🐇 Hyperthyroidism Explained

This page explains the symptoms and causes of hyperthyroidism, how it is diagnosed with blood tests, and the treatment options used to bring an overactive thyroid back to normal.

Hyperthyroidism means your thyroid is making too much thyroid hormone.

It is the opposite of hypothyroidism.

High Thyroid – When the Thyroid Is Too Fast 

🔎 What Is Hyperthyroidism? 

“Hyper” means overactive or too much.

So hyperthyroidism means:

➡ Your thyroid is working too hard and too fast

When this happens, your body’s systems speed up.

🧠 What Happens in the Body 

With too much thyroid hormone:

• Metabolism speeds up
  
  

• Heart rate increases
  
  

• Body temperature rises
  
  

• Energy feels “nervous” or jittery
  
  

• Digestion moves faster
  
  

• Sleep can become difficult
  
  

It can feel like your body is stuck in fast-forward.

📌 Most Common Causes 

The most common causes of hyperthyroidism are:

1) Graves’ Disease

• An autoimmune condition
  
  

• The immune system overstimulates the thyroid
  
  

• Most common cause overall
  
  

2) Thyroid Nodules

• A “hot” nodule that makes extra hormone
  
  

3) Thyroiditis

• Temporary inflammation of the thyroid
  
  

4) Too Much Thyroid Medication

• Taking more hormone than the body needs
  
  

5) Excess Iodine or Certain Medicines

• Less common, but possible

😰 Common Symptoms of Hyperthyroidism 

Because everything speeds up, symptoms often include:

• Feeling anxious or nervous
  
  

• Fast or pounding heartbeat
  
  

• Trouble sleeping
  
  

• Unexplained weight loss
  
  

• Feeling hot all the time
  
  

• Sweating more than usual
  
  

• Shaky hands or tremors
  
  

• Irritability or mood swings
  
  

• Diarrhea or frequent bowel movements
  
  

• Muscle weakness
  
  

• Thinning hair
  
  

• Lighter or irregular periods
  
  

Many people describe feeling like they’ve had “too much caffeine” all the time.

👁 Special Symptoms in Graves’ Disease 

With Graves’ disease, some people also develop:

• Bulging or irritated eyes
  
  

• Eye dryness or redness
  
  

• Sensitivity to light
  
  

• Double vision
  
  

This is called thyroid eye disease.

🧪 How Hyperthyroidism Is Diagnosed 

Diagnosis is based on blood tests.

The Typical Pattern Is:

• Low TSH
  
  

• High Free T4 and/or High Free T3
  
  

This confirms hyperthyroidism.

Additional Tests That May Be Done

• TSI or TRAb antibodies (for Graves’ disease)
  
  

• Thyroid ultrasound
  
  

• Radioactive iodine uptake scan
  
  

• Heart rate and blood pressure checks

🧩 What “Subclinical Hyperthyroidism” Means 

Sometimes tests show:

• Low TSH
  
  

• Normal Free T4 and T3
  
  

This is called subclinical hyperthyroidism.

It can still cause symptoms and may need monitoring or treatment depending on:

• Age
  
  

• Heart health
  
  

• Bone health
  
  

• Symptoms

💊 Treatment Options for Hyperthyroidism 

Unlike low thyroid, hyperthyroidism has several different treatment options. 

1) Anti-Thyroid Medications

Medicines such as:

• Methimazole
  
  

• Propylthiouracil (PTU)
  
  

These help slow down the thyroid.

2) Beta Blockers

These don’t fix the thyroid itself, but they help control symptoms like:

• Fast heartbeat
  
  

• Tremors
  
  

• Anxiety

3) Radioactive Iodine Treatment

• Gradually shrinks the thyroid
  
  

• Often leads to hypothyroidism later
  
  

• Very common long-term treatment

4) Surgery

• Removal of part or all of the thyroid
  
  

• Used in certain situations

🕒 Is Hyperthyroidism Temporary or Permanent? 

It depends on the cause.

• Thyroiditis can be temporary
  
  

• Graves’ disease is usually long-term
  
  

• Medication-related hyperthyroidism can be reversed
  
  

Your doctor determines this based on tests and history.

❗ Possible Complications if Untreated 

Untreated hyperthyroidism can lead to:

• Heart rhythm problems
  
  

• Bone thinning (osteoporosis)
  
  

• Muscle weakness
  
  

• Severe symptoms called “thyroid storm”
  
  

That’s why proper diagnosis and treatment are important.

🧭 What Usually Happens Next 

If you are diagnosed with hyperthyroidism, typical next steps are:

1. Identify the cause
   
   

2. Start symptom control (often beta blockers)
   
   

3. Choose a long-term treatment plan
   
   

4. Monitor blood tests regularly

🔑 Big Takeaways 

Hyperthyroidism = overactive thyroid

It speeds up many body systems

Diagnosis usually shows low TSH and high T4/T3

Several effective treatment options exist

Most people do very well once treated

Coming Up Next 

The next page will focus on the most common cause of low thyroid:

➡ Hashimoto’s Disease Explained