5 Fluorouracil / Folinic acid (Mayo)

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Your doctor has explained that you have colorectal cancer and has recommended treatment with chemotherapy.

The chemotherapy drug you are going to have is called 5 Fluorouracil (5FU).  This is given  together with a drug called Folinic Acid (FA) which increases the effectiveness of the 5FU in killing cancer cells. Both drugs are given by injection into a vein in your arm every day for 5 working days. This is repeated every 28 days and represents one cycle. The number of cycles you will receive will be explained to you by your doctor.

You will have a blood test before starting chemotherapy and during treatment. If your blood count is low, chemotherapy may be delayed.

The side-effects described below will not affect everyone. We have outlined those that you may experience during treatment. Your clinic staff will usually work  with you to keep your side-effects to a minimum. It is important that you feel free to ask questions so that you understand what is happening, what to do and what to expect. You should also receive additional information instructing you on what to do if you feel unwell including who to contact and their telephone numbers. Occasionally people have rare side-effects which are not expected or mentioned on this sheet. If in doubt ask!

Side effects

5FU/FA is usually well tolerated with few side-effects. The main potential side-effects are diarrhoea or a sore mouth but these are usually mild and only occur in some people.

Nausea & sickness; Despite the anti-sickness medication given with your chemotherapy and for a few days afterwards, some nausea may occur. This is usually associated with reduced appetite and in some cases vomiting. If marked you should contact the cancer unit for help as its important you do not get dehydrated. Some cancer units prescribe anti-sickness suppository to take home and should be used if sickness occurs. In general, anti-sickness tablets should be taken regularly and are usually successful, but if you do have problems, different  tablets can be prescribed for the next cycle. Some self help tips may also be useful.

If your blood count falls you may experience the following:

• White Blood Cells (WBC). Shivering or shaking attacks of fever. If you feel hot or unwell check your temperature.  If it is 38°C (100F) telephone the Hospital and they will advise you. Do not take Paracetamol or Aspirin if you have a temperature.  A raised temperature indicates infection which could be life threatening. If you have a temperature or feel unwell contact your hospital immediately.
  

• Haemoglobin (Hb) Tiredness, lethargy, breathlessness, dizziness (particularly on standing) and pale facial colour. Occasionally patients require a blood transfusion. 
  

• Platelets If you notice any bleeding, i.e. nose bleeds, unexplained bleeding, bruising or persistent headaches contact the Hospital immediately.

Other advice on paracetamol; As mentioned above, if you have a temperature and feel unwell you may have an infection and may need treatment in hospital, we advise not to take paracetamol in this situation as it may mask your temperature, give false reassurance and delay you presenting to hospital for treatment. Taking paracetamol can otherwise be used with discretion. If for example you have a headache or a mild pain but are otherwise feel well and your temperature is normal paracetamol can be used provided you check your temperature before each dose and allow a full six hours before each administration.

Weight gain; Over the entire course of chemotherapy many patients complain of weight gain. This is caused by a combination of the steroids increasing the appetite, the fatigue causing lack of mobility and the mild nausea often encouraging to nibble rather than eating correct meals - In order to prevent this we recommend regular light exercise and be aware of your dietary intake. 

Weight loss may also be experienced by some patients during their course of chemotherapy , in these cases dietary advice should be sought.

Hair loss; This chemotherapy may cause mild hair loss. It usually starts 3-4 weeks after the first course. You may also experience thinning and loss of eyelashes, eyebrows and other body hair. This is temporary and your hair will regrow after treatment, although it may at first be a different texture, very like a baby's hair. Some departments use a cold cap system to minimise hair loss. Your clinic nurse can arrange for you to have a wig before your treatment starts (NHS prescription charge, prices are approximately £55 for an acrylic wig, £140 for half real hair wig and  £205 for a full real hair wig).  

Sore mouth; You may have a sore mouth after chemotherapy and it is important that you maintain good oral hygiene. A soft, baby toothbrush and a mouthwash may help. If you develop mouth ulcers you must contact your clinic and they will prescribe special mouthwashes to help.  

