What is interferon?

Interferon alpha (Roferon-A®) is used to treat:

It is often called interferon for short.

It is best to read this information with our general information about the type of cancer you have.

Interferon is a type of immunotherapy drug called an immune system modulator. Your doctor will talk to you about this treatment and its possible side effects before you agree (consent) to have treatment.

How is interferon given?

Interferon is usually given as an injection under the skin (subcutaneously). You can learn how to give yourself the injections at home, or you may want a relative or carer to learn so they can help you. A district nurse or GP practice nurse can also give them to you. Interferon may be given on its own or in combination with other cancer drugs.

During treatment you usually see a cancer doctor, a cancer nurse or specialist nurse, and a specialist pharmacist. This is who we mean when we mention doctor, nurse or pharmacist in this information.

You will have regular blood tests during your treatment. Interferon can reduce the number of blood cells in your blood. If your blood cell levels get too low your doctor may stop your treatment for a short time until this improves.

Your doctor or nurse will explain how often you take interferon and how long treatment will last.

There are some important things to remember about interferon:

  • If you forget to take your injection, tell your doctor – do not take a double dose.
  • Store it in the fridge and follow any instructions given by your pharmacist.
  • Keep it safe and out of sight and reach of children.
  • If your treatment is stopped, return any unused injections to the pharmacist.

About side effects

We explain the most common side effects of this treatment here. We also include some less common side effects.

You may get some of the side effects we mention, but you are unlikely to get all of them. If you are also having treatment with other cancer drugs, you may have some side effects that we have not listed here. Always tell your doctor, nurse or pharmacist about any side effects you have.

Your doctor can give you drugs to help control some side effects. It is important to take them exactly as your nurse or pharmacist explains. This means they will be more likely to work for you. Your nurse will give you advice about managing your side effects. After your treatment is over, most side effects start to improve.

Serious and life-threatening side effects

Some cancer treatments can cause severe side effects. Rarely, these may be life-threatening. Your cancer doctor or nurse can explain the risk of these side effects to you.

Contact the hospital

Your nurse will give you telephone numbers for the hospital. If you feel unwell or need advice, you can call them at any time of the day or night. Save these numbers in your phone or keep them somewhere safe.

More information

We cannot list every side effect for this treatment. There are some rare side effects that are not listed. You can visit the electronic Medicines Compendium (eMC) for more detailed information.

Common side effects

Flu-like symptoms

These include:

  • a high temperature
  • chills, headaches
  • muscle and joint pains.

You may get these symptoms soon after you start treatment. These symptoms can be quite severe at the start of your treatment with interferon. They usually get less severe during your course of treatment. Your doctor may advise you to take paracetamol to help with them.

Tiredness

Feeling tired is a common side effect. Try to pace yourself and plan your day so you have time to rest. Gentle exercise, like short walks, can give you more energy. If you feel sleepy, do not drive or operate machinery.

Changes to your mood

Some people may have mood changes. These could be:

  • depression
  • anxiety
  • mood swings
  • restlessness
  • difficulty sleeping.

If you feel depressed or have other changes to your mood, it is important to tell your doctor straight away.

Risk of infection

This treatment can reduce the number of white blood cells in your blood. These cells fight infection. If the number of white blood cells is low, you are more likely to get an infection. A low white blood cell count is called neutropenia.

If you have an infection, it is important to treat it as soon as possible. Contact the hospital straight away on the 24-hour contact number you have if:

  • your temperature goes over 37.5°C (99.5°F)
  • you suddenly feel unwell, even with a normal temperature
  • you have symptoms of an infection.

Symptoms of an infection include:

  • feeling shivery
  • a sore throat
  • a cough
  • diarrhoea
  • needing to pass urine often.

It is important to follow any specific advice your cancer treatment team gives you.

You will have regular blood tests during treatment. If your white blood cell count is low, your doctor may reduce or delay your treatment for a short time.

Bruising and bleeding

This treatment can reduce the number of platelets in your blood. Platelets are cells that help the blood to clot. 

Tell your doctor if you have any bruising or bleeding that you cannot explain. This includes:

  • nosebleeds
  • bleeding gums
  • tiny red or purple spots on the skin that may look like a rash.

Some people may need a drip to give them extra platelets. This is called a platelet transfusion.

Feeling sick

Your doctor can give you anti-sickness drugs to help prevent or control sickness. If you still feel sick, contact the hospital as soon as possible. They can give you advice and change the anti-sickness drug to one that works better for you.

Interferon can also cause pain in your tummy (abdomen). If this happens, tell your doctor.

Loss of appetite

This treatment can affect your appetite. Do not worry if you do not eat much for a day or two. But if your appetite does not come back after a few days, tell your nurse or dietitian. They will give you advice. They may give you food or drink supplements.

Redness at the injection site

This can be reduced by having the injections in different places. Your nurse or doctor can give you advice on how to reduce any discomfort. Tell your doctor or nurse straight away if the area becomes red, tender and warm. These can be signs of infection.

Headache

Interferon may cause headaches. If you have headaches more often or they are more severe than usual, tell your doctor or nurse.

