Generic name: Fluorouracil
Trade name: Adrucil®
Other names: 5-Fluorouracil
Chemocare.com uses generic names in all descriptions of drugs. Adrucil is the trade
name for Fluorouracil. 5-fluorouracil and 5-FU are other names for Fluorouracil.
In some cases, health care professionals may use the trade name Adrucil or other
names 5-fluorouracil and 5-FU when referring to the generic drug name Fluorouracil.
Drug type: 5-FU is an anti-cancer ("antineoplastic" or "cytotoxic")
chemotherapy drug. This medication is classified as an "antimetabolite."
(For more detail, see "How this drug works" section below).
What 5-FU is used for:
- Colon and rectal cancer.
- Breast cancer.
- Gastrointestinal cancers including: anal, esphageal, pancreas and gastric (stomach).
- Head and neck cancer
* Hepatoma (liver cancer).
- Ovarian cancer.
- Topical use (cream or solution) in basal cell cancer of the skin and actinic keratoses.
-see document fluorouracil(cream).
Note: If a drug has been approved for one use, physicians
may elect to use this same drug for other problems if they believe it may be helpful.
How 5-FU is given:
- As an injection into the vein (intravenous or IV), or as an infusion. The
amount of time and schedule of infusion varies depending on a specific protocol,
it may be given over several hours to several weeks.
- As a topical ointment, a thin coating is applied to the affected skin lesions twice
a day, treatment may continue over several weeks. (see document fluorouracil(cream).
- The amount of 5-FU that you will receive depends on many factors, including your
height and weight, your general health or other health problems, and the type of
cancer or condition being treated. Your doctor will determine your dose and
Side effects of 5-FU:
Important things to remember about the side effects of 5-FU:
- Most people do not experience all of the side effects listed.
- Side effects are often predictable in terms of their onset and duration.
- Side effects are almost always reversible and will go away after treatment is complete.
- There are many options to help minimize or prevent side effects.
- There is no relationship between the presence or severity of side effects and the
effectiveness of the medication.
- The side effects of 5-FU and their severity depend a variety of factors including
dosage, the individual's metabolism, other drugs given as part of a combination
therapy, and/or the schedule and duration of treatment.
The following side effects are common (occurring in greater than 30%) for
patients taking 5-FU:
- Nausea and possible occasional vomiting.
- Mouth sores.
- Poor appetite.
- Watery eyes, sensitivity to light (photophobia) (see eye problems).
- Taste changes, metallic taste in mouth during infusion.
- Discoloration along vein through which the medication is given.
- Low blood counts. Your white and red blood cells and platelets may temporarily
decrease. This can put you at increased risk for infection, anemia and/or
Nadir: Meaning low point, nadir is the point in time between chemotherapy
cycles in which you experience low blood counts.
Onset: 7-10 days
Nadir: 9-14 days
Recovery: 21-28 days
These side effects are less common side effects (occurring in about 10-29%)
of patients receiving 5-FU:
- Skin reactions: Dry, cracking, peeling skin. Darkening of the skin (hyperpigmentation),
darkening of the skin where previous radiation treatment has been given (radiation
- Hair thinning.
- Nail changes - discoloration, loss of nails (rare)(see skin reactions).
- Hand -foot syndrome (Palmar-plantar erythrodysesthesia or PPE) -skin rash, swelling,
redness, pain and/or peeling of the skin on the palms of hands and soles of feet.
Usually mild, starting 5-6 weeks after start of treatment. May require reductions
in the dose of the medication.
Serious adverse reactions to 5-FU are; chest pain, EKG changes and increases
in cardiac enzymes - which may indicate problems with the heart. These symptoms
are very rare but increased for patients with a prior history of heart disease.
Not all side effects are listed above. Some that are rare (occurring in less than
10% of patients) are not listed here. However, you should always inform your
health care provider if you experience any unusual symptoms.
When to contact your doctor or health care provider:
Contact your health care provider immediately, day or night, if you
should experience any of the following symptoms:
- Fever of 100.5° F (38° C) or higher, chills (possible signs of infection)
The following symptoms require medical attention, but are not an emergency.
Contact your health care provider within 24 hours of noticing any of the
- Nausea (interferes with ability to eat and unrelieved with prescribed medication)
- Vomiting (vomiting more than 4-5 times in a 24 hour period)
- Diarrhea (4-6 episodes in a 24-hour period) despite anti-diarrhea medication and
- Unusual bleeding or bruising
- Black or tarry stools, or blood in your stools or urine
- Extreme fatigue (unable to carry on self-care activities)
- Mouth sores (painful redness, swelling or ulcers)
- Tingling or burning, redness, swelling of the palms of the hands or soles of feet
Always inform your health care provider if you experience any unusual symptoms.
- Before starting 5-FU treatment, make sure you tell your doctor about any other medications
you are taking (including prescription, over-the-counter, vitamins, herbal remedies,
- Do not receive any kind of immunization or vaccination without your doctor's approval
while taking 5-FU.
