Teprotumumab-trbw injection is used to treat thyroid eye disease (TED; Graves' eye disease; a disorder in which the immune system causes inflammation and swelling behind the eye). Teprotumumab-trbw is in a class of medications called monoclonal antibodies. It works by blocking the action of a certain protein in the body that causes inflammation in the eye.

Teprotumumab-trbw injection comes as a powder to be mixed with liquid and injected intravenously (into a vein) by a doctor or nurse in a medical office or hospital. It is usually injected slowly over a period of 60 to 90 minutes on day 1 of a 21 day cycle. The cycle may be repeated 7 times.

You may experience a reaction during or shortly after you receive a dose of teprotumumab-trbw injection. You may receive certain medications before your infusion to prevent a reaction if you had a reaction with previous treatment. Tell your doctor immediately if you experience any of these symptoms during or within 90 minutes after you receive treatment: feeling hot, rapid heartbeat, shortness of breath, headache, and muscular pain.

Your doctor may slow down your infusion, stop your treatment with teprotumumab-trbw injection, or treat you with additional medications depending on your response to the medication and any side effects that you experience. Talk to your doctor about how you are feeling during and after your treatment.

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

Before receiving teprotumumab-trbw,

• tell your doctor and pharmacist if you are allergic to teprotumumab-trbw, any other medications, or any of the ingredients in teprotumumab-trbw injection. Ask your pharmacist for a list of the ingredients.
• tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take.
• tell your doctor if you have or have ever had inflammatory bowel disease, impaired fasting glucose (pre-diabetes), or diabetes.
• tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while you are receiving teprotumumab-trbw injection and for at least 6 months after your final dose. Talk to your doctor about birth control methods that will work for you. If you become pregnant while receiving teprotumumab-trbw injection, call your doctor immediately. Teprotumumab-trbw injection may harm the fetus.
• tell your doctor if you are breastfeeding or plan to breastfeed.

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.

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

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

• muscle spasms
• nausea
• hair loss
• fatigue
• hearing changes (loss of hearing, increased sensitivity to sound)
• changes in ability to taste food
• headache
• dry skin
• missed, irregular, or painful menstrual periods
• decreased weight
• change in appearance or color of nails

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

• diarrhea, rectal bleeding, abdominal pain and cramping
• extreme thirst, frequent urination, extreme hunger, blurred vision, weakness

Teprotumumab-trbw may cause other side effects. Call your doctor if you have any unusual problems while receiving 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 (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

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

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to teprotumumab-trbw injection.

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.