symptoms.

High temperature and shivering

You might get a high temperature (fever) or a sudden feeling of cold with shivering with a rise in temperature (rigor).

Contact your advice line or healthcare team immediately if you have this.

Loss of appetite

You might lose your appetite for various reasons while having cancer treatment. Sickness, taste changes or tiredness can put you off food and drinks.

High blood sugar levels

High blood sugar levels can cause headaches, feeling thirsty and blurred vision. You have regular tests to check your blood sugar levels. You may need to check your levels more often if you are diabetic.

Changes in levels of salts or minerals in your blood

You may have changes in levels of minerals and salts in your blood, such as low potassium and high sodium.

Less commonly you might have low levels of calcium in your blood. Symptoms include tingling in the lips, tongue, fingers and feet, muscle aches or spasms.

You have regular blood tests during treatment to check these levels.

Numbness of fingers and toes

Numbness or tingling in fingers or toes is often temporary and can improve after you finish treatment. Tell your healthcare team if you're finding it difficult to walk or complete fiddly tasks such as doing up buttons. 

Increased sensitivity to the cold

Oxaliplatin can make you more sensitive to the cold. It can affect your throat causing it to feel as though it is difficult to breathe and swallow. This can happen whilst you have oxaliplatin or within a few hours of it finishing. It’s only temporary but can feel quite frightening.

Opening and closing the fridge or freezer, touching metal, eating or drinking cold foods and changes in temperature from the weather can trigger this.

It can help wearing gloves and avoid very cold food and drink before and after oxaliplatin.

Let your nurse know straight away if it's affecting your breathing and swallowing.

Taste changes

Taste changes may make you go off certain foods and drinks. You may also find that some foods taste different from usual or that you prefer to eat spicier foods. Your taste gradually returns to normal a few weeks after your treatment finishes.


Let your doctor or nurse know if you have headaches. They can give you painkillers such as paracetamol to help.

Cough and shortness of breath

Tell your doctor or nurse if you are short of breath, have a tightening in your chest, wheeze or you have a cough. This could be due to spasms in the muscles of your airways or infection. Although rare, it could also be due to changes to the lung tissue, making it less flexible.

Contact your doctor straight away if you have sudden difficulty in breathing and a cough or high temperature.


Constipation Open a glossary item is easier to sort out if you treat it early. Drink plenty and eat as much fresh fruit and vegetables as you can. Try to take gentle exercise, such as walking. Tell your healthcare team if you think you are constipated. They can give you a laxative if needed.


Contact your advice line if you have diarrhoea. For example, in one day you have 2 or more loose bowel movements than usual. If you have a stoma, you might have more output than normal. Your doctor may give you anti diarrhoea medicine to take home with you after treatment.

Try to eat small meals and snacks regularly. It’s best to try to have a healthy balanced diet if you can. You don’t necessarily need to stop eating foods that contain fibre. But if your diet is normally very high in fibre, it might help to cut back on high fibre foods such as beans, nuts, seeds, dried fruit, bran and raw vegetables. 

Drink plenty to try and replace the fluid lost. Aim for 8 to 10 glasses per day.

Feeling or being sick

Feeling or being sick is usually well controlled with anti sickness medicines. It might help to avoid fatty or fried foods, eat small meals and snacks and take regular sips of water. Relaxation techniques might also help.

It is important to take anti sickness medicines as prescribed even if you don’t feel sick. It is easier to prevent sickness rather than treat it once it has started.

Mouth sores and ulcers

Mouth sores and ulcers can be painful. It helps to keep your mouth and teeth clean, drink plenty of fluids and avoid acidic foods such as lemons. Chewing gum can help to keep your mouth moist. Tell your doctor or nurse if you have ulcers.

Skin changes

Your skin may become red and sore or you may have an itchy rash. Less commonly your skin might become sensitive to sunlight, develop hives (raised, itchy rash), or areas of your skin might darken.

Tell your doctor if you have any rashes or itching. Don't go swimming if you have a rash because the chlorine in the water can make it worse.

If your skin gets dry or itchy, smoothing in unperfumed moisturising cream may help. Check with your doctor or nurse before using any creams or lotions. Wear a high factor sunblock if you’re going out in the sun.

Hair loss

You could lose all your hair. This includes your eyelashes, eyebrows, underarms, legs and sometimes pubic hair. Your hair will usually grow back once treatment has finished but it is likely to be softer. It may grow back a different colour or be curlier than before. Some people may have permanent hair loss although this is rare.

Tiredness and weakness

You might feel very tired and as though you lack energy.

Various things can help you to reduce tiredness and cope with it, for example exercise. Some research has shown that taking gentle exercise can give you more energy. It is important to balance exercise with resting.

Pain in your body

You might feel some pain from your body such as your back, tummy (abdomen), joints and bones. Speak to your doctor or nurse about what painkillers you can take to help with this.

