Arava (leflunomide) is a brand-name prescription medication. It’s approved by the Food and Drug Administration (FDA) to treat rheumatoid arthritis (RA) in adults.

Here are some fast facts about Arava:

  • Active ingredient: leflunomide
  • Drug class: disease-modifying antirheumatic drugs (DMARDs)
  • Drug form: oral tablet

Arava is meant to be a long-term treatment for RA.

Like other drugs, Arava tablets can cause side effects. Read on to learn about potential common, mild, and serious side effects. For a general overview of Arava, see this article.

Arava can cause certain side effects, some of which are more common than others. These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

These are just a few of the more common side effects reported by people who took Arava in clinical trials:

* For more information about this side effect, see “Side effect specifics” below.
Arava has a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA). To learn more about this side effect, see “Side effect specifics” below.

Mild side effects can occur with Arava. This list doesn’t include all possible mild side effects of the drug. For more information, you can refer to Arava’s prescribing information.

Mild side effects that have been reported with Arava include:

These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks side effects of the medication. If you develop a side effect while taking Arava and want to tell the FDA about it, visit MedWatch.

* For more information about this side effect, see “Side effect specifics” below.
Arava has a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA). To learn more about this side effect, see “Side effect specifics” below.

Arava may cause serious side effects. The list below may not include all possible serious side effects of the drug. For more information, you can refer to Arava’s prescribing information.

If you develop serious side effects while taking Arava, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Serious side effects that have been reported and their symptoms include:

* Arava has a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA).
† For more information about this side effect, see “Side effect specifics” below.
‡ To learn more about this side effect, see “Pregnancy and breastfeeding while taking Arava” in the “Precautions for Arava” section below.

Arava may cause several side effects. Here are some frequently asked questions about the drug’s side effects and their answers.

Does Arava cause weight loss?

No, Arava isn’t likely to cause weight loss. This side effect wasn’t reported in clinical trials of the drug.

However, Arava may cause loss of appetite, which was a rare side effect in trials of the drug. And loss of appetite can lead to weight loss.

Keep in mind that weight loss can be a sign of liver damage,* which is a possible serious side effect of Arava.

If you have unexplained weight loss while taking Arava, talk with your doctor right away. They can check your liver function or help determine other possible causes of your weight loss.

* Arava has a boxed warning for this side effect. This is the most serious warning from the FDA. To learn more, see the “Side effect specifics” section below.

Do side effects of Arava vary by strength (10 mg, 20 mg, 100 mg)?

It’s not likely. Clinical trials of Arava didn’t show any differences in side effects based on the drug’s strength.

If you’re concerned about your risk of side effects from Arava based on the strength you take, talk with your doctor or pharmacist.

Does Arava cause lung problems?

It’s possible that Arava may cause lung problems. These side effects weren’t reported in clinical trials of the drug. However, certain lung problems have been reported since Arava became available for use.

Specifically, there have been reports of interstitial lung disease (ILD) with Arava. ILD is a group of conditions that can cause scarring or swelling in the lungs. This leads to symptoms such as coughing and shortness of breath. In rare cases, ILD can be fatal.

Tell your doctor right away if you have symptoms of ILD while taking Arava. They may have you stop taking the drug temporarily until they can determine the cause of your symptoms.

You may have a higher risk of ILD if you already have this condition or other lung problems before starting treatment with Arava. Be sure to tell your doctor if you have any lung problems before taking the drug.

Learn more about some of the side effects that Arava may cause.

Hair loss

Hair loss is a possible side effect of Arava. In clinical trials, this was one of the more common side effects.

It’s important to note that rheumatoid arthritis (RA), which Arava is prescribed to treat, can also cause hair loss. If you have hair loss while taking Arava, it could be caused by one or both factors.

What you can do

Below are a few tips for helping reduce hair loss:

  • Gently massage your scalp when washing your hair. Avoid scrubbing your scalp vigorously.
  • Use a conditioner that moisturizes your hair. This should help remove tangles more gently when brushing.
  • Brush or comb your hair only when necessary, such as when styling it.
  • Avoid using styling tools that may be damaging to your hair, such as a curling iron.

If you have hair loss that’s excessive or bothersome while taking Arava, talk with your doctor. They can help determine if your hair loss is due to RA or Arava. They can also suggest other ways to ease your hair loss.

Mouth ulcers

Arava may cause mouth ulcers. This was a common side effect in clinical trials of the drug.

Mouth ulcers are painful sores that can affect your gums, tongue, lips, cheeks, or throat. They may appear as a fluid-filled blister or a small cut. Other symptoms of mouth ulcers include:

  • swelling
  • peeling
  • stinging or burning sensation
  • trouble eating

What you can do

Tell your doctor if you develop bothersome mouth ulcers while taking Arava. They can suggest ways to help ease your symptoms.

High blood pressure

Taking Arava may cause high blood pressure. This was a common side effect in clinical trials of the drug.

High blood pressure doesn’t usually cause any symptoms unless it’s severe. Symptoms of very high blood pressure can include:

What you can do

Your doctor may check your blood pressure before you start taking Arava and periodically during treatment. They may also suggest you check your blood pressure with a home monitor while you take Arava.

Be sure to tell your doctor if you already have high blood pressure before taking the drug. They can advise you on whether it’s safe for you to take Arava while you have this condition.

If you have symptoms of very high blood pressure while taking Arava, tell your doctor right away. They may prescribe blood pressure medication to help manage this side effect.

Liver damage

Taking Arava can cause serious liver damage, such as liver failure. In fact, Arava has a boxed warning about the risk of liver damage. This is a serious warning from the Food and Drug Administration (FDA).

