Sounds like 'le-floo-no-mide'

Leflunomide is used to treat inflammatory conditions such as rheumatoid arthritis and psoriatic arthritis. Find out how to take it safely and possible side effects. Leflunomide is also called Arava.

What is leflunomide?

Leflunomide is an immunosuppressant medicine, which means it weakens your body’s defence (immune) response. Leflunomide is used to treat inflammatory conditions such as rheumatoid arthritis and psoriatic arthritis. 

Leflunomide belongs to a group of medicines called disease-modifying anti-rheumatic drugs (DMARDs). It slows down the disease and its effects on your joints, can help reduce pain and swelling (inflammation) in the joints, and prevent long-term damage caused by joint inflammation.


In Aotearoa New Zealand leflunomide is available as tablets (10 mg and 20 mg).

  • The dose of leflunomide is different for different people, depending on your condition and response to treatment.
  • Always take leflunomide exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much to take, how often to take it and any special instructions.

How to take leflunomide

  • Try to take your dose at the same time each day. You can take leflunomide with or without food.
  • Swallow your tablets whole with a drink of water. Do not break, chew or crush the tablets.
  • If you forget to take your leflunomide dose, take it as soon as you remember. But if it is nearly time for your next dose, take the next dose at the right time. Do not take double the dose.
  • Keep taking leflunomide regularly. Leflunomide does not work straight away. It usually takes a few weeks or months before you notice the full benefits.

Things to consider while you are taking leflunomide

  • Avoid or limit alcohol while you are taking leflunomide. Alcohol increases your risk of side effects such as liver problems. 
  • You will need to have regular blood tests to monitor for side effects and to check whether the treatment is effective. Blood tests are very important during the first few months of treatment.
  • Leflunomide weakens your body’s defence (immune) system, so you are more likely to get infections. It's important to avoid anyone who has chickenpox or shingles.
  • It's important to avoid becoming pregnant while you are taking leflunomide and for some time after you have stopped taking it. Talk to your healthcare provider about which types of contraception are suitable for you. Let your doctor know if you are thinking about becoming pregnant.
  • Some vaccines should not be taken if you are on leflunomide. Always check with your doctor or pharmacist first. It is safe for you to have the annual flu vaccine.
  • Leflunomide may interact with some other medicines and herbal supplements, so check with your doctor or pharmacist before starting leflunomide or before starting any new medicines, including those you may buy over the counter.

Possible side effects 

Like all medicines, leflunomide can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine.

Side effects What should I do?
  • Feeling sick (nausea)
  • Vomiting (being sick)
  • Diarrhoea (runny poo)  
  • This is quite common when you first start taking leflunomide.
  • Tell your doctor if these bother you.
  • Severe skin rash, skin peeling or blisters
  • Stop taking leflunomide and see your doctor immediately.
  • Tingling in the hands and feet 
  • Hair loss
  • Tell your doctor.
  • Signs of getting an infection, such as feeling unwell, fever or chills  
  • Tell your doctor immediately or phone Healthline on 0800 611 116.
  • Signs of changes in your blood cells, such as a severe sore throat, mouth ulcers, easy bruising, nosebleeds, bleeding gums, shortness of breath or fever
  • Tell your doctor immediately as you may need a blood test.
  • Signs of problems with your liver, such as sudden pains in your stomach, loss of appetite or yellowing of your skin and eyes
  • Tell you doctor immediately or phone Healthline on 0800 611 116.
For more information on side effects, see the Medsafe consumer information leaflets Azamun and Imuran.

Did you know that you can report a side effect to a medicine to CARM (Centre for Adverse Reactions Monitoring)? Report a side effect to a product.

Learn more

Arava Consumer Information Sheet, Medsafe, NZ
Leflunomide NZ Formulary Patient Information
Leflunomide Arthritis Australia
Leflunomide RheumInfo


  1. Leflunomide NZ Formulary
Credits: Sandra Ponen, Pharmacist. Reviewed By: Angela Lambie, Pharmacist, Auckland Last reviewed: 08 Nov 2022