Diarrhoea

This treatment may cause diarrhoea. Diarrhoea means passing more stools (poo) than is usual for you, or having watery or loose stools. If you have a stoma, it will be more active than usual.

If you have diarrhoea:

  • try to drink at least 2 litres (3½ pints) of fluids each day
  • avoid alcohol, caffeine, milk products, high-fat foods and high-fibre foods
  • contact the hospital for advice.

Increased sweating

Interferon may make you sweat more. Wearing natural fabrics such as cotton may help.

Hair thinning

Your hair may get thinner during treatment. Rarely, this treatment can cause complete hair loss. Hair usually begins to grow back and thicken a few weeks after treatment ends. 

Effects on the heart

Interferon can affect the way the heart works. You may have tests to see how well your heart is working. These may be done before, during, and sometimes after treatment. If interferon is causing heart problems, your doctor may give you drugs to treat these. Sometimes your doctor will stop the interferon.

Contact a doctor straight away if you:

  • have pain or tightness in your chest
  • feel breathless or dizzy
  • feel your heart is beating too fast or too slowly.

Other conditions can cause these symptoms, but it is important to get them checked by a doctor.

Less common side effects

Allergic reaction

Rarely, some people have an allergic reaction to interferon. Contact the hospital straight away if you develop:

  • red, warm and itchy bumps on the skin (like nettle rash)
  • swelling of the lips, tongue or throat
  • breathlessness, wheezing, a cough or sudden difficulty with breathing
  • a tight chest or chest pain.

Raised blood sugar levels

Interferon may raise your blood sugar levels. Symptoms of this include feeling thirsty, needing to pass urine more often and feeling tired. Tell your doctor or nurse if you have these symptoms.

If you have diabetes, your blood sugar levels may be higher than usual. Your doctor will talk to you about how to manage this.

Effects on the eyes

Interferon can cause eyesight changes. Changes are usually mild, but rarely they can be more severe. You may have eye tests to check your vision before and during your treatment.

If you notice any eye problems or eyesight changes, contact your doctor.

Dry mouth

Interferon can make your mouth dry. If you have any problems with your mouth, tell your nurse or doctor. They can give you treatments to help.

Taste changes

Your sense of taste may change during treatment. Sucking sugar-free sweets may help with this. Some foods may taste different or have no taste. Try different foods to find out what tastes best to you. Taste changes usually get better after treatment finishes. Your nurse can give you more advice.

Skin changes

Your skin may become dry or itchy. Tell your doctor or nurse about any skin changes. They can give you advice and may give you creams or medicines to help.

If you have psoriasis, it may get worse during treatment. Your doctor can tell you more about this.

Effects on the kidneys or liver

In some people, interferon can affect their kidneys or liver. This is usually mild and goes back to normal after treatment. You will have regular blood tests to check your kidneys and liver.

Other information about interferon

Other medicines

Some medicines can affect this treatment or be harmful when you are having it. This includes medicines you can buy in a shop or chemist. Tell your cancer doctor about any drugs you are taking, including vitamins, herbal drugs and complementary therapies.

Vaccinations

Your doctor or nurse may talk to you about vaccinations. These help reduce your risk of getting infections.

Doctors usually recommend that you have a flu jab, which is an inactivated vaccination. People with weak immune systems can have this type of vaccination.

If your immune system is weak, you need to avoid live vaccinations such as shingles. Your cancer doctor or GP can tell you more about live vaccinations.

Driving and using machines

If you have blurred vision, feel drowsy, tired, or have difficulty concentrating, do not drive or use machines.

Fertility

Some cancer drugs can affect whether you can get pregnant or make someone pregnant. If you are worried about this, it is important to talk with your doctor before you start treatment.

Contraception

Your doctor will advise you not to get pregnant or make someone pregnant while having this treatment. The drugs may harm a developing baby. It is important to use contraception during your treatment and for a while after treatment finishes. Your doctor, nurse or pharmacist can tell you more about this.

Breastfeeding

Women are advised not to breastfeed while having this treatment. This is because the drugs could be passed to the baby through breast milk.

Medical and dental treatment

If you need medical treatment for any reason other than cancer, always tell the doctors and nurses that you are having cancer treatment. Give them the contact details for your cancer doctor so they can ask for advice.

If you think you need dental treatment, talk to your cancer doctor or nurse. Always tell your dentist you are having cancer treatment.

How we can help

How to print a PDF from this website
Instructions on how you can make a PDF version of this page using the print function on your browser.
Clinical Information Nurse Specialists
Our Cancer Information Nurse Specialists are dedicated cancer nurses available to talk to on our Macmillan Cancer Support Line. 
0808 808 00 00
7 days a week, 8am - 8pm
Email us
Get in touch via this form
Chat online
7 days a week, 8am - 8pm
Online Community
An anonymous network of people affected by cancer which is free to join. Share experiences, ask questions and talk to people who understand.
Help in your area
What's going on near you? Find out about support groups, where to get information and how to get involved with Macmillan where you live.