Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Olumiant (Baricitinib). If you are concerned about side effects, discuss the risks and benefits of Olumiant (Baricitinib) with your doctor.

The following side effects have been reported by at least 1% of people taking Olumiant (Baricitinib). Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• Acne
• back pain
• Cold Sores
• cold symptoms (e.g., runny nose, sinus congestion)
• Constipation
• cough
• Diarrhea
• dizziness
• fatigue
• Headaches
• heartburn
• joint pain
• mouth and throat pain
• muscle spasms
• nausea
• rash
• sinus infection
• stomach pain
• trouble sleeping
• vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• increased blood pressure
• signs of Anemia (low red blood cells; e.g., dizziness,  pale skin, unusual tiredness or weakness, shortness of breath)
• signs of infection (symptoms may include Fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
• skin infection (e.g., red, swollen or painful skin)
• new skin lesions or change in appearance of existing skin lesions
• symptoms of Bronchitis (e.g., cough, tiredness, shortness of breath)
• symptoms of pneumonia (e.g., coughing, fever, fatigue)
• symptoms of Shingles (e.g., skin rash or blisters with itching, burning or tingling pain, usually on one side of the body)
• symptoms of stomach or bowel infection (e.g., vomiting, stomach pain, watery or bloody diarrhea, loss of appetite)
• symptoms of a urinary tract infection (e.g. pain when urinating, urinating more often than usual, low back or flank pain)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of a blood clot in the arm or leg (tenderness, pain, swelling, warmth, or redness in the arm or leg) or lungs (difficulty breathing, sharp chest pain that is worst when breathing in, coughing, coughing up blood, sweating, or passing out)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Olumiant (Baricitinib).

Each light pink, film-coated, oblong tablet with a recessed area on each face of the tablet surface, debossed with "Lilly" on one side and "2" on the other, contains 2 mg of Olumiant (Baricitinib). Nonmedicinal ingredients: croscarmellose sodium, magnesium stearate, mannitol, and microcrystalline cellulose; colour coating ferric oxide, lecithin (soya), polyethylene glycol, polyvinyl alcohol, talc and titanium dioxide.

Do not take Olumiant (Baricitinib) if you are allergic to Olumiant (Baricitinib) or any ingredients of the medication.

There may be an interaction between Olumiant (Baricitinib) and any of the following:

• Abatacept
• Adalimumab
• Anakinra
• Azathioprine
• BCG
• Belimumab
• cancer medications (e.g., Carboplatin, Cyclophosphamide, Doxorubicin, Ifosfamide, Vincristine)
• Clozapine
• corticosteroids (e.g., budesonide, Dexamethasone, Hydrocortisone, fluticasone, Prednisone)
• Cyclosporine
• Deferiprone
• Denosumab
• echinacea
• eculizumab
• Etanercept
• Fingolimod
• Glatiramer
• Golimumab
• Hydroxyurea
• Imiquimod
• Infliximab
• Leflunomide
• mycophenolate
• Natalizumab
• Nivolumab
• Pimecrolimus
• Roflumilast
• Sarilumab
• Tacrolimus
• Tocilizumab
• Tofacitinib
• Tolvaptan
• Trastuzumab

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Olumiant (Baricitinib). Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use Olumiant (Baricitinib).

Blood cholesterol: Olumiant (Baricitinib) has been associated with increased blood cholesterol levels. If you have elevated blood cholesterol levels, discuss with your doctor how Olumiant (Baricitinib) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Olumiant (Baricitinib), and whether any special monitoring is needed.

Blood Clots: Olumiant (Baricitinib) may increase the chance of blood clot formation, causing reduction of blood flow to organs or the extremities.

If you have a history of clotting you may be at increased risk of experiencing blood clot-related problems such as Heart Attack, Stroke, or clots in the lungs or deep veins of your leg. Discuss with your doctor how Olumiant (Baricitinib) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Olumiant (Baricitinib), and whether any special monitoring is needed.

If you experience symptoms such as sharp pain and swelling in the leg, difficulty breathing, chest pain, blurred vision or difficulty speaking, contact your doctor immediately.

Cancer: Rarely, people taking Olumiant (Baricitinib) and similar medications have developed cancer, including lymphoma and non-melanoma Skin Cancer. In general, people with rheumatoid arthritis who take medications that suppress the immune system over long periods of time may also have a higher risk of developing lymphoma, even if they don't take Olumiant (Baricitinib). Discuss any concerns you have with your doctor.

Gastrointestinal perforation: People who take anti-inflammatory medications such as NSAIDs or corticosteroids while they are also taking Olumiant (Baricitinib) may be more at risk of experiencing a tear in the lining of the stomach, which can cause serious bleeding. This can occur without abdominal pain.

If you notice bloody or black and tarry stools, or vomit blood or material that looks like coffee grounds, seek medical help immediately.

Infection: Olumiant (Baricitinib) reduces your body's response to infection. People taking Olumiant (Baricitinib) are at an increased risk of developing serious infections that can be difficult to treat and may cause hospitalization or death. These infections include Tuberculosis and fungal infections as well as infections caused by bacteria and viruses. These infections are more likely to occur if you are taking another medication that reduces the activity of the immune system.

If you have been exposed to tuberculosis, have a history of serious or recurrent infections or have medical conditions that may increase the likelihood of developing infections, discuss with your doctor how Olumiant (Baricitinib) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Olumiant (Baricitinib), and whether any special monitoring is needed.

If possible, avoid contact with people with contagious infections. Tell your doctor immediately if you notice signs of an infection, such as fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness.

Kidney function: Decreased kidney function may cause Olumiant (Baricitinib) to build up in the body, causing side effects. If you have reduced kidney function or Kidney Disease, discuss with your doctor how Olumiant (Baricitinib) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Olumiant (Baricitinib), and whether any special monitoring is needed.

Liver function:  People taking Olumiant (Baricitinib) may have changes in liver function that produce abnormal liver test results. Your doctor will recommend regular liver tests while you are taking Olumiant (Baricitinib).

If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.

People with severely reduced liver function should not use Olumiant (Baricitinib).

Lung inflammation: Lung inflammation (interstitial lung disease), causing difficulty breathing has occurred in some people taking Olumiant (Baricitinib). This complication can be serious and sometimes fatal.

If you experience new or worsening shortness of breath or cough (with or without fever) at any time while you are taking Olumiant (Baricitinib) contact your doctor immediately.

Vaccinations: People taking Olumiant (Baricitinib) should not receive certain vaccines. Talk to your doctor about whether any vaccines you are scheduled to take may be used with Olumiant (Baricitinib).

Pregnancy: Olumiant (Baricitinib) should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking Olumiant (Baricitinib), contact your doctor immediately. Women who are of childbearing age should use appropriate birth control while taking Olumiant (Baricitinib) and for at least 1 week after taking the last dose of medication.

Breast-feeding: It is not known if Olumiant (Baricitinib) passes into breast milk. If you are a breast-feeding mother and are taking Olumiant (Baricitinib), it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using Olumiant (Baricitinib) have not been established for children.

Seniors: People over the age of 65 years may be more at risk of side effects from Olumiant (Baricitinib).