Overview: Leflunomide is an oral tablet used for rheumatoid arthritis. This medicine may help reduce joint swelling and damage. Common side effects include diarrhea, nausea, and headaches. Stop this medicine and call your health care provider right away if you get a rash. Also, call your health care provider right away if you have unusual tiredness, stomach pain, a fever, skin ulcer, or unusual bleeding or bruising. Get emergency help if you have trouble breathing or chest pain.
Uses
What is leflunomide used for?
Leflunomide is commonly used for rheumatoid arthritis, a condition where your immune system attacks your joints, causing pain and swelling.
Leflunomide may also be used for other conditions as determined by your health care provider.
How does leflunomide work (mechanism of action)?
Leflunomide blocks an enzyme that helps cells grow and divide. This medicine slows down the growth of some immune cells, which may help reduce swelling and joint damage.
How is leflunomide supplied (dosage forms)?
Brands and other names
- Arava
Dosage forms and strengths
- 10 mg, 20 mg, 100 mg oral tablets
How should I store leflunomide?
Leflunomide should be stored at room temperature, between 68 F and 77 F (20 C and 25 C). It can be exposed to temperatures between 59 F and 86 F (15 C and 30 C) for shorter periods of time, such as when you’re transporting it. Store it in a cool, dry place and protect it from light.
Side Effects
What are the most common side effects of leflunomide?
The most common side effects of leflunomide are listed below. Tell your health care provider if you have any of these side effects that bother you.
- Diarrhea
- Infection in the nose or throat, sore throat, or common cold symptoms
- Nausea
- Headache
- Rash
- Liver damage (see below)
- Upset stomach
There may be other side effects of leflunomide that are not listed here. Contact your health care provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088 (800-332-1088). In Canada, you can report side effects to Health Canada at www.canada.ca/en/health-canada/services/drugs-health-products/medeffect-canada or by calling 866-234-2345.
What are the serious side effects of leflunomide?
While less common, the most serious side effects of leflunomide are described below, along with what to do if they happen.
Liver Damage. Liver damage, also called hepatotoxicity, can happen when taking leflunomide. Keep all appointments to have your blood checked. Call your health care provider right away if you have any of the following symptoms of liver damage.
- Nausea or vomiting
- Stomach or belly pain
- Fever
- Weakness or unusual tiredness
- Itching
- Loss of appetite
- Light-colored poop
- Dark-colored urine (pee)
- Your skin or the whites of your eyes turning yellowish in color
Severe Allergic Reactions. Leflunomide may cause allergic reactions, including a specific type of allergic reaction called DRESS. DRESS stands for drug reaction with eosinophilia and systemic symptoms. It is also sometimes called multi-organ hypersensitivity. This is a reaction that can affect multiple parts of the body including your liver, kidneys, and heart. Stop taking the medicine and get help right away if you have any of the following symptoms of a serious allergic reaction.
- Breathing problems or wheezing
- Racing heart
- Itching or skin rash
- Bumps on the skin called hives that can be red, pink, white, or brown, depending on your skin tone
- Fever or general ill feeling
- Swollen lymph nodes
- Swelling of the face, lips, mouth, tongue, or throat
- Shortness of breath, trouble swallowing, or throat tightness
- Swelling in your feet, ankles, or legs
- Nausea or vomiting
- Dizziness, feeling lightheaded, or fainting
- Stomach cramps
- Joint pain
- Dark-colored pee
- Your skin or the whites of your eyes turning yellowish in color (also called jaundice)
Skin Ulcers. Skin sores (ulcers) may occur when taking leflunomide. Tell your health care provider right away if you have any skin ulcers while taking leflunomide.
Severe Skin Reactions. While rare, some people have had severe skin reactions while taking leflunomide, called Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). If not treated, these reactions can lead to death. If you get a rash, stop taking leflunomide and call your health care provider right away. Get emergency help if you have any of the following symptoms of SJS or TEN.
- Peeling skin that looks burned, red, purple, or discolored
- Painful skin
- Flat rash or blisters on your skin, mouth, nose, and genitals
- Red, painful, watery eyes
- Flu-like symptoms including fever, chills, and muscle aches
Bone Marrow Suppression. Leflunomide may cause your bone marrow to not make enough cells (myelosuppression). This can lead to blood disorders, such as agranulocytosis, low platelet levels (thrombocytopenia), and low white blood cell levels (leukopenia), which can be serious or even life-threatening. Keep all appointments to have your blood checked. Tell your health care provider right away if you have any of the following symptoms of bone marrow suppression.
- Fever
- Shortness of breath
- Pale or yellowish skin
- Easy bruising or bleeding
- Frequent infection
- Unusual weakness or tiredness
- Dizziness, lightheadedness, or feeling like you are about to pass out
- Headache
- Fast or abnormal heartbeat
Infections. Leflunomide can increase your risk of infections, including serious infections. Call your health care provider right away if you have an infection or any of the following symptoms.
