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pronounced as (rit″ le sye′ ti nib)


Taking ritlecitinib may decrease your ability to fight an infection and increase your risk of getting a serious infection, including fungal, bacterial, or viral infections that spread through the body. These infections may need to be treated in a hospital and may cause death. Tell your doctor if you often get any type of infection or if you think you may have any type of infection now. This includes minor infections (such as open cuts or sores), infections that come and go (such as cold sores), and chronic infections that do not go away. Also tell your doctor if you have or have ever had diabetes, human immunodeficiency virus (HIV), acquired immunodeficiency syndrome (AIDS), hepatitis B (a viral infection that affects the liver), hepatitis C virus infection (HCV: an ongoing liver infection), herpes zoster (shingles; a rash that can occur in people who have had chickenpox in the past), a lung disease, or any other condition that affects your immune system. Your doctor may do blood tests to see if you have any of these diseases. Tell your doctor if you are taking medications that decrease the activity of the immune system. Make sure you have discussed any medications you are currently taking or plan to take with your doctor and pharmacist before starting ritlecitinib.

Your doctor will monitor you for signs of infection during and after your treatment. If you have any of the following symptoms before you begin your treatment or if you experience any of the following symptoms during or shortly after your treatment, call your doctor immediately: fever; sweating; chills; muscle aches; cough; shortness of breath; weight loss; warm, red, or painful skin; sores on the skin; frequent, painful, or burning feeling during urination; diarrhea; or excessive tiredness.

You may already be infected with tuberculosis (TB; a serious lung infection) but not have any symptoms of the disease. In this case, taking ritlecitinib may make your infection more serious and cause you to develop symptoms. Your doctor will perform a skin test to see if you have an inactive TB infection. If necessary, your doctor will give you medication to treat this infection before you start using ritlecitinib. Tell your doctor if you have or have ever had TB, if you have lived in or visited a country where TB is common, or if you have been around someone who has TB. If you have any of the following symptoms of TB, or if you develop any of these symptoms during your treatment, call your doctor immediately: cough, coughing up bloody mucus, weight loss, loss of muscle tone, or fever.

Taking ritlecitinib may increase the risk that you will develop a lymphoma (cancer that begins in the cells that fight infection) or other types of cancers such as skin cancer or lung cancer. Tell your doctor if you have or have ever had any type of cancer. Plan to avoid unnecessary or prolonged exposure to sunlight and to wear protective clothing and sunscreen. Also tell your doctor if you smoke or if you have ever smoked.

Taking ritlecitinib may cause serious or life-threatening heart problems, such as a heart attack or stroke, or serious or life-threatening blood clots in the lungs or legs. Also tell your doctor if have or have ever had a heart attack or other heart problems; a stroke; a blood clot in your legs, arms, or lungs, or in the arteries; high cholesterol; high blood pressure; or diabetes. If you experience any of the following symptoms during your treatment, call your doctor immediately or get emergency medical treatment: pain in the chest, arms, back, neck, jaw, or stomach; breaking out in cold sweat; feeling light-headed; dizziness; numbness or weakness in face, arm, or legs; slow or difficult speech; sudden shortness of breath or difficulty breathing; swelling of a leg or arm; leg pain; redness, discoloration, or warmth in the legs or arms.

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests before, during, and after your treatment to check your body's response to ritlecitinib.

Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with [Drug X] and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website ( {or the manufacturer's website} to obtain the Medication Guide.

Why is this medication prescribed?

Ritlecitinib is used for treatment of alopecia areata (a disease that causes sudden hair loss) in adults and children 12 years of age and older. Ritlecitinib is in a class of medications called kinase inhibitors. How it work to help stop hair loss in individuals with alopecia areata is not well understood.

How should this medicine be used?

Ritlecitinib comes as a capsule to take by mouth. It is usually taken with or without food once a day. Take ritlecitinib at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take ritlecitinib exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the capsules whole; do not split, chew, or crush them.

Your doctor may need to temporarily or permanently stop treatment if you experience certain severe side effects. Be sure to tell your doctor how you are feeling during your treatment and keep all appointments with the lab.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking ritlecitinib,

  • tell your doctor and pharmacist if you are allergic to ritlecitinib, any other medications, or any of the ingredients in ritlecitinib capsules. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
  • some medications should not be taken with ritlecitinib. Other medications may cause dosing changes or extra monitoring when taken with ritlecitinib. Make sure you have discussed any medications you are currently taking or plan to take before starting ritlecitinib with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking ritlecitinib, please get the advice of your doctor or pharmacist.
  • tell your doctor if you have or have ever had liver disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking ritlecitinib, call your doctor.
  • do not have any vaccinations without talking to your doctor. Your doctor may recommend you receive some vaccines before starting ritlecitinib.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is less than 8 hours before the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Ritlecitinib may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • headache
  • diarrhea
  • acne
  • itchiness
  • fever
  • dizziness

Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately {or get emergency medical treatment}:

  • hives, rash, trouble breathing, swelling of lips, tongue or throat

Ritlecitinib may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to ritlecitinib.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Litfulo®
Last Revised - 08/01/2015