Side Effects of Arava (Leflunomide)


Arava (leflunomide) is among the many medications taken to manage the pain, inflammation, stiffness, and other symptoms of rheumatoid arthritis (RA). A disease-modifying antirheumatic drug (DMARD) that’s been available since 1998, it comes in tablet form.

It is usually taken once daily, though larger doses—called loading doses—may be prescribed for the first two to three days. A loading dose is sometimes given for medications that take a long time to build up in the body.

RA is a type of arthritis in which the body’s immune system attacks and damages the joints. Arava directly reduces the inflammation caused by this disease, which eases pain to help restore mobility and function.

In some cases, it also reverses the progression of this disease. While Arava can help make RA more tolerable and manageable, it will not outright cure this condition. It may take several weeks for you to experience an improvement in joint pain and swelling. The complete benefits of Arava may not be seen until six to 12 weeks after starting the medication.

As with all pharmaceutical drugs, there are some risks associated with its use. Like other drugs of its class, Arava causes a host of more common side effects, such as diarrhea, vomiting, heartburn, and headache, among others. More critically, the use of this drug can also lead to more severe side effects, including mouth sores, breathing difficulties, and others.

If you have RA and are taking or considering taking Arava, it’s important to understand what these are and what to do about them. Safe use of any medication also means knowing when it’s time to call a healthcare provider.

Common Side Effects

When it comes to common side effects, it’s OK if you experience them; however, you should let your healthcare provider know if they persist or become problematic. Most commonly—about 17% of the time—Arava can cause diarrhea. Frequently, this symptom will improve with time. If diarrhea persists, the dose of Arava may need to be reduced.

What side effects are most often seen with Arava use? Here’s a quick breakdown:

  • Headache
  • Nausea/vomiting
  • Heartburn
  • Dizziness
  • Sudden weight loss
  • Back pain
  • Muscle weakness or pain
  • Burning, numbness, pain, or tingling in hands and feet
  • Hair loss
  • Dry skin
  • Leg cramping

Throughout the course of your treatment, be vigilant about how you’re feeling and never hesitate to seek help if anything seems off or awry. The better you’re able to communicate with your healthcare provider, the more effective your treatment will be.

Serious Side Effects

Though much rarer, serious side effects can occur with Arava. This drug has been in use for decades and is largely considered safe. However, prolonged use can impair liver function and have other effects on the body.

If you experience any of the following rarer and more severe side effects, you should let your healthcare provider know:

  • Rash alongside fever or on its own
  • Mouth sores
  • Difficulty breathing
  • Itching
  • Development or worsening of cough
  • Chest pains
  • Pale skin

When to Call Your Healthcare Provider

In rare instances, patients experience severe adverse reactions to Arava, which prompt immediate medical attention. Consider these medical emergencies and act accordingly if you develop:

  • Signs of impaired liver function: These include jaundice (yellowing of the skin and eyes) and abdominal pain. Throughout the course of treatment, your liver function will be monitored.
  • Symptoms of pancytopenia: This is a condition characterized by low levels of red and white blood cells (anemia and leukopenia, respectively) and platelets (thrombocytopenia). Symptoms include fatigue, infection, and easy bruising.
  • Severe peeling of the skin alongside flu-like symptoms: These are signs of toxic epidermal necrolysis (also known as Stevens-Johnson syndrome), a type of severe allergic reaction.
  • Development of unusual growths (can be a sign of cancer or infection): These arise since Arava use can potentially suppress immune function.
  • Severe allergic reaction: These include swelling of the face, lips, throat, or tongue, and breathing problems.
  • Signs of infection: These include fever, chills, weakness, mouth sores, sore throat, difficulty swallowing, and red or swollen gums.

Throughout the course of your treatment, be mindful of how you’re feeling, and never hesitate to seek out help, especially if you suspect an adverse reaction.


It often takes extra effort to take Arava safely, and this drug can be dangerous for those with certain conditions. Notably, it’s considered unsafe for certain populations, including:

  • Those who are pregnant: Notably, this drug may cause fetal harm in pregnancy, so if you’re expecting or become pregnant during the course of treatment, let your healthcare provider know. If you’re a female of reproductive age, your practitioner will advise you to use birth control.
  • Those who are breastfeeding: People who breastfeed will also need to stop while taking Arava to ensure the baby’s safety.  
  • Children and infants: It is unknown whether Arava is safe to take for those under 17, so healthcare providers will typically advise against prescribing it to this population.

Those with longstanding liver problems, such as liver failure or hepatitis, should be carefully monitored if taking Arava. If levels of liver enzyme start to dip, you’ll need to be taken off of this drug.

Arava is not recommended for patients with weakened immune systems due to chronic conditions like human immunodeficiency virus (HIV/AIDs), problems with bone marrow, or severe infection. As noted, this drug has a potential immunosuppressive effect that can make these cases worse.

Use of this drug can also increase the risk of infection in general and may cause dormant cases of tuberculosis to become active. Before taking the drug, you’ll need to be tested for the condition, and it would need to be treated.

Notably, too, Arava may interact poorly with alcohol; talk to your healthcare provider about the safety of consuming these beverages while taking this drug.


As with most pharmaceutical drugs, Arava may also interact with other medications, herbs, and supplements you’re taking. In doing so, its efficacy can be compromised, it can stop another substance from working, or drug effects can increase. In these cases, your healthcare provider may need to adjust your dosage or recommend an alternative.

Several drugs may interact with Arava:

Dosages may need to be adjusted in these cases, or another approach will need to be considered altogether.

In addition, herbs, vitamins, and supplements may also interact with Arava, so make sure you have a complete list of what you’re taking with you when you see your healthcare provider. Throughout the course of your treatment, make sure to get your practitioner’s approval before starting any new regimen.  

A Word From Get Meds Info

While the side effects of Arava can be troublesome, know that you have options. If you’re struggling with negative effects, be sure to let your healthcare provider know, as other medications may work better for your case. What’s most important is that you don’t remain silent; the better you’re able to communicate with your medical team, the better off you’ll be.

Treatment of rheumatoid arthritis varies a great deal, especially since there is no outright cure for it. The degree to which rheumatoid arthritis affects your daily activities depends on how you cope with the disease.

You’ll learn what strategies work best for you in managing this disease by staying engaged in your care and establishing good communication with your healthcare professionals.

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