- Burning or stinging when you pee
- Coughing, or coughing up blood
- Fever, sweats, chills, or muscle aches
- Shortness of breath
- Diarrhea or stomach pain
- Weight loss
Nerve Problems. Nerves are the fibers that carry sensations from your body to the brain. Damage to these nerves, called peripheral neuropathy, can happen while taking leflunomide. The risk may be higher in people who take certain other medicines, people with diabetes, or those ages 60 and older. Call your health care provider if you develop pain, burning, tingling, numbness, or weakness in your arms, hands, legs, or feet.
Lung Inflammation. Leflunomide can cause inflammation in your lungs, also called interstitial lung disease. This can be serious or even life-threatening. Get emergency help if you have trouble breathing. You may also have a cough, fever, or chest pain.
Warnings & Precautions
Who should not take leflunomide?
Allergies to Ingredients. People who are allergic to any of the following should not take leflunomide.
- Arava
- Leflunomide
- Any of the ingredients in the specific product dispensed
Your pharmacist can tell you all of the ingredients in the specific leflunomide products they stock.
Pregnancy. Do not take leflunomide if you are pregnant. If you become pregnant, contact your health care provider right away. See the Pregnancy section for more details.
Liver Problems. Leflunomide should not be used if your liver is not working as well as it should be. If there is a concern about the health of your liver, your health care provider may do tests to see if it is working well enough to take this medicine.
Drug Interactions. Leflunomide should not be taken while you are using certain other medicines. Before taking leflunomide, tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.
What should I know about leflunomide before taking it?
Do not take leflunomide unless it has been prescribed to you by a health care provider. Take it as prescribed.
Do not share leflunomide with other people, even if they have the same condition as you. It may harm them.
Keep leflunomide out of the reach of children.
Keep all appointments to have your blood checked before and after starting leflunomide.
Talk with your health care provider before stopping leflunomide. They may give you a treatment to help remove the medicine from your body. Without this step, the medicine can stay in your blood for a long time, even up to two years, after your last dose.
If you or your partner can become pregnant, use effective birth control while taking leflunomide. Continue using birth control after stopping leflunomide, until the medicine is out of your body, as confirmed by a blood test. If you and your partner plan to become pregnant, your health care provider if they can give you a treatment to help remove the medicine from your body. Ask your health care provider if you have any questions.
People who are 60 years or older can be at greater risk of some side effects from leflunomide. Talk to your health care provider about your risks if you are in this age group.
What should I tell my health care provider before taking leflunomide?
Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them know if leflunomide is right for you.
In particular, make sure that you discuss any of the following.
Vaccines. Talk with your health care provider about any vaccines that you may need. You should not receive certain vaccines right before, after, or while taking leflunomide. Tell your health care provider about any vaccines you have recently received or have scheduled.
Current and Past Health Conditions. Tell your health care provider if you have any of the following.
- Kidney or liver problems
- Previous or current infections, such as tuberculosis (TB)
- Wounds or sores
- Problems affecting your immune system, such as HIV
- High blood pressure
- Lung problems
- Diabetes
- Upcoming surgery
Pregnancy. Leflunomide can harm an unborn baby. You should not be pregnant when you start leflunomide. If you or your partner can become pregnant, talk to your health care provider about your birth control options. Tell your health care provider right away if you are pregnant, think you are pregnant, or plan to become pregnant. If you become pregnant while or after taking leflunomide, your health care provider may give you a treatment to help remove the medicine from your body. You can sign up for the pregnancy registry by calling 877-311-8972. This registry collects safety information about the use of leflunomide during pregnancy.
Breastfeeding. Do not take leflunomide while you are breastfeeding. It is not known if leflunomide passes into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed.
Interactions
Does leflunomide interact with foods or drinks?
There are no known interactions between leflunomide and foods or drinks.
It is unknown if drinking alcohol will affect leflunomide, but heavy drinking can slow your immune response and make it harder for your body to fight infections. Infections, including some serious infections, are a possible side effect of leflunomide. See the Side Effects section for more details. The risk of liver problems may also be increased if you drink alcohol while taking leflunomide.
Does leflunomide interact with other medicines (drug interactions)?
Always tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.
In particular, make sure that you discuss if you are using any of the following before taking leflunomide.
- Teriflunomide (Aubagio), which is a medicine used for multiple sclerosis
- A statin, such as atorvastatin (Lipitor and others) or rosuvastatin (Crestor), which is a medicine to lower cholesterol
- A birth control pill, patch, vaginal ring, implant, injection, or intrauterine device (IUD) that contains hormones
- Warfarin, which is a blood thinner
- Repaglinide, which is a medicine commonly used to help lower blood sugar levels in people with type 2 diabetes
- Rifampin (Rifadin), which is a medicine commonly used to treat an infection called tuberculosis
Some other medicines may alter the blood levels of leflunomide, and vice versa. Tell your health care provider about all medicines that you take or have recently taken.
This may not be a complete list of medicines that can interact with leflunomide. Always check with your health care provider.
Overdose/Missed Dose
What should I do if I accidentally use too much leflunomide?
If you or someone else has taken too much leflunomide, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.
What should I do if I miss a dose of leflunomide?
If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and only take the next dose. Do not take double or extra doses.