Olumiant (baricitinib) is a brand-name prescription medication. The Food and Drug Administration (FDA) has approved it for the following uses in adults:

Olumiant may be prescribed as a long-term treatment for RA and alopecia areata. For COVID-19 treatment, Olumiant is given for 14 days or until you’re discharged from the hospital, whichever comes first.

Here are some fast facts about Olumiant:

As with other drugs, Olumiant can cause side effects. Read on to learn about its potential common, mild, and serious side effects. For a general overview of Olumiant, including details about who can take it, see this article.

Olumiant can cause certain side effects (also called adverse effects). Some 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 Olumiant in clinical trials:

* For more information about this side effect, see “Side effect specifics” below.

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

Mild side effects that have been reported with Olumiant 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 Olumiant and want to tell the FDA about it, visit MedWatch.

For more information about this side effect, see “Side effect specifics” below.

Olumiant 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 Olumiant’s prescribing information.

If you develop serious side effects while taking Olumiant, 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:

* Olumiant has a boxed warning for this side effect. This is a serious warning from the Food and Drug Administration (FDA). To learn more, see the “Side effect specifics” section below.
† An allergic reaction is possible after taking Olumiant. However, this side effect wasn’t reported in clinical trials. For more information about this side effect, see “Side effect specifics” below.

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

Does Olumiant cause hair loss?

No, Olumiant isn’t known to cause hair loss. Hair loss wasn’t reported as a side effect in clinical trials. In fact, Olumiant may help reduce hair loss caused by certain conditions.

Olumiant is approved to treat moderate to severe rheumatoid arthritis (RA), which may cause hair loss. It’s also approved to treat severe alopecia areata, which is a condition that causes unpredictable hair loss that can affect your scalp and the rest of your body.

Hair loss is a known side effect of other RA medications. For example, methotrexate (Otrexup, Rasuvo, Trexall, Xatmep) is known to cause hair loss.

If you’re concerned about hair loss with RA or Olumiant treatment, talk with your doctor. They can discuss your risk of this side effect. And they can suggest ways to manage hair loss if it happens.

* To learn more about the use of Olumiant for RA, see this article.

Is tiredness a side effect of Olumiant?

Tiredness wasn’t reported as a side effect of Olumiant in clinical trials.

However, tiredness can be a symptom of a low red blood cell level, a side effect of Olumiant. (For more details, see the “Serious side effects of Olumiant” section above.) It’s also possible for tiredness to be a symptom of the condition you’re taking Olumiant to treat.

If you have tiredness while taking Olumiant, talk with your doctor. They can check your red blood cell level to see if it’s low.

Is Olumiant prescribed in 4-mg doses? If so, what are the side effects of this dose?

It’s possible for Olumiant to be prescribed in 4-milligram (mg) doses. A dosage of 4 mg per day is typically prescribed for COVID-19 treatment, and can also be prescribed for severe alopecia areata.

However, a 4-mg dose is not approved to treat rheumatoid arthritis (RA).* The recommended dosage of Olumiant for RA is 2 mg once daily.† You can see this article for details about Olumiant’s dosages.

The side effects of a 4-mg dose of Olumiant are expected to be the same as for the 2-mg dose. To learn more, see Olumiant’s prescribing information.

* To learn more about the use of Olumiant for RA, see this article.
† For details about Olumiant’s dosage, view this article.

Learn more about some of the side effects that Olumiant may cause. To find out how often side effects occurred in clinical trials, see the prescribing information for Olumiant.

Upper respiratory infection

Olumiant may cause upper respiratory infection. This was one of the most common side effects in clinical trials of the drug. Examples of upper respiratory infections include sinus infection, tonsil infection, and the common cold.

Symptoms of upper respiratory infections can include:

What you can do

If you have symptoms of an upper respiratory infection from taking Olumiant, talk with your doctor. They can recommend ways to ease your symptoms. For example, they may suggest taking certain over-the-counter (OTC) medications.

Boxed warnings

Olumiant has boxed warnings about the following risks: serious infection, cancer, serious cardiovascular problems, blood clots, and death. Boxed warnings are serious warnings from the Food and Drug Administration (FDA). They alert doctors and patients about drug effects that may be dangerous.

Serious infection

In rare cases, Olumiant may increase the risk of getting serious infections. And these may be fatal. Below are a few of the serious infections that were reported in clinical trials of Olumiant:

It’s important to watch for symptoms of serious infections while taking Olumiant. The exact symptoms can vary depending on the type of infection. However, in general, infections may cause chills, fever, and fatigue.

What you can do

If you have symptoms of infection while taking Olumiant, tell your doctor right away. They may give you tests to determine what type of infection you may have. And if needed, they may have you stop taking Olumiant until the infection is treated.

Before you start taking Olumiant, your doctor will likely test you for TB. They may test you again from time to time during treatment. If you have TB before starting Olumiant treatment, your doctor will treat it before you start taking the drug. However, if you develop TB while taking Olumiant, they may temporarily stop therapy until they’ve treated the infection.

Cancer

Treatment with Olumiant may increase the risk of certain cancers. There were very rare cases of non-melanoma skin cancer reported in clinical trials of Olumiant.

Lung cancer and lymphoma have also been reported in clinical trials of tofacitinib (Xeljanz, Xeljanz XR). This is a medication that’s similar to Olumiant. However, it isn’t known for sure if Olumiant increases the risk of these cancers.