Liver failure wasn’t reported in clinical trials of Arava. However, liver damage has been reported since the drug became available for use. In rare cases, liver damage from Arava can be fatal.

Your risk of liver failure with Arava may be higher if you already have liver problems before you start taking the drug. Your risk is also higher if you take other medications that can harm your liver. This includes the rheumatoid arthritis drug methotrexate (Trexall).

It’s important to watch for the following symptoms of liver problems while taking Arava:

What you can do

Your doctor will order liver function tests for you before you start taking Arava. And they’ll continue to check your liver function while you take the drug. If you develop liver damage while taking Arava, your doctor may switch you to a different treatment.

It may not be safe to take Arava if you already have liver problems. Be sure to tell your doctor about any liver problems you have before starting Arava treatment.

Tell your doctor or pharmacist about all other medications you take. They can advise you if any of your medications may cause liver damage. If you take other drugs that cause liver damage, your doctor may watch your liver function more closely during treatment. Or they may prescribe a medication other than Arava to treat your condition.

Allergic reaction

As with most drugs, Arava can cause an allergic reaction in some people. This side effect occurred in clinical trials, however, it wasn’t common.

Symptoms can be mild or serious and can include:

  • skin rash
  • itching
  • flushing
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What you can do

For mild symptoms of an allergic reaction, call your doctor right away. They may recommend ways to ease your symptoms and determine whether you should keep taking Arava. However, if your symptoms are serious and you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Below are important factors to keep in mind when taking Arava.

Boxed warnings

This drug has boxed warnings about risks of liver damage and harm to a fetus. These are serious warnings from the Food and Drug Administration (FDA).

For details about the risk of liver damage, see the “Side effect specifics” section above. To learn more about the risk of harm to a fetus, see “Pregnancy and breastfeeding while taking Arava” in the “Precautions for Arava” section below.

Other precautions

Be sure to talk with your doctor about your health history before you take Arava. This drug may not be the right treatment option for you if you have certain medical conditions or other factors that affect your health. The conditions and factors to consider include:

Lung problems. Be sure to tell your doctor if you have lung problems before starting treatment with Arava. The drug can cause new or worsening lung problems, such as interstitial lung disease (scarring or swelling in the lungs). Your doctor may recommend a drug other than Arava for you.

Weak immune system. Your doctor may not prescribe Arava for you if you have a weak immune system. This could increase your risk of serious infections, including tuberculosis. Be sure to tell your doctor if you have a weak immune system. They may prescribe a treatment other than Arava for you.

Infection. Before you start taking Arava, tell your doctor if you have any active infections. They’ll likely treat your infection before you start treatment with Arava.

High blood pressure. Arava may cause high blood pressure. If you already have this condition, the drug may increase your blood pressure even more. Your doctor can advise you on whether it’s safe for you to take Arava while you have high blood pressure.

Allergic reaction. If you’ve had an allergic reaction to Arava or any of its ingredients, your doctor will likely not prescribe Arava. Ask your doctor what other medications may be better options for you.

Alcohol with Arava

It should be safe to drink a moderate amount of alcohol on occasion while taking Arava.

Keep in mind that drinking large amounts of alcohol can cause liver disease. Liver damage* is a possible serious side effect of Arava. So drinking large amounts of alcohol while taking Arava could increase your risk of liver problems.

For some people, alcohol may worsen symptoms of rheumatoid arthritis (RA). Arava is prescribed to treat RA. So if you know alcohol worsens your RA symptoms, you’ll likely want to avoid alcohol while taking Arava.

If you drink alcohol, your doctor can advise on the amount that’s safe for you to drink while taking Arava.

* Arava has a boxed warning for this side effect. This is the most serious warning from the FDA. To learn more, see the “Side effect specifics” section below.

Pregnancy and breastfeeding while taking Arava

Below are details about taking Arava while pregnant or breastfeeding.

Pregnancy while taking Arava

If you’re pregnant or planning to become pregnant, you should not take Arava. In fact, the drug has a boxed warning about a risk of harm to a fetus if taken during pregnancy. This is a serious warning from the FDA.

Arava may cause harm to a fetus. Because of this risk, your doctor will make sure you have a negative pregnancy test before starting treatment with Arava. If you become pregnant while taking Arava, it’s important to tell your doctor right away.

If you’re able to become pregnant, it’s recommended that you use an effective form of birth control while taking Arava. You may need to keep using birth control for up to 2 years after you stop taking the drug.

Talk with your doctor if you plan to become pregnant within 2 years after stopping Arava treatment. Your doctor may give you treatments that help your body get rid of the drug faster. And this could lower the risk of harm to a fetus if you become pregnant during this time.

Arava pregnancy registry

If you become pregnant while taking Arava, consider enrolling in a pregnancy registry.

A pregnancy registry helps gather details about how certain medications can affect pregnancy. To learn more, visit this registry website, call 877-311-8972, or talk with your doctor.

Breastfeeding while taking Arava

It’s not known if Arava passes into breast milk during breastfeeding. However, because of the possible risks to a child who is breastfed, it’s advised that you avoid breastfeeding while taking Arava.

If you’re breastfeeding or planning to breastfeed while taking Arava, talk with your doctor. They can recommend other ways to feed your child.

Mild and serious side effects are possible while taking Arava. Most side effects should go away with time. However, if you have bothersome side effects that won’t go away, talk with your doctor or pharmacist.

If you’d like to learn more about Arava, talk with your doctor or pharmacist. They can help answer any questions you have about side effects of taking the drug.

Besides talking with your doctor, you can do some research on your own. These articles might help:

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.