How erlotinib works

Erlotinib is a type of targeted therapy drug called a tyrosine kinase inhibitor. Kinases are proteins that help control how cells grow and divide.

Erlotinib blocks (inhibits) signals within the cancer cells and stops the action of a protein called epidermal growth factor receptor (EGFR). Blocking the signals causes the cells to die. This may shrink a cancer or stop it growing for a time.

It is best to read this with our general information about the type of cancer you have. During treatment, you will see a cancer doctor and a cancer nurse. This is who we mean when we mention a doctor or nurse in this information.

When erlotinib is given

Erlotinib may only be available in some situations. Your cancer doctor can tell you if it is appropriate for you. Some people may be given it as part of a clinical trial. If a drug is not available on the NHS, there may be different ways you are still able to have it. Your cancer doctor can give you advice.

Non-small cell lung cancer (NSCLC)

Erlotinib can be used to treat non-small cell lung cancer (NSCLC) that has spread (metastatic cancer).

You may have a test to check if you are likely to benefit from erlotinib. This test is done on samples of cancer cells taken by biopsy or during surgery. Sometimes the test is done when you are first diagnosed with NSCLC. But samples taken during biopsy or surgery are always stored so tests can also be done later if needed.

Pancreatic cancer

Erlotinib can also be used with the chemotherapy drug gemcitabine, to treat people with pancreatic cancer that has spread (metastatic cancer).

Taking erlotinib tablets

You take erlotinib as tablets once a day. Swallow the tablets whole with a glass of water – do not crush or chew them. Take it at the same time every day. You take it at least one hour before or two hours after eating food.

Always take erlotinib exactly as your nurse or pharmacist explained. This is important to make sure it works as well as possible for you.

There are some important things to remember when taking your tablets:

  • If you forget to take a tablet, do not take a double dose. Keep to your regular schedule and tell your doctor or nurse.
  • Keep tablets in the original package and at room temperature, away from heat and direct sunlight.
  • Keep them safe and out of the sight and reach of children.
  • Get a new prescription before you run out of tablets.
  • Make sure you have enough for holidays.
  • Return any unused tablets to the pharmacist if your treatment is stopped.
  • If you are sick just after taking the tablets, contact the hospital. You may need to take another dose.

Possible 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.

Common side effects

Skin changes

You may develop an acne-like rash on the face, neck and body. The skin may also become dry, itchy and flaky.

Always tell your doctor or nurse about any skin changes or if they get any worse. They can give you advice and prescribe creams or medicines to help.

Here are some tips:

  • Wash with tepid water using mild, unperfumed, soap-free cleansers
  • Moisturise your skin regularly with unperfumed moisturisers – ask your doctor or nurse what’s best
  • Don’t use anti-acne products or any products containing alcohol on your skin
  • Wear sunscreen with sun protection factor (SPF) of at least 30 when in the sun, and cover up with clothing or a hat.

Rarely people may have a very severe skin reaction. You must contact the hospital straight away if this happens. The symptoms can include large blisters, peeling skin and sores in your mouth. You may also have a fever (high temperature).

If you have severe skin problems your doctor may lengthen the time in between your treatments or lower the dose.


If you have diarrhoea, contact the hospital for advice. Try to drink at least 2 litres (3½ pints) of fluids every day. It can help to avoid alcohol, caffeine, milk products, high-fat foods and high-fibre foods.

Feeling tired

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.

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 shaky
  • a sore throat
  • a cough
  • diarrhoea
  • needing to pass urine a lot.

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

The number of white blood cells will usually return to normal before your next treatment. You will have a blood test before having more treatment. If your white blood cell count is low, your doctor may delay your treatment for a short time.

Eye problems

Some people develop sore, red eyes (conjunctivitis) or dry eyes while they are being treated with erlotinib. Your doctor can prescribe eye drops to help with this. Tell your doctor if you notice any changes.

Tell your doctor or nurse straight away if you have eyesight changes, or if your eyes become more painful or sensitive to light.

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.

Feeling sick

Your doctor can give you anti-sickness drugs to help prevent or control sickness. If you still feel sick, tell your doctor. They can prescribe other anti-sickness drugs that may work better for you.

Sore mouth

You may get a sore mouth or mouth ulcers. This can make you more likely to get a mouth infection.

Use a soft toothbrush to clean your teeth or dentures in the morning, at night and after meals.

If your mouth is sore:

  • tell your nurse or doctor – they can give you a mouthwash or medicines to help
  • try to drink plenty of fluids
  • avoid alcohol, tobacco, and foods that irritate your mouth.

Mood changes

You may notice that you feel low or have changes in your mood. Talk to your doctor or nurse if you feel like this. It might help to talk to a family member or friend about how you are feeling. We have more information about dealing with emotions.


Erlotinib can cause nosebleeds. These are usually mild and stop without needing treatment. Tell your doctor or nurse if you have nosebleeds.


This treatment may cause headaches. If this happens, tell your doctor or nurse. They can give you painkillers.

Numb or tingling hands or feet (peripheral neuropathy)

This treatment may affect the nerves, which can cause numb, tingling or painful hands or feet. You may find it hard to fasten buttons or do other fiddly tasks. Tell your doctor if you have these symptoms.

Breathing problems

Always tell your doctor if you notice wheezing or a cough, or if you feel short of breath.

If you suddenly become breathless or your breathing gets worse, possibly with a cough or high temperature, tell your doctor immediately. You may have an inflammation of the lungs. This is a rare side effect. Your doctor can tell you more about this.

Less common and rare side effects

Abdominal (tummy) pain

Some people have pain or discomfort in their tummy during treatment with erlotinib. Tell your doctor if this happens to you.

Very rarely, erlotinib can cause a hole (perforation) in the small bowel. Contact your doctor immediately if you have:

  • severe pain in the tummy
  • bleeding from the back passage
  • black stools
  • vomiting up blood (or vomit that looks like coffee grounds).

It is important to tell your doctor straight away if you feel unwell or have any severe side effects, even if they are not mentioned above.

Hair changes

These are less common than skin changes, but sometimes develop after three months or more. Your eyelashes may grow longer and curlier. You may notice that your head and body hair is finer, curlier or more brittle. Some people have hair thinning or hair loss. Hair changes are usually temporary and improve gradually once treatment is over.

Other information


Smoking reduces the level of erlotinib in the blood and may make it less effective. If you smoke, try to quit before you start treatment. Tell your doctor or pharmacist if you stop smoking during treatment.

Other drugs

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


Doctors don’t yet know how this treatment may affect your fertility (the ability to become pregnant or father a child). If you are worried about this, talk to you doctor before treatment starts.


Your doctor will advise you not to get pregnant or make someone pregnant while having this treatment and for some time afterwards. The drugs may harm the developing baby. It is important to use effective contraception.


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 this treatment.

Emergency contacts

It is a good idea to know who you should contact if you have any problems or troublesome side effects when you’re at home. During office hours you can contact the clinic or ward where you had your treatment. Your specialist nurse or doctor will tell you who to contact during the evening or at weekends.

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