Sudden Hair Loss
• Telogen effluvium triggered by specific event
• Discuss the triggering event
Gradual Hair Loss
• Alopecia areata
• Androgenetic alopecia
• Scarring alopecias
• Diagnosis relies on history, exam findings, and a pull test showing a high telo gen-to-anagen ratio.
• Consider family history and patterns.
• Referral if scaring is suspected.
Diffuse Hair Loss
• Alopecia totalis if more than scalp is involved
• Systemic disease (e.g., hypothyroidism, iron deficiency, other nutritional disorder)
• Referral recommended
• Lab tests, such as CBC and TSH, depend on history and physical exam findings, which are typically diagnostic.
Patchy Hair Loss
• Alopecia areata, trichotillomania
• Tinea capitis
• History and exam findings are diagnostic.
• Obtain fungal cultures if itching, scaling, pustules, or lymphadenopathy occur.
Male/Female Pattern
• Androgenetic alopecia
• History and exam findings are diagnostic; scalp appears normal.
History of Anxiety or Psychiatric Disorders
• Trichotillomania
• Obtain psychiatric history. Patient may refrain disclosure of hair-pulling. Pattern and appearance of hair are diagnostic.
Extensive Hair Product Use or Tght Hair Styles
• Trichorrhexis nodosa
• History and exam findings are diagnostic; broken hairs visible under magnification.
Medication Use
• Several types, often telogen effluvium
• If a specific medication is suspected, a trial discontinuation is reasonable.
Physical or Emotional Trauma
• Telogen effluvium
• History and exam findings are diagnostic; scalp appears normal, and hair loss may be subtle.
Skin Condition
• Scarring alopecia and tinea capitis; most nonscarring alopecias feature a relatively normal scalp.
• History and exam findings are diagnostic.
Systemic Symptoms
• Systemic disease related
• Lab testing depends on history and exam findings.
