Hypothyroidism (Underactive Thyroid)

Hypothyroidism, also called underactive thyroid, is a condition in which the thyroid gland doesn't produce enough thyroid hormone. The thyroid is a small, butterfly-shaped gland in the front of your neck that produces hormones that regulate metabolism, energy, and many body functions.

When the thyroid doesn't produce enough hormone, many body functions slow down. Hypothyroidism is common, especially in women and older adults. It's usually easily treated with daily medication, but it requires lifelong management.

Symptoms develop slowly and may be mistaken for other conditions:

Common Symptoms:

• Fatigue: Feeling tired and sluggish
• Weight gain: Unexplained weight gain
• Cold intolerance: Feeling cold when others don't
• Constipation: Slowed digestion
• Dry skin: Skin may be dry and rough
• Hair loss: Thinning hair or hair loss
• Muscle weakness: Weakness and aches
• Joint pain: Aches and stiffness
• Depression: Low mood
• Memory problems: Difficulty concentrating
• Slow heart rate: Bradycardia
• Hoarse voice: Voice changes
• Puffy face: Facial swelling
• Elevated cholesterol: High cholesterol levels

Symptoms may be mild or severe and vary between individuals.

Seek emergency care if you have:

• Severe confusion
• Extreme fatigue
• Difficulty breathing
• Very low body temperature
• Loss of consciousness

These could indicate myxedema coma, a rare but serious complication.

Managing hypothyroidism involves:

1. Take Medication as Prescribed:

   • Take thyroid medication daily
   • Take on empty stomach (usually morning)
   • Don't skip doses
   • Take at same time each day
   • Don't stop without doctor's approval

2. Regular Monitoring:

   • Regular blood tests to check levels
   • Follow-up appointments
   • Report symptoms to doctor
   • May need dose adjustments

3. Healthy Lifestyle:

   • Balanced diet
   • Regular exercise
   • Adequate sleep
   • Stress management

4. Medication Interactions:

   • Some medications affect absorption
   • Iron supplements
   • Calcium supplements
   • Some antacids
   • Space medications appropriately

5. Diet Considerations:

   • Generally no special diet needed
   • Iodine is important (usually adequate in diet)
   • Some foods may affect medication (discuss with doctor)
   • Maintain healthy weight

6. Manage Symptoms:

   • Address fatigue with rest and activity balance
   • Manage weight with diet and exercise
   • Treat dry skin with moisturizers
   • Address depression if present

• Severe confusion or drowsiness
• Extreme fatigue
• Very low body temperature
• Difficulty breathing
• Loss of consciousness

• New or worsening symptoms
• Symptoms not improving with treatment
• Need to adjust medication
• Questions about treatment
• Planning pregnancy
• Side effects from medication

• Symptoms well-controlled
• Following treatment plan
• Regular monitoring scheduled
• No new concerns

Diagnosing hypothyroidism involves:

1. Medical History and Physical Exam:

   • Symptom assessment
   • Family history
   • Physical examination
   • Check for goiter (enlarged thyroid)

2. Blood Tests:

   • TSH (thyroid-stimulating hormone): Primary test
   • T4 (thyroxine): Thyroid hormone level
   • T3 (triiodothyronine): Active thyroid hormone
   • Thyroid antibodies: If autoimmune cause suspected

3. Additional Tests (if needed):

   • Thyroid ultrasound
   • Thyroid scan
   • Other hormone tests

Normal Ranges (may vary by lab):

• TSH: Usually 0.4-4.0 mIU/L
• Elevated TSH with low T4 indicates hypothyroidism

Treatment involves replacing the missing thyroid hormone:

1. Thyroid Hormone Replacement:

   • Levothyroxine: Synthetic T4 (most common)
   • Taken daily, usually in morning
   • On empty stomach
   • Same time each day

2. Dosage:

   • Based on weight, age, and severity
   • Started at low dose
   • Gradually increased
   • Adjusted based on blood tests

3. Monitoring:

   • Blood tests every 6-12 weeks initially
   • Then every 6-12 months once stable
   • TSH is primary monitoring test
   • May need dose adjustments

4. Lifestyle Support:

   • Healthy diet
   • Regular exercise
   • Adequate sleep
   • Stress management

5. Treating Underlying Cause (if applicable):

   • Hashimoto's disease (autoimmune) is most common
   • Other causes may need specific treatment

Most cases of hypothyroidism cannot be prevented, but:

• Adequate Iodine: Ensure sufficient iodine in diet (usually not a problem)
• Regular Check-ups: Especially if at risk
• Know Family History: Thyroid disease can run in families
• Monitor After Treatment: If treated for hyperthyroidism or thyroid cancer
• Early Detection: Get tested if symptoms develop

In hypothyroidism:

1. Reduced Hormone Production: Thyroid doesn't produce enough hormone
2. Metabolic Slowdown: Body functions slow down
3. Energy Production: Reduced energy production
4. Symptom Development: Various symptoms appear

Causes:

• Hashimoto's disease: Autoimmune condition (most common)
• Thyroid surgery: Removal of thyroid
• Radiation therapy: For head/neck cancers
• Medications: Some medications can cause it
• Congenital: Present at birth (rare)
• Iodine deficiency: Rare in developed countries
• Pituitary problems: Rare cause

• More common in women
• May develop after pregnancy
• May affect menstrual cycles
• Important during pregnancy (needs monitoring)

• More common with age
• Symptoms may be mistaken for aging
• May have other health conditions
• May need lower medication doses

• Important to treat during pregnancy
• May need dose adjustments
• Regular monitoring needed
• Affects baby's development if untreated

Most cases cannot be cured but are easily managed with medication. You'll likely need to take medication for life, but with proper treatment, you can live normally.

Untreated hypothyroidism can cause weight gain. With proper treatment, metabolism normalizes and weight gain should stop. You may need to work on losing weight gained before treatment.

Symptoms usually start improving within 2-3 weeks, but it may take several months for full effect. You'll need regular blood tests to ensure the dose is correct.

No. You feel better because the medication is working. Stopping it will cause symptoms to return. You'll likely need medication for life.

There is a genetic component. If you have a family history of thyroid disease, you're at higher risk. However, it's not directly inherited in a simple way.