Leflunomide (Arava) is a non-biologic, disease-modifying antirheumatic drug (DMARD). It's used to treat rheumatoid arthritis (RA) in adults. This medication is a tablet that's taken by mouth once per day. Your care team will regularly follow up with you throughout treatment because leflunomide (Arava) can potentially cause many side effects. Common side effects include stomach upset, headache, rash, hair loss, and high blood pressure. Liver damage and severe infections are some of the rarer, but more serious, side effects.
Leflunomide (Arava) is a non-biologic, disease-modifying antirheumatic drug (DMARD). It blocks certain proteins and cells of the immune system that are overactive from turning on. This lowers inflammation in the joints, which helps treat symptoms and prevent joint damage in people with rheumatoid arthritis.
Source:Â DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
Bloody or cloudy urine
difficult or painful breathing
difficult, burning, or painful urination
dizziness
frequent urge to urinate
headache
loss of appetite
nausea or vomiting
tightness in the chest
yellow eyes or skin
Less common
Burning feeling in the chest or stomach
burning, prickling, or tingling sensation in the fingers or toes
fast or pounding heartbeat
indigestion
joint or muscle pain or stiffness
severe stomach pain
tenderness in the stomach area
unusual tiredness or weakness
Incidence not known
Area rash
black or tarry stools
bleeding gums
blistering, peeling, or loosening of the skin
blood in the stools
burning, numbness, tingling, or painful sensations
chills
clay-colored stools
confusion
continuing vomiting
cough or hoarseness
dark urine
fainting
fever with or without chills
general feeling of tiredness or weakness
high fever
large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
light-colored stools
lightheadedness
lower back or side pain
pains in the stomach, side, or abdomen, possibly radiating to the back
pale skin
pinpoint red spots on the skin
rapid, shallow breathing
red skin lesions, often with a purple center
red, irritated eyes
sores, ulcers, or white spots in the mouth or on the lips
swollen glands
unexplained bleeding or bruising
unpleasant breath odor
unsteadiness or awkwardness
unusual bleeding or bruising
upper right abdominal or stomach pain
vomiting of blood
weakness in the arms, hands, legs, or feet
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Can cause a lot of side effects (e.g., stomach upset, infections, hair loss, liver problems, skin reactions)
Can stay in your body for a few years after you stop treatment
Can't use during pregnancy or in children
Mark your appointments on your calendar to see your rheumatologist and to get any lab tests done (e.g., liver tests, blood cell count, blood pressure checks). These follow-ups are important because your rheumatologist is making sure that the medication is working well for you and is checking for any side effects.
Take leflunomide (Arava) at the same time every day with or without food. Keep in mind that nausea and diarrhea are possible side effects, so taking it with food can help prevent or ease stomach upset.
Before you get any vaccines, let your primary care provider or pharmacist know that you're taking leflunomide (Arava). They can make sure the vaccine is safe for you. In general, avoid getting live vaccines during treatment. This medication weakens your immune system. This might make live vaccines work less well for you and make you get sick from the vaccine itself. After you stop leflunomide (Arava), don't get a live vaccine until your care team says you can.
Let your rheumatologist know if you want to stop taking leflunomide (Arava). This medication can stay in your body for up to 2 years after you've stopped taking it. When you want to stop the medication, you'll need to go through a specific process to "quickly" get rid of leflunomide from your body. This process involves taking either cholestyramine or activated charcoal for 11 days. Ask your rheumatologist for more information about stopping the medication.
Tell your rheumatology care team about all the medications you're taking or planning to take.Leflunomide (Arava) can interact with other medications. For example, it can cause the blood thinner warfarin (Coumadin) to work less well and raise your risk for blood clots. Additionally, taking leflunomide (Arava) with medications that weaken your immune system could raise your risk for serious infections.
If you or your partner is able to become pregnant, you must use birth control while you're taking leflunomide (Arava). This medication has a risk of causing severe harm to an unborn baby. Tell your rheumatologist right away if you're pregnant or thinking of getting pregnant while you're taking leflunomide (Arava).
It's not recommended to breastfeed while you're taking leflunomide (Arava) because the medication can potentially cause severe side effects in your baby. Talk to your rheumatologist about your options.
Leflunomide (Arava) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
You can't take leflunomide (Arava) if you're pregnant because the medication can cause severe and life-threatening harm to an unborn baby. Your rheumatologist might ask you to do a pregnancy test before you start leflunomide (Arava) to make sure you're not pregnant.
If you can become pregnant, you must use effective birth control while you're taking leflunomide (Arava). Let your rheumatology care team know right away if you become pregnant at any time during and even after treatment. You'll need to take specific medications to help your body get rid of leflunomide (Arava) quickly to lower the risk of harm to the baby. It's also encouraged to report the pregnancy to the manufacturer by calling 1-877-311-8972.
Risk factors: History of liver problems | Taking medications that can harm the liver
Some people had liver damage while they were taking leflunomide (Arava). Some cases of liver damage were severe and required a liver transplant.
Tell your care team about your medical history and all the medications you take or plan to take. The risk for liver damage during treatment is higher for people who already have liver problems or for people who take other medications that harm the liver. You won't be able to take leflunomide (Arava) if you have serious liver problems.
Your provider will monitor your liver closely through blood tests while you're taking leflunomide (Arava). They might ask you to stop leflunomide (Arava) if you have symptoms of liver damage, such as feeling more tired, having little to no appetite, having yellowing of the skin or eyes, or dark-colored urine.
