Why is this medication prescribed?

Avatrombopag is used to treat thrombocytopenia (a low number of platelets [type of blood cell needed for blood clotting]) in people with chronic (ongoing) liver disease who are scheduled to have a medical or dental procedure to help prevent bleeding complications. It is also used to treat thrombocytopenia in people with chronic immune thrombocytopenia (ITP; an ongoing condition that may cause unusual bruising or bleeding due to an abnormally low number of platelets in the blood) who were not helped with another treatment. Avatrombopag is in a class of medications called thrombopoietin (TPO) receptor agonists. It works by causing the body to produce more platelets.

How should this medicine be used?

Avatrombopag comes as a tablet to take by mouth. For the treatment of thrombocytopenia in people with chronic liver disease who are scheduled to have a procedure, it is usually taken with food once a day for 5 days, starting 10 to 13 days before the procedure. For the treatment of thrombocytopenia in people with ITP, it is usually taken once daily with food for as long as directed. Take avatrombopag 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 avatrombopag exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

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 avatrombopag, tell your doctor and pharmacist if you are allergic to avatrombopag, any other medications, or any of the ingredients in avatrombopag tablets. Ask your pharmacist for a list of the ingredients. tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: amiodarone (Nexterone, Pacerone); aprepitant (Emend); certain antifungals such as fluconazole, itraconazole (Onmel, Sporanox), ketoconazole, or voriconazole (Vfend); carbamazepine (Carbatrol, Epitol, Equetro, Tegretol, Teril); clarithromycin (Biaxin, in Prevpac); diltiazem (Cardizem, Cartia, Diltzac, Taztia); enzalutamide (Xtandi); erythromycin (E.E.S., Erythrocin, others; certain medication to treat HIV such as efavirenz (Sustiva, in Atripla), indinavir (Crixivan), nelfinavir (Viracept), or nevirapine (Viramune); phenobarbital; phenytoin (Dilantin, Phenytek); rifabutin (Mycobutin); rifampin (Rifadin, Rimactane, in Rifamate, in Rifater); ritonavir (Norvir, in Kaletra, others), or saquinavir (Invirase); nefazodone; and verapamil (Calan, Covera, Verelan). Many other medications may also interact with avatrombopag, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.

tell your doctor what herbal products you are taking, especially St. John's wort.

tell your doctor if you have or have ever had a blood clot, or a genetic condition that could lead to blood clots.

tell your doctor if you are pregnant, or plan to become pregnant. If you become pregnant while taking avatrombopag, call your doctor.

tell your doctor if you are breastfeeding. Your doctor will probably tell you not to breastfeed during your treatment and for 2 weeks after your final dose.

What special dietary instructions should I follow?

Do not eat grapefruit or drink grapefruit juice while using this medication.

What should I do if I forget a dose?

If you are taking avatrombopag to treat thrombocytopenia just before a procedure, take the missed dose as soon as you remember it. If it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule, but be sure to finish taking all of the medication (even if they are not taken 5 days in a row). Do not take a double dose to make up for a missed one.

If you are taking avatrombopag to treat chronic immune thrombocytopenia, take the missed dose as soon as you remember it. If it is almost time for 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?

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

extreme tiredness

headache

nosebleeds or gum bleeding

joint pain

Some side effects can be serious. If you experience any of these symptoms call your doctor immediately:

swollen, painful, red, or tender leg

shortness of breath, fever, cough, chest pain, or fast heartbeat

stomach pain or tenderness

swelling of hands or feet

Avatrombopag 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 (https://www.fda.gov/Safety/MedWatch) 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. https://www.upandaway.org

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 (https://goo.gl/c4Rm4p) 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 https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

swollen, painful, red or tender leg

shortness of breath, cough, chest pain, fast heartbeat

stomach pain or tenderness

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests before you start treatment to decide your dose of avatrombopag and on the day of the procedure.

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.