👶 Thyroid Problems in Children & Teens Explained

Learn how thyroid problems can affect children and teenagers, common symptoms to watch for, how thyroid issues are diagnosed, and how treatment helps support normal growth and development.

How Thyroid Issues Affect Younger People

Thyroid problems don’t only happen to adults.

Children and teenagers can also develop thyroid conditions—and they can look a little different than in adults.

This page explains what parents and teens need to know.

🔎 Can Kids Really Have Thyroid Problems?

Yes.

Thyroid conditions can happen at any age, including:

• Infants
  
  

• Young children
  
  

• Preteens
  
  

• Teenagers
  
  

In fact, thyroid issues are one of the more common hormone problems seen in kids.

🧠 Why the Thyroid Is Important in Growing Kids

Thyroid hormones are especially important in children because they help control:

• Growth
  
  

• Brain development
  
  

• Puberty
  
  

• Energy levels
  
  

• Learning and focus
  
  

That’s why thyroid problems in kids need to be taken seriously.

🐢 Hypothyroidism in Children (Low Thyroid)

Low thyroid is the most common thyroid issue in kids.

The most common cause is:

➡ Hashimoto’s disease, just like in adults.

Symptoms Can Look Different in Kids

Instead of just fatigue, children may show:

• Slowed growth
  
  

• Delayed puberty
  
  

• Trouble concentrating
  
  

• Poor school performance
  
  

• Weight gain
  
  

• Tiredness
  
  

• Constipation
  
  

• Feeling cold
  
  

• Mood changes
  
  

• Dry skin or hair loss
  
  

Sometimes the main sign is simply:

➡ Not growing as expected

🐇 Hyperthyroidism in Children (High Thyroid)

Overactive thyroid is less common in kids but does happen.

The most common cause is:

➡ Graves’ disease

Symptoms in Children and Teens

These may include:

• Nervousness or anxiety
  
  

• Trouble sleeping
  
  

• Weight loss
  
  

• Fast heartbeat
  
  

• Shaky hands
  
  

• Trouble focusing
  
  

• Irritability
  
  

• Declining school performance
  
  

• Heat intolerance
  
  

Parents sometimes mistake these symptoms for stress or behavior issues.

👶 Congenital Hypothyroidism (In Babies)

Some babies are born with thyroid problems.

This is called:

➡ Congenital hypothyroidism

Important 

In the U.S. and many countries:

• All newborns are screened for thyroid problems at birth
  
  

• This is part of routine newborn testing
  
  

• Early treatment prevents developmental problems
  
  

Thanks to screening, serious complications are now rare.

🧪 How Thyroid Problems Are Diagnosed in Kids

Diagnosis uses the same basic tests as adults:

• TSH
  
  

• Free T4
  
  

• Sometimes Free T3
  
  

• Thyroid antibody tests
  
  

Doctors also pay close attention to:

• Growth charts
  
  

• Puberty development
  
  

• School and behavior changes

🩺 Treatment in Children

Treatment is similar to adults but carefully adjusted for age and size.

For Hypothyroidism

• Levothyroxine is used
  
  

• Doses are based on weight
  
  

• Regular blood tests are needed
  
  

• Growth and development are monitored
  
  

With proper treatment, children grow and develop normally.

For Hyperthyroidism

Treatment may include:

• Anti-thyroid medications
  
  

• Beta blockers
  
  

• Sometimes radioactive iodine or surgery in older teens

🧩 Special Concerns in Teens

In teenagers, thyroid problems can affect:

• Puberty timing
  
  

• Mood and emotions
  
  

• Sports performance
  
  

• Energy levels
  
  

• School focus
  
  

• Menstrual cycles in girls
  
  

Because of this, thyroid testing is often considered when teens have unexplained changes.

🕒 Monitoring Over Time

Children with thyroid disease usually need:

• More frequent checkups than adults
  
  

• Regular lab testing
  
  

• Dose adjustments as they grow
  
  

Thyroid needs change as kids get bigger.

❗ When Parents Should Ask for Testing

Consider asking about thyroid tests if a child has:

• Slowed or stopped growth
  
  

• Unexplained weight changes
  
  

• Extreme fatigue
  
  

• Trouble concentrating
  
  

• Big changes in mood or behavior
  
  

• Delayed or very early puberty
  
  

• A visible neck swelling

🧭 What Usually Happens Next

If a thyroid problem is suspected, the usual steps are:

1. Blood tests
   
   

2. Possible ultrasound
   
   

3. Referral to a pediatric endocrinologist
   
   

4. Starting treatment if needed
   
   

5. Regular monitoring
   
   

With proper care, most kids do extremely well.

🔑 Big Takeaways

Thyroid problems can happen at any age

Symptoms in kids may be different than in adults

Growth and development are key clues

Testing and treatment are very effective

Early diagnosis makes a big difference

Coming Up Next

The next page will help pull everything together:

➡ Understanding Your Thyroid Lab Results (Putting It All Together)