Liver changes

You might have liver changes that are usually mild and unlikely to cause symptoms. They usually go back to normal when treatment finishes. You have regular blood tests to check for any changes in the way your liver is working.

Fluorouracil can cause liver cell damage, but this is rare.

Weight gain

You may gain weight while having this treatment. You may be able to control it with diet and exercise. Tell your healthcare team if you are finding it difficult to control your weight. 

Soreness, redness and peeling on the palms and soles of the feet

The skin on your hands and feet may become sore, red, or may peel. You may also have tingling, numbness, pain and dryness. This is called hand-foot syndrome or palmar plantar syndrome.

Moisturise your skin regularly. Your healthcare team will tell you what moisturiser to use.

Slow wound healing

Any wounds you might have can take longer to heal. Keep wounds clean to prevent infection. Contact your GP or specialist nurse if you are worried about a wound.

Heart changes 

You may have changes to how your heart works such as your heart rhythm. Tests such as a heart trace (ECG) Open a glossary item might pick this up. Less often you might get chest pain. Let your healthcare team know if this happens. Your doctor will make sure it is safe for you to have treatment.

It is rare but these drugs can cause other side effects such as a heart attack, lack of oxygen to the heart, inflammation of the heart muscle, an enlarged heart muscle or the heart not being able to pump enough blood (cardiac shock).

An increase in the level of uric acid in your blood 

High levels of uric acid in your blood can lead to a build up of crystals in body tissues and cause inflamed joints. You’ll have regular blood tests to check your levels. Drinking plenty of fluids helps to flush out the excess uric acid. You might also have medicines to control the uric acid levels.

Swelling of your hands, legs and feet

Swelling of the hands, legs and feet is due to fluid build up. This is called oedema. You might also notice a build up of fluid in other areas of the body. 

Let your doctor or nurse know if you have any swelling.

Inflammation and pain at or near the drip site

When you're having treatment into your bloodstream through a cannula Open a glossary item tell your nurse straight away if you have any redness, swelling, pain or discomfort at or nearby to your drip site during the infusion. 

Occasional side effects

These side effects happen in between 1 and 10 out of every 100 people (between 1 and 10%). You might have one or more of them. They include:

  • lack of fluid in the body (dehydration)

  • feeling dizzy

  • eye infection (conjunctivitis) – your eyes may feel gritty, itchy, sticky from pus and look red. You might have other eyesight changes such as blurred or double vision, watery eyes or quick eye movement from side to side (nystagmus)

  • inflammation of the membranes covering the brain and spinal cord (meninges) causing symptoms similar to meningitis such as stiff neck, headaches and unable to look at bright light

  • problems with moving your body causing weakness, clumsiness, loss of balance and falls

  • high blood pressure or much less commonly low blood pressure

  • blood clots that can be life threatening; signs are pain, redness and swelling where the clot is. Feeling breathless can be a sign of a blood clot in the lung. Contact your advice line or doctor straight away if you have any of these symptoms

  • a sudden feeling of being hot and your skin going red (flushing)

  • hiccups

  • indigestion symptoms include heartburn, bloating and burping

  • sweating a lot more than usual

  • nail problems such as thickening, darkening of the nails or a blue tinge, or they might be brittle, flaky, and painful.

  • problems passing urine – it might be painful, you might go more often than usual or you might not be able to pass urine

  • changes to how your kidneys work - you have regular blood tests to check for this

  • mood changes such as feeling very low (depressed). Rarely you may feel the opposite and feel very happy (euphoria)

  • sleeping problems such as trouble getting to or staying asleep. Rarely you may feel the opposite and feel very sleepy.

Rare side effects

These side effects happen in fewer than 1 in 100 people (less than 1%). You might have one or more of them. They include:

  • imbalance of substances in your blood (metabolic acidosis) – it can cause confusion, tiredness, shortness of breath and headaches

  • feeling nervous

  • hearing changes that could lead to deafness but this is very rare

  • blockage or slow movement of the gut

  • shaking and trembling, stiffness and slow movement (symptoms of Parkinson's disease)

  • changes in the brain that are usually reversible, causing a sudden onset of symptoms including headaches, dizziness, confusion, fits (seizures) and changes to vision (reversible posterior leukoencephalopathy syndrome)

Other side effects

If you have side effects that aren't listed on this page, you can look at the individual drug pages:

Coping with side effects

We have more information about side effects and tips on how to cope with them.

What else do I need to know?

DPD deficiency

Between 2 and 8 out of 100 people (2 to 8%) have low levels of an enzyme called dihydropyrimidine dehydrogenase (DPD) in their bodies. A lack of DPD can mean you’re more likely to have severe side effects from capecitabine or fluorouracil. It might take you a bit longer to recover from the chemotherapy. These side effects can rarely be life threatening.

