Before taking teriflunomide, tell your doctor or pharmacist if you are allergic to it; or to leflunomide; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: bone marrow/blood disorder, immune system disorder (such as due to cancer, HIV infection), current/recent infection (such as tuberculosis), high blood pressure, liver problems, lung disease.

Teriflunomide can make you more likely to get infections or may make current infections worse. Stay away from anyone who has an infection that may easily spread (such as chickenpox, COVID-19, measles, flu). Talk to your doctor if you have been exposed to an infection or for more details.

Tell your health care professional that you are using teriflunomide before having any immunizations/vaccinations. Avoid contact with people who have recently received live vaccines (such as flu vaccine inhaled through the nose).

To lower the chance of getting cut, bruised, or injured, use caution with sharp objects like razors and nail cutters, and avoid activities such as contact sports.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Teriflunomide may pass into the semen of men treated with this medication and the effects on sperm are unknown. Men not wishing to father a child with their female partners should use reliable birth control (such as condoms). After stopping this medication, men wishing to father a child should take a different drug as prescribed by the doctor to speed up removal of teriflunomide from the body. (See also How to Use section.)

This medication must not be used during pregnancy. It may harm an unborn baby. Before starting this medication, women of childbearing age must have a negative pregnancy test. Discuss the use of reliable forms of birth control (such as birth control pills, intrauterine device-IUD) with your doctor. If you become pregnant or think you may be pregnant, tell your doctor right away. See also Warning section.

This drug may pass into breast milk and could have undesirable effects on a nursing infant. Breastfeeding is not recommended while using this drug. Consult your doctor before breastfeeding.