- Inform your health care professional if you are pregnant or may be pregnant prior
to starting this treatment. Pregnancy category D (5-FU may be hazardous to the fetus.
Women who are pregnant or become pregnant must be advised of the potential hazard
to the fetus). For both men and women: Do not conceive a child (get pregnant) while
taking 5-FU. Barrier methods of contraception, such as condoms, are recommended.
Discuss with your doctor when you may safely become pregnant or conceive a child
- Do not breast feed while taking this medication.
- Use of ice chips in the mouth 10-15minutes before and after IV injections of 5-FU
may reduce the incidence and severity of mouth sores.
- To help treat/prevent mouth sores, use a soft toothbrush, and rinse three times
a day with 1/2 to 1 teaspoon of baking soda and/or 1/2 to 1 teaspoon of salt mixed
with 8 ounces of water.
- Drink at least two to three quarts of fluid every 24 hours, unless you are instructed
- Follow regimen of anti-diarrhea medication as prescribed by your health care professional.
- Eat foods that may help reduce diarrhea (see
managing side effects - diarrhea).
- You may be at risk of infection so try to avoid crowds or people with colds and/or
not feeling well, and report fever or any other signs of infection immediately to
your health care provider.
- Wash your hands often.
- To reduce nausea, take anti-nausea medications as prescribed by your doctor, and
eat small, frequent meals.
- Avoid sun exposure. Wear SPF 15 (or higher) sunblock and protective clothing.
- Prevention of hand-foot syndrome. Modification of normal activities of daily living
to reduce friction and heat exposure to hands and feet, for about a week after treatment.
(for more information see - Managing side effects: hand foot syndrome).
- Keep palms of hands and soles of feet moist using emollients.
- You may experience drowsiness or dizziness; avoid driving or engaging in tasks that
require alertness until your response to the drug is known.
- In general, drinking alcoholic beverages should be kept to a minimum or avoided
completely. You should discuss this with your doctor.
- Get plenty of rest.
- Maintain good nutrition.
- If you experience symptoms or side effects, be sure to discuss them with your health
care team. They can prescribe medications and/or offer other suggestions that
are effective in managing such problems.
Monitoring and testing:
You will be checked regularly by your health care professional while you are taking
5-FU, to monitor side effects and check your response to therapy. Periodic
blood work to monitor your complete blood count (CBC) as well as the function of
other organs (such as your kidneys and liver) will also be ordered.
How 5-FU works:
Cancerous tumors are characterized by cell division, which is no longer controlled
as it is in normal tissue. "Normal" cells stop dividing when they come
into contact with like cells, a mechanism known as contact inhibition. Cancerous
cells lose this ability. Cancer cells no longer have the normal checks and
balances in place that control and limit cell division. The process of cell
division, whether normal or cancerous cells, is through the cell cycle. The
cell cycle goes from the resting phase, through active growing phases, and then
to mitosis (division).
The ability of chemotherapy to kill cancer cells depends on its ability to halt
cell division. Usually, the drugs work by damaging the RNA or DNA that tells
the cell how to copy itself in division. If the cells are unable to divide,
they die. The faster the cells are dividing, the more likely it is that chemotherapy
will kill the cells, causing the tumor to shrink. They also induce cell suicide
(self-death or apoptosis).
Chemotherapy drugs that affect cells only when they are dividing are called cell-cycle
specific. Chemotherapy drugs that affect cells when they are at rest are called
cell-cycle non-specific. The scheduling of chemotherapy is set based on the
type of cells, rate at which they divide, and the time at which a given drug is
likely to be effective. This is why chemotherapy is typically given in cycles.
Chemotherapy is most effective at killing cells that are rapidly dividing.
Unfortunately, chemotherapy does not know the difference between the cancerous cells
and the normal cells. The "normal" cells will grow back and be healthy but in the
meantime, side effects occur. The "normal" cells most commonly affected by
chemotherapy are the blood cells, the cells in the mouth, stomach and bowel, and
the hair follicles; resulting in low blood counts, mouth sores, nausea, diarrhea,
and/or hair loss. Different drugs may affect different parts of the body.
5-FU belongs to the category of chemotherapy called antimetabolites. Antimetabolites
are very similar to normal substances within the cell. When the cells incorporate
these substances into the cellular metabolism, they are unable to divide.
Antimetabolites are cell-cycle specific. They attack cells at very specific
phases in the cycle. Antimetabolites are classified according to the substances
with which they interfere.
- Folic acid antagonist: Methotrexate
- Pyrimidine antagonist: 5-Fluorouracil, Foxuridine, Cytarabine,
Capecitabine, and Gemcitabine
- Purine antagonist: 6-Mercaptopurine and 6-Thioguanine
- Adenosine deaminase inhibitor: Cladribine, Fludarabine and Pentostatin
Note: We strongly encourage you to talk with your health
care professional about your specific medical condition and treatments. The information
contained in this website is meant to be helpful and educational, but is not a substitute
for medical advice.