What are the causes and treatments of hair loss?

Hair Loss: Causes and Treatment Options

Hair loss can be caused by various factors including androgenetic alopecia, alopecia areata, telogen effluvium, nutritional deficiencies, hormonal imbalances, and other medical conditions, with treatment options ranging from topical minoxidil and intralesional corticosteroids to systemic therapies depending on the specific diagnosis.

Types and Causes of Hair Loss

Non-Scarring Alopecias

1. Androgenetic Alopecia (Pattern Hair Loss)

   • Most common form of hair loss 1
   • Genetic predisposition with hormonal influence (DHT)
   • Typically affects the vertex of scalp in men and diffuse thinning in women 2

2. Alopecia Areata

   • Chronic inflammatory condition affecting hair follicles 3
   • Presents as patches of hair loss on scalp or any hair-bearing skin
   • May progress to total scalp hair loss (alopecia totalis) or complete body hair loss (alopecia universalis) 3
   • Autoimmune etiology with T-lymphocyte mediation 3

3. Telogen Effluvium

   • Diffuse hair shedding caused by physiological or emotional stress 4
   • Self-limited once precipitating cause is removed
   • Common triggers: childbirth, severe illness, medications, nutritional deficiencies 5

4. Anagen Effluvium

   • Abnormal diffuse hair loss during growth phase
   • Commonly caused by chemotherapy or toxic exposures 4

5. Other Causes

   • Trichotillomania (compulsive hair pulling) 3
   • Tinea capitis (fungal infection) 3
   • Traction alopecia (from tight hairstyles) 4
   • Hormonal imbalances (thyroid disorders, PCOS) 5
   • Nutritional deficiencies (iron, zinc, vitamin D) 6

Diagnostic Approach

Key Diagnostic Tools

1. Clinical Examination

   • Pattern of hair loss (diffuse, patchy, or patterned)
   • Presence of inflammation or scarring
   • Exclamation mark hairs (in alopecia areata) 3

2. Specialized Tests

   • Pull test: assesses active shedding 2
   • Trichoscopy: examines scalp and hair follicles in detail 2
   • Hair count: measures number of hairs in specific area 2

3. Laboratory Testing (when indicated)

   • Thyroid function tests
   • Iron studies (ferritin)
   • Vitamin D and zinc levels 2
   • Hormonal evaluation for suspected androgenic causes 5

4. Skin Biopsy

   • May be necessary in unclear cases or suspected scarring alopecia 3

Treatment Options

For Androgenetic Alopecia

1. Topical Minoxidil

   • FDA-approved treatment
   • 5% solution for men, applied twice daily 7
   • Results may be seen in 2-4 months with continued use 7
   • Hair loss resumes if treatment is discontinued 7

2. Oral Finasteride

   • For male pattern hair loss
   • 5-alpha-reductase inhibitor that blocks DHT production 5

For Alopecia Areata

1. Limited Patchy Hair Loss

   • Intralesional corticosteroid injections (first-line) 2
   • Topical corticosteroids (alternative if injections not tolerated) 2
   • Consider no treatment due to high spontaneous remission rate (80% within 1 year for limited patches) 2

2. Extensive Hair Loss

   • Contact immunotherapy with diphenylcyclopropenone (DPCP) - 50-60% response rate 2
   • Topical minoxidil 5% (limited efficacy, 32-33% response rate) 2
   • Systemic options for severe cases:
     • Methotrexate (15-25 mg/week) with or without prednisolone 2
     • Sulfasalazine (alternative systemic option) 2
     • Cyclosporine (limited evidence for severe disease) 2

For Telogen Effluvium

• Identify and remove the triggering factor 4
• Typically self-resolving once cause is addressed
• Nutritional supplementation if deficiencies are identified 6

For Other Types

• Tinea capitis: Oral antifungal therapy 4
• Traction alopecia: Reduce tension on hair, change hairstyling practices 4
• Trichotillomania: Behavioral therapy and psychiatric treatment 4

Non-Pharmacological Approaches

1. Psychological Support

   • Hair loss can cause significant psychological distress 2
   • Consider counseling and referral to patient support groups 3, 2

2. Cosmetic Options

   • Wigs or hairpieces for extensive hair loss 3, 2
   • Hair systems and camouflage products 2

3. Nutritional Considerations

   • Mediterranean diet rich in antioxidants and anti-inflammatory components 6
   • Address specific nutritional deficiencies if present 6

4. Emerging Treatments

   • Platelet-rich plasma (PRP) injections for androgenetic alopecia 3
   • Autologous platelet concentrates to induce proliferation of dermal papilla 3

Special Considerations

• Children with alopecia areata have limited treatment options as intralesional steroids are often poorly tolerated 3
• Women should not use 5% minoxidil solution as studies show it works no better than 2% solution and may cause unwanted facial hair growth 7
• Continuous use of treatments is necessary to maintain results; discontinuation leads to reversal of benefits 7

Remember that hair loss treatment requires patience, as hair typically grows only 1/2 to 1 inch per month, and results may take 2-4 months to become visible 7.