Symptoms of cancer vary depending on the exact type. However, possible symptoms include:

What you can do

Before starting Olumiant treatment, talk with your doctor about any medical conditions you have. Be sure to tell them if you smoke or have smoked in the past. They can use this information to talk with you about your risk of cancer with Olumiant treatment.

Serious cardiovascular problems

Olumiant may cause serious cardiovascular problems for certain people. These problems include:

Specifically, this risk affects adults ages 50 years or older who have risk factors for cardiovascular disease (a condition relating to the heart and blood vessels). Examples of risk factors include smoking and having a family history of heart disease.

This side effect wasn’t reported in clinical trials of Olumiant. However, it’s been reported with tofacitinib (Xeljanz, Xeljanz XR), a medication that works the same way as Olumiant.

What you can do

Before taking Olumiant, tell your doctor about your medical history. Be sure they know if you or a family member had a stroke, heart attack, or other blood vessel or heart problem in the past. They’ll advise on your risk of cardiovascular problems with Olumiant.

Blood clots

Olumiant may increase the risk of blood clots. This side effect was very rare in clinical trials of Olumiant. Blood clots with Olumiant treatment may occur in your arteries, lungs, or legs.

Possible symptoms of a blood clot include:

In rare cases, blood clots with Olumiant treatment can be fatal.

What you can do

If you have symptoms of a blood clot while taking Olumiant, tell your doctor right away. However, if your symptoms seem severe or life threatening, call 911 or your local emergency number.

If you have this side effect, your doctor may switch you to a different treatment for your condition. And they’ll likely prescribe a treatment for the blood clot.

Increased risk of death

Olumiant may increase the risk of death in adults ages 50 years or older who have risk factors for cardiovascular disease. Examples of these factors include smoking and having a family member with heart disease.

This side effect wasn’t reported in clinical trials of Olumiant. However, it’s been reported with tofacitinib (Xeljanz, Xeljanz XR), a medication that works the same way as Olumiant.

What you can do

If you’re concerned about this risk with Olumiant, talk with your doctor. They can recommend if it’s safe for you to take the drug based on your age and health.

Allergic reaction

As with most drugs, Olumiant can cause an allergic reaction in some people. How often this side effect occurred in clinical trials wasn’t reported.

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 Olumiant. However, if your symptoms are serious and you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Olumiant comes with several precautions that may determine if you can safely take the medication. Read on to learn more.

Boxed warnings

This drug has boxed warnings about the following risks: serious infection, cancer, serious cardiovascular problems, blood clots, and death. These are serious warnings from the Food and Drug Administration (FDA). For details, see the “Side effect specifics” section above.

Other precautions

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

Current or past infections, or an increased risk of infection. Before taking Olumiant, tell your doctor if you have an active infection. They’ll likely want to treat the infection before you start taking the drug.

Also, tell your doctor if you’ve had certain infections in the past, including tuberculosis, hepatitis B, and hepatitis C. Taking Olumiant could cause these infections to become active again and cause symptoms. Your doctor will recommend if Olumiant is safe for you to take.

If you have conditions that increase your risk of infection, be sure to tell your doctor. Examples include HIV, diabetes, and a weak immune system. Your doctor can advise if Olumiant is a safe treatment option for you.

Liver problems. Olumiant treatment can increase the level of liver enzymes in your body.* This could be a sign of liver problems. Olumiant may worsen any liver problems you already have. And you may have a higher risk of this side effect if you already have liver problems. Your doctor can advise if Olumiant is safe for you to take.

Kidney problems. Before taking Olumiant, tell your doctor if you have kidney problems. For mild to moderate kidney problems, they may prescribe you a lower dosage of Olumiant. However, doctors typically will not prescribe Olumiant for people with severe kidney problems.

Ulcers or inflammation in your intestines or stomach. Tell your doctor about any ulcers (sores) you’ve had in your intestines or stomach. Also, tell them if you’ve had diverticulitis (inflammation in your intestines). Olumiant may cause gastrointestinal perforation (holes in the lining of the intestines or stomach).* Your doctor may prescribe a different medication for you if you’ve had these conditions.

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

Changes in white blood cell, red blood cell, or cholesterol levels. Tell your doctor if you have low white blood cell or red blood cell levels or high cholesterol.* Olumiant may worsen these conditions. Your doctor may watch these levels more closely during Olumiant treatment.

* To learn more about these side effects, see the “Serious side effects of Olumiant” section above.

Alcohol with Olumiant

There aren’t any known interactions between alcohol and Olumiant.

If you drink alcohol, talk with your doctor about the amount that’s safe to drink while taking Olumiant.

Pregnancy and breastfeeding while taking Olumiant

It isn’t known if Olumiant is safe to take while pregnant. It also isn’t known if Olumiant passes into breast milk. So you should not breastfeed while taking Olumiant.

Before starting Olumiant treatment, tell your doctor if you’re pregnant or breastfeeding or if you’re planning either. They can discuss the risks and benefits of taking Olumiant with you.

Taking Olumiant may lead to mild or serious side effects. If you have side effects that are bothersome or long lasting, talk with your doctor. They can suggest ways to ease your symptoms.

If you’d like to learn more about Olumiant, 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:

  • More information about Olumiant. For details about other aspects of Olumiant, refer to this article.
  • Dosage. To learn about Olumiant’s dosage, see this article.
  • A look at your condition. For more information about rheumatoid arthritis (RA), see our RA hub. These rheumatology articles may also be helpful. And for more information and updates on COVID-19, see our COVID-19 hub.

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.