Common Causes of Scalp Itch

• The most common causes of scalp itch are an allergic reaction to soap or shampoo, contact dermatitis, which is a skin reaction to an irritant, head lice, eczema, psoriasis or tinea, which is a general term for various fungal skin afflictions often incorrectly called ringworm.
  
  

Uncommon Causes of Scalp Itch

• More uncommon causes of scalp itch include basal cell carcinoma, which is a slow-growing form of skin cancer, lupus erythematosus, seborrheic dermatitis and herpes zoster or shingles, an infectious viral infection believed to be caused by the reactivation of a previous chickenpox infection.