Before starting treatment with capecitabine or fluorouracil you have a blood test to check levels of DPD. So you may start treatment with a lower amount (dose) of the drug or have a different treatment. Your doctor or nurse will talk to you about this.

Other medicines, foods and drinks

Cancer drugs can interact with some other medicines and herbal products. Tell your doctor or pharmacist about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies.


Fluorouracil can raise the levels of phenytoin in your blood. You should have regular blood tests to prevent this from happening.


Fluorouracil contains sodium (salt). You might need to take account of this if you are on a controlled sodium diet. Tell your doctor if you are on a low salt diet.


Docetaxel contains small amounts of alcohol. This is not harmful to most people but maybe if you have liver disease, epilepsy or suffer from alcohol problems.

Pregnancy and contraception

This treatment may harm a baby developing in the womb. It is important not to become pregnant or get someone pregnant while you're having treatment and for at least 6 months afterwards.

Talk to your doctor or nurse about effective contraception before starting treatment. Let them know straight away if you or your partner become pregnant while having treatment. 

Loss of fertility

You may not be able to become pregnant or get someone pregnant after treatment with these drugs. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.

Men might be able to store sperm before starting treatment. And women might be able to store eggs or ovarian tissue. But these services are not available in every hospital, so you would need to ask your doctor about this.    


It is not known whether these drugs come through into the breast milk. Doctors usually advise that you don’t breastfeed during this treatment.

Treatment for other conditions

If you are having tests or treatment for anything else, always mention your cancer treatment. For example, if you are visiting your dentist.


Don’t have immunisations with live vaccines while you’re having treatment and for up to 12 months afterwards. The length of time depends on the treatment you are having. Ask your doctor or pharmacist how long you should avoid live vaccinations.

In the UK, live vaccines include rubella, mumps, measles, BCG, yellow fever and one of the shingles vaccines called Zostavax.

You can have:

  • other vaccines, but they might not give you as much protection as usual
  • the flu vaccine (as an injection)
  • the coronavirus (COVID-19) vaccine - talk to your doctor or pharmacist about the best time to have it in relation to your cancer treatment

Members of your household who are aged 5 years or over are also able to have the COVID-19 vaccine. This is to help lower your risk of getting COVID-19 while having cancer treatment and until your immune system Open a glossary item recovers from treatment.

Contact with others who have had immunisations - You can be in contact with other people who have had live vaccines as injections. Avoid close contact with people who have recently had live vaccines taken by mouth (oral vaccines) such as the oral typhoid vaccine. Sometimes people who have had the live shingles vaccine can get a shingles type rash. If this happens they should keep the area covered.

If your immune system is severely weakened, you should avoid contact with children who have had the flu vaccine as a nasal spray as this is a live vaccine. This is for 2 weeks following their vaccination.

Babies have the live rotavirus vaccine. The virus is in the baby’s poo for about 2 weeks and could make you ill if your immunity is low. Get someone else to change their nappies during this time if you can. If this isn't possible, wash your hands well after changing their nappy.

More information about this treatment

For further information about this treatment and possible side effects go to the electronic Medicines Compendium (eMC) website. You can find the patient information leaflet on this website.

You can report any side effect you have to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.

This page is due for review. We will update this as soon as possible.

  • Electronic Medicines Compendium
    Accessed April 2021

  • Immunisation against infectious disease: Chapter 6: General contraindications to vaccination
    Public Health England
    First published: March 2013 and regularly updated on the Gov.UK website

  • Evaluation of the introduction of primary G-CSF prophylaxis to FLOT chemotherapy regimen
    K-M Crampton and others
    Annals of Oncology, Gastrointestinal tumours, Non-colorectal, October 2019. Volume 30, Supplement 5

  • Perioperative chemotherapy with fluorouracil plus leucovorin, oxaliplatin, an docetaxel versus fluorouracil or capecitabione plus cisplatin and epirubicin for locally advanced, resectable gastric or gastro-oesophageal junction adenocarcinoma (FLOT4): a randomised, phase 2/3 trial.
    S-E Al-Batran and others
    The Lancet, 2019. Volume 393, Pages 1948 to 1957

  • NeoFLOT: Multicenter phase II study of perioperative chemotherapy in resectable adenocarcinoma of the gastrosectable junction or gastric adenocarcinoma – Very good response predominantly in patients with intestinal type tumours
    C Schulz and others
    International Journal of Cancer, 2015. Volume 137, Pages 678 to 685

  • The information on this page is based on literature searches and specialist checking. We used many references and there are too many to list here. Please contact patientinformation@cancer.org.uk with details of the particular issue you are interested in if you need additional references for this information.

Last reviewed: 
19 May 2021
Next review due: 
19 May 2024

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