What is the treatment for hair loss due to hypothyroidism?

Treatment of Hair Loss Due to Hypothyroidism

The treatment for hair loss caused by hypothyroidism is levothyroxine replacement therapy to normalize thyroid hormone levels, which will typically resolve the hair loss as thyroid function is restored. 1, 2, 3

Primary Treatment Approach

Levothyroxine monotherapy is the definitive treatment for hypothyroidism-related hair loss, as hair loss is a direct manifestation of thyroid hormone deficiency that resolves with adequate hormone replacement. 2, 3, 4

Initial Dosing Strategy

• Start levothyroxine at 1.5-1.8 mcg/kg/day for most adult patients to achieve rapid normalization of thyroid function 5
• Use lower starting doses (12.5-50 mcg/day) in patients over 60 years old or those with known/suspected coronary artery disease 5
• Take as a single daily dose on an empty stomach, one-half to one hour before breakfast with a full glass of water 2

Monitoring and Dose Adjustment

• Check TSH levels 6-8 weeks after initiating treatment or after any dose change 3
• Target TSH range of 0.4-4.0 mIU/L (some sources suggest 0.5-2.0 mIU/L for optimal symptom control) 4, 6
• Monitor annually once TSH is at goal to avoid both under-treatment and over-treatment 3

Expected Timeline for Hair Loss Resolution

Partial hair loss may occur during the first few months of levothyroxine therapy, but this is usually temporary as the body adjusts to normalized thyroid hormone levels. 2 Hair regrowth typically begins once thyroid function normalizes, though complete resolution may take several months as the hair growth cycle restores. 1, 3

Critical Management Considerations

Medication Interactions to Avoid

Do not take levothyroxine within 4 hours of iron supplements, calcium supplements, or antacids, as these agents significantly decrease levothyroxine absorption and can prevent adequate treatment of hypothyroidism and its symptoms, including hair loss. 2

When Hair Loss Persists Despite Treatment

If hair loss continues despite normalized TSH levels:

• Verify medication compliance and proper administration technique 4
• Check for malabsorption issues or drug interactions that may be preventing adequate levothyroxine absorption 4
• Reassess for other causes of hair loss beyond hypothyroidism, as multiple conditions can cause alopecia 5
• Consider referral to endocrinology if TSH remains elevated despite apparently adequate dosing 5

Common Pitfalls

• Avoid over-replacement: Excessive levothyroxine increases risk of atrial fibrillation and osteoporosis without improving symptoms 4
• Do not use thyroid hormone for weight control or hair loss in euthyroid patients: Levothyroxine is not indicated as primary therapy for hair loss in patients with normal thyroid function 2
• Ensure lifelong therapy: Hypothyroidism typically requires permanent hormone replacement; discontinuation will result in recurrence of all symptoms including hair loss 2, 3

Special Populations

Pregnant women with hypothyroidism should increase their levothyroxine dose by 30% (taking one extra dose twice weekly) as soon as pregnancy is confirmed, as inadequate treatment can affect both maternal and fetal outcomes. 5