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Leflunomide tablets for arthritis


Leflunomide is prescribed by specialist doctors.

It may take several weeks before you start to feel the benefit of the treatment. This is normal.

Do not drink alcohol whilst you are taking leflunomide - it will increase the risk of damage to your liver.

Leflunomide can harm an unborn baby - use suitable contraception so that you do not become pregnant or father a child.

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About leflunomide

Type of medicine

A disease-modifying antirheumatic medicine

Used for

Rheumatoid arthritis; psoriatic arthritis

Also called


Available as


Arthritis means inflammation of joints. Rheumatoid arthritis (RA) is a common form of arthritis.It is thought to be an autoimmune disease. The immune system normally makes small proteins (antibodies) to attack bacteria, viruses and other germs. In people with autoimmune diseases, the immune system makes antibodies against tissues of the body. In people with RA, antibodies are formed against the tissues that surround the joints. This causes inflammation, pain, and swelling around the affected joints. Over time, it causes damage. Medicines called disease-modifying antirheumatic drugs (DMARDs) are prescribed to suppress the inflammation.

Psoriatic arthritis is a particular type of arthritis that develops in some people who also have a skin condition called psoriasis.

Leflunomide is a DMARD. It eases pain and stiffness associated with both of the conditions mentioned above, and it also reduces the damaging effect of the disease on joints. It is thought to work by blocking the way inflammation develops in joints.

Before taking leflunomide

Some medicines are not suitable for people with certain conditions, and sometimes a medicine can only be used if extra care is taken. For these reasons, before you start taking leflunomide it is important that your doctor knows:

  • If you are pregnant, trying for a baby or breastfeeding.

  • If you have any problems with the way your liver works, or if you have any problems with the way your kidneys work.

  • If you currently have an infection, or if you have ever had tuberculosis (TB).

  • If you have been told by a doctor that you have low numbers of proteins in your blood.

  • If you know you have a blood or bone marrow disorder.

  • If you have a problem which affects your immune system, such as AIDS.

  • If you have ever had an allergic reaction to a medicine.

  • If you are taking any other medicines. This includes any medicines which are available to buy without a prescription, as well as herbal and complementary medicines.

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How to take leflunomide

  • Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about leflunomide and how to take it, and it will also provide you with a full list of the side-effects which you could experience

  • If you have recently taken another DMARD, your doctor will want to make sure that all of this medicine has gone from your bloodstream before you start taking leflunomide. This is called a washout procedure. It is important that you follow any directions that you are given to do this.

  • Take leflunomide exactly as your doctor tells you to. It is taken once a day. Your doctor will prescribe a high-strength (100 mg) tablet for the first three days. After this, the strength of your tablets will be reduced to 10 mg or 20 mg, and you will stay on this lower dose.

  • Swallow the tablet with a drink of water. You can take leflunomide either with or without food. Swallow the tablet whole - do not chew or break it.

  • Try to take leflunomide at the same time of day each day, as this will help you to remember to take it regularly, every day. If you forget to take a dose, take it as soon as you remember. If you do not remember until the following day, leave out the forgotten dose from the previous day and take the dose that is due as normal. Do not take two doses at the same time to make up for a missed dose.

Getting the most from your treatment

  • Try to keep your regular appointments with your doctor. This is so your doctor can check on your progress. Your doctor will want you to have some blood tests before and during the treatment.

  • Leflunomide may have no immediate effect on pain or inflammation. It can take several weeks before you notice any effect, and several months before you notice the full benefit. It is, however, important that you keep taking it as prescribed, even if it does not seem to be working at first.

  • Your doctor will recommend that you do not drink alcohol while you are on leflunomide. This is because it can increase the risk of side-effects, such as liver problems.

  • This medicine can harm an unborn baby:

    • If you are female, you must not get pregnant while you are taking leflunomide and for at least two years afterwards. Make sure you have discussed with your doctor what contraception is suitable for you and your partner. If you wish to have a baby after finishing treatment, you should discuss this with your doctor, as the medicine continues in your bloodstream for up to two years.

    • If you are male you must not get a woman pregnant while you are taking leflunomide and for at least three months afterwards. Ask your doctor about suitable contraception. If you wish to become a father, you should discuss this with your doctor. It is important that it is confirmed that leflunomide has been sufficiently removed from your body before you father a child.

  • Your doctor will discuss with you the possibility of unwanted side-effects, such as that you could become more susceptible to infections. Also, that there is a slightly increased risk of cancer associated with this medicine. If you have any concerns about your general health, discuss these with your doctor straightaway.

  • While you are taking leflunomide, do not have any immunisations (vaccinations) without talking to your doctor first. Leflunomide lowers your body's resistance and there is a chance that you may get an infection from the vaccine. Also, some vaccines may be less effective.

  • Before you have any kind of medical treatment, tell the doctor, dentist or surgeon that you are taking leflunomide.

  • Treatment with leflunomide is usually long-term unless you experience an adverse effect. Continue to take the tablets unless you are advised otherwise.

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Can leflunomide cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with leflunomide. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.


leflunomide side-effects

(these affect fewer than 1 in 10 people)

What can I do if I experience this?

Increased susceptibility to infections

Contact your doctor if you feel unwell


Drink plenty of water to replace lost fluids

Feeling sick (nausea) or being sick (vomiting), tummy (abdominal) pain

Stick to simple foods - avoid fatty or spicy meals. Try taking the tablets after food

Feeling dizzy or tired

Do not drive and do not use tools or machines while affected


Drink plenty of water and ask your pharmacist to recommend a suitable painkiller. If the headaches continue, let your doctor know

Increased blood pressure, loss of appetite, mouth ulcers, tingling feelings, tendon inflammation, increased hair loss, itchy skin rash, dry skin

If any of these become troublesome, discuss them with your doctor

If you experience any other symptoms which you think may be due to the tablets, speak with your doctor or pharmacist for further advice.

How to store leflunomide

  • Keep all medicines out of the reach and sight of children.

  • Store in a cool, dry place, away from direct heat and light.

Important information about all medicines

Important information about all medicines

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

If you buy any medicines, check with a pharmacist that they are safe to take with your other medicines.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

Report side effects to a medicine or vaccine

If you experience side effects, you can report them online through the Yellow Card website.

Further reading and references

Article History

The information on this page is written and peer reviewed by qualified clinicians.

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