Pemetrexed is a type of chemotherapy. It is also known as Alimta. You might have it as a treatment for:
- pleural mesothelioma (cancer of the outer covering of the lungs)
- non small cell lung cancer (NSCLC)
For NSCLC, you might have pemetrexed on its own or in combination with other cancer drugs such as cisplatin, carboplatin or pembrolizumab.
How does pemetrexed work?
Pemetrexed is a type of drug known as an anti metabolite. It stops cancer cells making and repairing DNA so they can't grow and multiply.
How do you have pemetrexed?
You have pemetrexed as a drip into your bloodstream (intravenously).
You might have treatment through a long plastic tube that goes into a large vein in your chest. The tube stays in place throughout the course of treatment. This can be a:
- central line
- PICC line
If you don't have a central line
You might have treatment through a thin short tube (a cannula) that goes into a vein in your arm each time you have treatment.
How often do you have pemetrexed?
You usually have pemetrexed every 3 weeks. Each treatment takes about 10 minutes.
Pemetrexed blocks the action of folic acid in the body. To help reduce the side effects this can cause, you might have:
- folic acid tablets for around 5 days before treatment and for 21 days (3 weeks) after treatment
- a vitamin B12 injection in the week before you start treatment and then every 9 weeks
You may also take corticosteroids such as dexamethasone the day before treatment starts and for 3 to 5 days each time you have pemetrexed. This is to help lower the chance of getting any skin problems.
You have blood tests before and during your treatment. They check your levels of blood cells and other substances in the blood. They also check how well your liver and kidneys are working.
What are the side effects of pemetrexed?
How often and how severe the side effects are can vary from person to person. They also depend on what other treatments you're having. For example, your side effects could be worse if you're also having other drugs or radiotherapy.
When to contact your team
Your doctor, nurse or pharmacist will go through the possible side effects. They will monitor you closely during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:
- you have severe side effects
- your side effects aren’t getting any better
- your side effects are getting worse
Early treatment can help manage side effects better.
We haven't listed all the side effects here. Remember it is very unlikely that you will have all of these side effects, but you might have some of them at the same time.
Common side effects
These side effects happen in more than 10 in 100 people (more than 10%). You might have one or more of them. They include:
Risk of infection
Increased risk of getting an infection is due to a drop in white blood cells. Symptoms include a change in temperature, aching muscles, headaches, feeling cold and shivery and generally unwell. You might have other symptoms depending on where the infection is.
Infections can sometimes be life threatening. You should contact your advice line urgently if you think you have an infection.
Breathlessness and looking pale
You might be breathless and look pale due to a drop in red blood cells. This is called anaemia.
Diarrhoea or constipation
Tell your doctor or nurse if you have diarrhoea or constipation. They can give you medicine to help.
Feeling or being sick
Feeling or being sick is usually well controlled with anti sickness medicines. Avoiding fatty or fried foods, eating small meals and snacks, drinking plenty of water, and relaxation techniques can all help.
It is important to take anti sickness medicines as prescribed even if you don’t feel sick. It is easier to prevent sickness rather than treating it once it has started.
Mouth sores and ulcers
Mouth sores and ulcers can be painful. It helps to keep your mouth and teeth clean, drink plenty of fluids, avoid acidic foods such as oranges, lemons and grapefruits, and chew gum to keep the mouth moist. Tell your doctor or nurse if you have ulcers.
Loss of appetite
You might lose your appetite for various reasons when you are having cancer treatment. Sickness, taste changes or tiredness can put you off food and drinks.
You might feel very tired and as though you lack energy.
Various things can help you to reduce tiredness and cope with it, for example exercise. Some research has shown that taking gentle exercise can give you more energy. It is important to balance exercise with resting.
Skin problems include a skin rash, dry skin and itching. This usually goes back to normal when your treatment finishes. Your nurse will tell you what products you can use on your skin to help.
To reduce the skin rash your nurse might give you corticosteroids. You usually take them on the day before treatment, the day of treatment, and the day afterwards.
Numbness or tingling in fingers and toes
Numbness or tingling in fingers or toes is often temporary and can improve after you finish treatment. Tell your doctor if you're finding it difficult to walk or complete fiddly tasks such as doing up buttons.
To help prevent kidney damage, it is important to drink plenty of water. You might also have fluids into your vein before, during and after treatment. You have blood tests before your treatments to check how well your kidneys are working.
Sore throat (pharyngitis)
You might get a sore, scratchy, dry throat as the tissues can become inflamed.
