Fluorouracil (injection, intravenous)

Fluorouracil interferes with the growth of cancer cells and is used to treat cancer of the breast, stomach, rectum, pancreas and other cancers too.


Fluorouracil is a chemotherapy medication of the group antimetabolites. It is used in the treatment of cancers of the stomach, pancreas, breast, rectum and other cancers too.

Fluorouracil works by interfering with the growth and development of cancer cells in the body so that the cancer can eventually be destroyed. The growth of healthy cells is also affected by this treatment as the medication cannot distinguish between healthy and cancerous cells. This means that unwanted side effects are likely to occur and in some cases, these can be serious and will require urgent medical attention. Other side effects including the loss of hair can cause concern despite not being medically serious. Some side effects from the use of this treatment may not occur for a period of months or even years after cessation of use.

Before beginning treatment with fluorouracil, you must discuss the benefits of use in relation to the risks of use to determine the best course of action for you.

Fluorouracil is only available when prescribed and is to be administered only under the direct supervision of a doctor. Fluorouracil is administered as adrucil by injection into the vein of the patient.

Condition treated

Type Of Medicine

  • Chemotherapy
  • Antimetabolite

Side Effects

In addition to the required effects from the use of Fluorouracil, other side effects will also occur. This is because the medication will also attack healthy cells in the body. In some cases, urgent medical attention will need to be sought for the treatment of certain side effects. In other cases, side effects will be less serious and will not require medical attention.

It is also important to note that side effects from the use of this treatment may occur months or even years after treatment. Delayed effects can be very serious and can include the development of certain types of cancer such as leukemia. You should ensure that you have discussed this with your doctor before beginning use of Fluorouracil.

You should contact your doctor immediately if any of the following side effects occur:

Occurring more commonly:

Occurring less commonly:

  • Black stools with a tarry appearance
  • Chills
  • Coughing or hoarseness experienced with feverishness or chills
  • Feverishness
  • Lower back pain and/or side pain experienced with feverishness or chills
  • Pain or difficulty experienced during urination that is experienced with feverishness or chills
  • Severe nausea
  • Severe vomiting
  • Stomach cramping

Occurring only rarely:

  • Blood appearing in urine or stools
  • Red spots or patches appearing on the skin
  • Unusual bleeding
  • Unusual bruising

If any of the following side effects are experienced then you should check with your doctor as soon as possible:

Occurring only rarely:

  • Chest pains
  • Coughing
  • Shortness of breath without exertion
  • Tingling of hands and feet developing into pain, redness and/or swelling
  • Difficulty balancing

Other side effects may also occur that would not normally require you to seek medical attention for treatment. If the following side effects become bothersome or are ongoing, however, then you can seek advice from your doctor:

  • Dry or cracking skin
  • Feeling of weakness
  • Itching
  • Loss of usual appetite
  • Nausea
  • Skin rash
  • Vomiting

The use of fluorouracil can cause the patient to suffer from temporary hair loss. Once treatment with fluorouracil has come to an end the normal growth of hair will usually return in patients although some lasting changes to hair color or appurtenance may occur as it grows back.

Side effects can also continue to occur after cessation of treatment. In the period following the end of treatment patients will need to remain alert to side effects and to symptoms of other medical conditions.

Other side effects that have not been listed herein can also occur from the use of fluorouracil. If you experience any other side effects then you should report them to your doctor for advice. If, however, you are concerned about your immediate health then you should always contact the emergency services.


This medication should only ever be used under the direct supervision of a doctor.

Patients may also be given other medications to take in conjunction with fluorouracil. If you are using a combination of medications for treatment then it is essential that the correct pattern of use be followed. When taking some orally you should check with your doctor how best to take the tablets in conjunction with this injection for the full effect. You should develop a plan for dosing that ensures you are able to take all of your medications at the correct time.

Fluorouracil will often cause you to vomit and feel unwell. Despite this, it is vital that you continue use and you should not stop treatment. You can discuss how to lessen these effects with your doctor before you begin treatment but should not stop treatment because of this.

The dose of medication given to each patient will differ for this medication depending on a range of factors including the strength of the dose, the weight of the patient and the condition being treated as well as a range of other factors. Your doctor will determine the appropriate dose for your condition and it will be administered under the supervision of a doctor.


Fluorouracil should not be used in conjunction with a range of different medications. Medications can interact in the body with severe unwanted side effects and some medications can prevent others from working or can increase the risk of certain side effects occurring.

