Possible Side Effects What are the possible side effects?

Certain side effects can occur with Synthroid, and these are often the result of your body getting too much medicine, also known as overtreatment. So it’s important to talk with your doctor about any symptoms you’re experiencing.

Symptoms of overtreatment may include*

*This is not a comprehensive list of side effects. Please see Full Prescribing Information for a complete list of side effect information and talk to your doctor.

Keep food and medication interactions in mind

Certain food and medications can interfere with the way your body absorbs or processes Synthroid. Let your doctor know about any changes.

See a list of food and medication interactions

Record your symptoms

Use this journal to track your symptoms and share with your doctor at your next appointment.

Download symptom journal

Real Synthroid stories

Meet Wendy

Learn about Wendy's surprise diagnosis and how Synthroid became a trusted part of her routine.

Commonly asked questions

Continue learning about Synthroid

From information on hypothyroidism to guides on how to talk to your doctor, explore our collection of downloadable resources to help you understand the benefits of Synthroid.