Occasional side effects
These side effects happen in between 1 and 10 out of every 100 people (between 1 and 10%). You might have one or more of them. They include:
- an allergic reaction that can cause a skin rash, burning or a prickling sensation
- bruising, nosebleeds or bleeding caused by a drop in platelets in your blood
- hair loss or hair thinning
- high temperature (fever)
- loss of fluid (dehydration) that can make you feel thirsty and have dark yellow and strong smelling urine
- pain in your chest and tummy (abdomen)
- inflammation of the eyes and watery eyes (conjunctivitis), dry eyes, swollen eyelids, excess tears
- taste changes that can make you go off certain foods
- indigestion symptoms including heartburn, bloating and burping
- liver changes that are usually mild and unlikely to cause symptoms
- changes in the way your heart works - you may have changes to your heart beat, feel dizzy, have shortness of breath or chest pain - contact your advice line if you have this. Rarely your heart might stop beating (heart attack)
- a build up of fluid in your body (oedema)
Rare side effects
These side effects happen in fewer than 1 in 100 people (fewer than 1%). You might have one or more of them. They include:
- inflammation of the lining of the bowel (colitis) which can cause bleeding when you have pemetrexed with another drug called cisplatin
- scarring on the air sacs of your lungs which can cause a dry cough, chest pain and shortness of breath
- blood clots that can be life threatening; signs are pain, redness and swelling where the clot is. Feeling breathless can be a sign of a blood clot in the lung. Contact your advice line or doctor straight away if you have any of these symptoms
- a swollen liver which might cause pain in the tummy, nausea or feeling full. You will have tests to check your liver function
- pain, coldness and paleness in your hands and feet
- a severe skin reaction that may start as tender red patches which leads to peeling or blistering of the skin. You might also feel feverish and your eyes may be more sensitive to light. This is serious and could be life threatening
- reduced blood flow to your limbs
- a stroke or a bleed in the brain
- lung changes such as shortness of breath if you are having or had radiotherapy to the lungs (radiation pneumonitis) or tightness of the chest and wheezing
- bleeding from the back passage (rectum)
- bleeding in the bowel or stomach
- sore, inflamed skin in the food pipe (oesophagus)
Coping with side effects
We have more information about side effects and tips on how to cope with them.
What else do I need to know
Other medicines, foods and drinks
Cancer drugs can interact with some other medicines and herbal products. Tell your doctor or pharmacist about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies.
You should avoid taking ibuprofen from 5 days before and up until 2 days after pemetrexed. Ibuprofen can make the pemetrexed side effects worse.
This drug contains sodium (salt). You might need to take account of this if you are on a controlled sodium diet. Tell your doctor if you are on a low salt diet.
Pregnancy and contraception
This treatment may harm a baby developing in the womb. It is important not to become pregnant or father a child while you're having treatment and for at least 6 months afterwards. Talk to your doctor or nurse about effective contraception before starting treatment.
Loss of fertility
You may not be able to become pregnant or father a child after treatment with this drug. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.
Men might be able to store sperm before starting treatment. And women might be able to store eggs or ovarian tissue. But these services are not available in every hospital, so you would need to ask your doctor about this.
Don’t breastfeed during this treatment because the drug may come through into your breast milk.
Treatment for other conditions
Always tell other doctors, nurses, pharmacists or dentists that you’re having this treatment if you need treatment for anything else, including teeth problems.
Don’t have immunisations with live vaccines while you’re having treatment and for up to 12 months afterwards. The length of time depends on the treatment you are having. Ask your doctor or pharmacist how long you should avoid live vaccinations.
In the UK, live vaccines include rubella, mumps, measles, BCG, yellow fever and one of the shingles vaccines called Zostavax.
You can have:
- other vaccines, but they might not give you as much protection as usual
- the flu vaccine (as an injection)
- the coronavirus (COVID-19) vaccine - talk to your doctor or pharmacist about the best time to have it in relation to your cancer treatment
Members of your household who are aged 5 years or over are also able to have the COVID-19 vaccine. This is to help lower your risk of getting COVID-19 while having cancer treatment and until your
Contact with others who have had immunisations - You can be in contact with other people who have had live vaccines as injections. Avoid close contact with people who have recently had live vaccines taken by mouth (oral vaccines) such as the oral typhoid vaccine.
If your immune system is severely weakened, you should avoid contact with children who have had the flu vaccine as a nasal spray as this is a live vaccine. This is for 2 weeks following their vaccination.
Babies have the live rotavirus vaccine. The virus is in the baby’s poo for about 2 weeks and could make you ill if your immunity is low. Get someone else to change their nappies during this time if you can. If this isn't possible, wash your hands well after changing their nappy.
More information about this treatment
For further information about this treatment go to the electronic Medicines Compendium (eMC) website.
You can report any side effect you have to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.