Risk factors: Active, chronic, or recurrent infection | Having other medical conditions that raise your risk of infection | Living in or traveling to places with high rates of infections | Taking medications that weaken your immune system
Leflunomide (Arava) can affect your body's ability to fight infections. This can raise your risk for serious and sometimes life-threatening bacterial, viral, or fungal infections. Before you start leflunomide (Arava), your rheumatologist will screen you for infections, such as tuberculosis (TB), to make sure the medication is safe for you to take.
To be safe, your rheumatologist will probably recommend a different treatment for your RA if you already have a weakened immune system because of a medical condition (e.g., cancer) or because of other medications (e.g., transplant medications).
Go to the hospital right away if you develop symptoms of an infection, such as fever, cough, difficulty breathing, weakness, sweating, chills, or diarrhea, while you're taking leflunomide (Arava). You should get tested for an infection and get proper treatment if needed. You might have to stop taking leflunomide (Arava) so your body can fight the infection.
Leflunomide (Arava) can lower your blood cell counts. This means your platelet count can drop (thrombocytopenia), putting you at risk for severe bleeding. You might also be at risk for anemia. In addition, having a lower white blood cell count can raise your risk for infection.
Your rheumatologist will order blood draws to check your blood cell counts regularly throughout treatment. Tell your care team if you have symptoms of low platelets, like unusual bleeding, bleeding that lasts for a long time, difficulty stopping bleeds, or easy bruising. Also get medical help if you think you have an infection — look out for fever, chills, tiredness, cough, body aches, and runny nose.
Severe allergic reactions to leflunomide (Arava) are possible, including life-threatening reactions like facial swelling and anaphylaxis (e.g., closing of the throat). Though rare, this medication can also cause drug reaction with eosinophilia and systemic symptoms (DRESS), which can look like fever, rash, and swollen lymph nodes.
Leflunomide (Arava) can also cause sudden and serious skin reactions like Stevens-Johnson Syndrome (SJS). Symptoms can include fever, body aches, rash, peeling skin, painful blisters all over your body, and swelling of the face.
Stop using leflunomide (Arava) and get medical attention right away if you have any allergic reactions or skin reactions to the medication.
Risk factors: Age 60 years and older | Taking other medications that can worsen nerve pain | Diabetes
Leflunomide (Arava) can cause nerve pain. For most people, it goes away after stopping the medication. But a few people might continue to experience nerve pain even after they stop leflunomide (Arava). If you start having nerve pain during treatment, your rheumatologist might ask you to stop leflunomide (Arava). You might have to go through a process that helps get rid of the medication from your body quickly to ease this side effect. Contact your care team if you have any pain, numbness, or tingling in your hands or feet.
Risk factors: History of lung or breathing problems
Though rare, people who took leflunomide (Arava) have developed interstitial lung disease (ILD), or scarring of the lung tissue. This lung problem can occur at any time during treatment and it can sometimes be life-threatening. Call your rheumatologist right away if you have symptoms of ILD, like cough or trouble breathing. You might need to go through a special process of taking certain medications to get rid of leflunomide (Arava) from the body quickly to help prevent further lung damage.
Leflunomide (Arava) might raise your blood pressure. Your rheumatologist will check your blood pressure before you start treatment. The care team will also check your blood pressure at every follow-up visit while you're taking leflunomide (Arava). Let your care team know if you notice that your blood pressure is higher than what it was before you started leflunomide (Arava).
After you stop taking leflunomide (Arava), it can take up to two years for your body to completely get rid of the medication. This is important to consider if you're planning on becoming pregnant or have unwanted or serious side effects. Your rheumatologist might prescribe cholestyramine (Prevalite) or activated charcoal for you to take for 11 days to help speed up the process of removing leflunomide (Arava) from your body.
Loading dose: The typical dose is 100 mg by mouth once per day for 3 days.
Maintenance dose The typical dose is 20 mg by mouth once per day.
Your rheumatologist might not prescribe the loading dose for you at the beginning of treatment if you're at high risk for serious side effects from the medication (e.g., liver problems, low blood cell count). In this case, you'll start off and continue with the maintenance dose.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Severe liver problems
Currently pregnant
Not using birth control (for women who are able to become pregnant)
Allergy to leflunomide (Arava) or Aubagio (teriflunomide)
Taking Aubagio (teriflunomide) (a medication for multiple sclerosis)
Acute lymphoblastic leukemia (ALL); given with other chemotherapy
Treatment and prevention of meningeal leukemia
Non-Hodgkin lymphoma (NHL)
Osteosarcoma; given with other chemotherapy
Breast cancer; given with other chemotherapy
Gestational trophoblastic neoplasia (GTN); given with other chemotherapy
Ulcerative colitis (UC) - immediate-release and delayed release tablets
Rheumatoid arthritis (RA) - delayed-release tablets only
Polyarticular juvenile rheumatoid arthritis - delayed-release tablets only
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American College of Rheumatology. (n.d.). Rheumatologist.
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National Heart, Lung, and Blood Institute. (2022). Thrombocytopenia.
Osiri, M., et al. (2003). Leflunomide for the treatment of rheumatoid arthritis. Cochrane Database of Systematic Reviews.
Padda, I. S., et al. (2023). Leflunomide. StatPearls.
Strand, V., et al. (1999). Treatment of active rheumatoid arthritis with leflunomide compared with placebo and methotrexate. Archives of Internal Medicine.
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