Understanding Hypothyroidism

Hypothyroidism: a closer look

No matter how much you may already know about hypothyroidism, it's important to keep learning. The better you understand it, the better prepared you are to help manage it. Take a moment to learn more below.

What is hypothyroidism?

Hypothyroidism is a condition that occurs when the thyroid gland doesn’t make enough of the thyroid hormone called thyroxine (T4). This causes the body’s system to slow down and can lead to symptoms like fatigue, feeling cold, weight gain due to fluid retention, dry skin, and hair loss. 

The role of TSH

The thyroid produces T4 as a response to the thyroid-stimulating hormone (TSH). TSH is produced by a small gland in the brain called the pituitary and can be measured by a blood test. This blood test, which measures both thyroid hormones and TSH, can be used to diagnose hypothyroidism. Let's take a closer look below.

TSH and a normally functioning thyroid

TSH and an incorrectly functioning thyroid

Looking for more info?

The Understanding and Managing Hypothyroidism guide below takes an even deeper dive into this condition, its causes, and how it's managed.

Download hypothyroidism guide

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Hypothyroidism from head to toe*

Take your time exploring this overview of hypothyroidism symptoms. Do you experience any? If so, talk to your doctor. They may want to check your T4 or TSH levels using the test described below.

*This is not a comprehensive list of symptoms.

Because these symptoms may represent conditions other than hypothyroidism, be sure to talk to your doctor.

Share your symptoms with your doctor

Helping your doctor understand your symptoms is vital to getting you the right diagnosis and treatment. Use this checklist to record any symptoms that your doctor should know about.

Download symptom checklist

The TSH test

A TSH test is used to check the level of TSH in the blood. Your TSH level can indicate if your thyroid gland is working properly.

Once you have been diagnosed with hypothyroidism and your doctor has prescribed a treatment plan, it’s important to have your TSH tested periodically to determine if any adjustments need to be made to your dose or how you take your medication.

Real Synthroid stories

Facing hypothyroidism: Elisa’s story

Elisa shares her journey, from getting diagnosed to starting—and continuing—treatment with Synthroid, and living with hypothyroidism.

Myths vs Facts

A thyroid-stimulating hormone (TSH) test is just one way to determine if you’re managing your hypothyroidism. What do you think, is this a myth or a fact?

Sorry, that's incorrect. This is a fact.

A TSH test is one way to measure how you’re doing. It’s also important to talk with your doctor about how you’re feeling and about any symptoms you’re experiencing.

See more myths vs facts

Correct! This is a fact.

A TSH test is one way to measure how you’re doing. It’s also important to talk with your doctor about how you’re feeling and about any symptoms you’re experiencing.

See more myths vs facts

Getting your thyroid hormone levels in balance

See how Synthroid can help restore your thyroid hormone levels and manage hypothyroidism.

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