Lower segment (bulb and suprabulb) Extends from base of follicle to insertion of erector pili muscle Bulb Suprabulb

Melanin Formed in pigment-producing cells (melanocytes) in hair bulb during growing (anagen) phase Melanin granules spread throughout cortex Two forms: 1-Eumelanin (brown and black hair) 2-Pheomelanin (red and blonde hair)

Eumelanin: Brown, black Gray Hair: No color Phaeomelanin: Red, Blond Hair Pigmentation

Dark Pigmented Red Pigmented

Hair Colors

Causes of Excessive Hair HirsutismHypertrichosisHyperandrogenism Idiopathic Hirsutism Late onset congenital adrenal hyperplasia Ovarian tumors Adrenal causes Pregnancy: luteoma of pregnancy Drugs

Best Scenario Same phase Same depth Dark pigment Light skin

Normal Scenario Different phase Different depth Different pigment Differing skin color

lip 1-2.5mm Arms Beard Breasts 2-4mm Legs 2-4.5mm Scalp 2-5mm Axilla 4-5mm Chest Back 5-7mm