Fluorouracil is not recommended for use in conjunction with the following medications. Your doctor may decide not to prescribe this medication or may prevent the use of another:

  • Varicella Virus Vaccine
  • Tegafur
  • Rubella Virus Vaccine, Live
  • Rotavirus Vaccine, Live
  • Mumps Virus Vaccine, Live
  • Measles Virus Vaccine, Live
  • Brivudine

The use of the following medications in conjunction with fluorouracil is not normally recommended but in some cases may be the best treatment available for you. If both treatments are prescribed then your doctor may adjust the frequency of use or dose of one or both medications:

  • Yellow Fever Vaccine
  • Warfarin
  • Typhoid Vaccine
  • Tinidazole
  • Tamoxifen
  • Smallpox Vaccine
  • Secnidazole
  • Poliovirus Vaccine, Live
  • Phenprocoumon
  • Oxypurinol
  • Ornidazole
  • Nimorazole
  • Metronidazole
  • Methotrexate
  • Isoconazole
  • Influenza Virus Vaccine, Live
  • Clozapine
  • Cimetidine
  • Cholera Vaccine, Live
  • Benznidazole
  • Bacillus of Calmette and Guerin Vaccine, Live
  • Azanidazole
  • Allopurinol
  • Adenovirus Vaccine
  • Acenocoumarol

The following medications can increase the risk of certain side effects occurring. In some cases, the use of both treatments may still be the best treatment for you but your doctor may make changes to the dose given or to the frequency of treatment to reduce the risk:

  • Thiamine
  • Phenytoin
  • Levoleucovorin
  • Levamisole
  • Leucovorin
  • Fosphenytoin

Other drug interactions with fluorouracil can also occur. Patients should ensure that the doctor is aware of all other substances they are taking before beginning treatment. This includes all prescribed treatments, vitamin supplements, dietary aids, over the counter treatments and herbal remedies. All of these could potentially interact with fluorouracil in the body with severe consequences.

Other medical problems from which you suffer can also impact the use of fluorouracil. Certain conditions may be worsened by treatment and the body may be less able to fight infections. You should inform your doctor of all medical conditions from which you suffer before beginning use. This is especially important in the following cases

Other conditions not listed herein could also impact the use of fluorouracil. Ensure your doctor is aware of all conditions from which you have suffered in the past and present.


Fluorouracil is a very serious medication that will have unpleasant side effects. Before beginning use, you should weigh the benefits of use against the risks of using this treatment. The decision to begin treatment should be made in conjunction with your doctor having ensured that the following has all been considered:

Allergies' You must inform your doctor of all allergies from which you suffer. This is particularly important if you have ever reacted badly to any kind of medication in the past.

Pediatric ' Use in children is not expected to have different effects than when used on adults. There has not, however, been any specific study made into this use. You should discuss use in children with your doctor.

Geriatric ' There is no known limitation to the use in elderly patients. Elderly patients are more likely to have medical conditions including liver disease or kidney disease that may impact the dose of treatment that is given. Caution should be exercised where these conditions are present in all age groups.

Pregnancy ' This medication should not be taken by pregnant women. If you are pregnant then you must inform your doctor before use as this medication is known to cause fetal abnormalities. Patients of childbearing age must also take steps to prevent pregnancy during use. Two forms of contraception should be used in sexually active patients to prevent pregnancy. Male patients should also use protection to prevent the impregnation of their sexual partners during use of this treatment. Both male and female patients must be advised to avoid pregnancy during use and for at least 6 months following cessation of use of this treatment. Men should also be advised to preserve sperm before treatment as there is a risk of the occurrence of irreversible infertility that may occur from the use of this treatment.

Breastfeeding ' Patients should not breastfeed an infant during the use of this medication. Safe breastfeeding may be possible during intermittent treatment, but the risks must be considered in relation to the potential benefits. Discuss this with your doctor.

During use of this treatment, your doctor will need to make regular checks on your progress to ensure that you are reacting properly to the treatment. The doctor will also check for the occurrence of unwanted side effects.

You should not have any immunizations or vaccinations during the use of fluorouracil. This is because your body will have a lower level of resistance than normal and you may be at risk of developing the very condition that you are trying to protect yourself against. People in your household should also avoid the oral polio vaccination during your treatment as you can be at risk of contraction where this occurs. If you are exposed to someone who has received this vaccination then you should remain at a distance from them and should consider wearing a face mask during interactions.

Fluorouracil can temporarily lower the white blood cell count in the patient's body and this can greatly increase their risk of suffering from infection. Simple steps should be taken to avoid infection including staying away from infected people and from public interaction wherever possible. Patients should also exercise increased hygiene and should avoid any activities that could lead to cuts, bruises or injury. You should seek advice about this from your doctor and should seek advice on oral hygiene from your dentist too.


Fluorouracil injection can be stored for 2 years or until expiry date. The medication should be stored at 2-8°C.

Once diluted the medication can be stored for up to 24 hours at 2-8°C.

This treatment should never be exposed to temperatures over 25°C.

Fluorouracil should not be refrigerated or frozen.


Fluorouracil is a chemotherapy treatment used to treat a range of different cancers. These include but are not limited to cancers of the rectum, stomach, breast and pancreas.

Fluorouracil can be used alone or in conjunction with other medications in order to attack the development of cancer cells and eventually allow the body to destroy these cells. Fluorouracil will, however, also attack the development of healthy cells and as such will expose the patient to a significant risk of side effects occurring. Hair loss is common from the use of this treatment and other serious side effects can also occur. Patients should be alert to the fact that side effects may continue to occur for months or even years after the cessation of treatment.

Fluorouracil is an injected medication that will be administered under the supervision of a doctor and may be given at different intervals depending on your condition and your reaction to the medication.

The use of fluorouracil will lower the count of white blood cells in the body and will expose the patient to a greater risk of infection during use. Patients will need to take steps to protect themselves from infection during treatment to avoid further complications.