Fatigue; All chemotherapy can cause fatigue. As your treatment progresses you will experience this. You may find that gentle exercise such as a short walk each day (if you are not working) may help.  Fatigue and malaise may last up to 2-3 months (or longer) after the end of chemotherapy.  

Diarrhoea; This chemotherapy can cause diarrhoea, which can be easily controlled with medicine, but you should inform your doctor if it is severe or continues. It is important to drink plenty of fluids if you do get diarrhoea. If you have any alteration in bowel pattern tell your doctor.  

Fertility may be affected by chemotherapy, in both men and women.  It is important to discuss fertility with your doctor before starting treatment.  For pre-menopausal women, chemotherapy may affect  your periods. They may become heavier, lighter or may stop. In some women this may be permanent, causing menopausal symptoms.You should not become pregnant during chemotherapy, as it will damage a growing baby. You should still take contraceptive precautions even if your periods have stopped, as you could still become pregnant.  Men must also use a barrier contraceptive whilst receiving chemotherapy as sperm is damaged  by chemotherapy.

Steroids; This chemotherapy is given with steroids (e.g. Dexamethasone) to help prevent sickness. Steroids have some side effects, including fluid retention, weight gain, wakefulness and sometimes agitation. If you suffer from  indigestion you may be given tablets to prevent this. If patients are prone to "spots" or acne this can be made worse. Likewise they can temporarily upset diabetes or high blood pressure.

Sensitive eyes; You may find your eyes become more sensitive to the light and that they start "watering". If this occurs your clinic may prescribe you some eye drops.

Sore skin; 5FU can cause soreness of the skin on the palms of the hands and soles of the feet, which can be relieved by vitamin tablets (Pyridoxine). If this occurs you must mention it to your doctor.

Your veins
Three types of damage can occur, listed in order of seriousness:

• You may experience darkening of the veins in your hands and arms. This is normal, usually doesn't hurt and should fade once your course of treatment has been completed

• Towards the end of your chemotherapy course, some veins may feel hard and 'cord-like'. In these veins the blood has clotted (superficial thrombosis) which may take several months to resolve. Your doctor may recommend a low dose of aspirin (ask before taking it yourself).

• These chemotherapy drugs can cause irritation and tissue damage if they leak out of the vein whilst injected. This is called extravasation. All nurses who administer chemotherapy have completed an intensive training programme and are fully aware of what to do if extravasation occurs. Rarely problems can start after you have left the Hospital. Look out for pain, stinging or burning sensations, redness or swelling around the area where the chemotherapy was given. If you notice any of these symptoms after you have left the Hospital, contact the emergency numbers you have been given. In the meantime, keep the arm raised and place a cool (not ice) pack on the area.

Sore eyes; The front of the eyes (cornea) can occasionally feel dry and sticky, especially first thing in the morning. This usually comes on later in the course and can cause some redness and discomfort. Eye drops such artificial tears can be bought over the counter or prescribed by your medical team. 

Nails; The grow of the nails can be impaired by chemotherapy. The amount of damage can vary but in most case there will be some slight discolouration and indentation seen in ridges across the nail beds - a bit like the rings of a tree, each representing an individual chemotherapy cycle. Occasionally the damage can be more troublesome, causing pain and breakdown of the nail bed causing it to lift and separate, possibly even leading to a total loss of the nail. Eventually after chemotherapy has finished the nail will grow back normally.

Further general information Your doctors and specialist nurses are in an ideal position to give you relevant information on your disease and treatment as they know your individual circumstances. Cancerbackup has a help line (0808 800 1234) and a prize winning video available in English, Italian, Urdu, Bengali, Gujarati & Hindi explaining Radiotherapy & Chemotherapy. Cancernet.co.uk has over 500 pages describing cancer, its management, practical tips and tool which patients, their carers and their doctors have found helpful during the cancer journey.