Apocrine Glands: Function, Location, and Secretion

Apocrine glands produce sweat containing proteins and fats. They are larger, less numerous than eccrine glands, located mainly in armpits, groin, and around nipples. Activated at puberty by androgens, they secrete a milky, viscous, initially odorless fluid. Bacteria on skin break it down, producing characteristic body odor.

Comparison with Eccrine Glands

Feature	Apocrine	Eccrine
Distribution	Axilla, groin, areola, eyelids (Moll's), ear (ceruminous)	Body-wide (palms, soles, forehead highest)
Secretory product	Milky, protein/lipid-rich	Watery, electrolytes
Activation	Puberty (androgens), emotional stress	Thermoregulation (heat, exercise)
Odor	Yes (bacterial breakdown)	No (unless bacterial overgrowth)

Clinical Note

Apocrine glands are involved in hidradenitis suppurativa (blocked follicles → inflammation). Bromhidrosis (excessive odor) treated with hygiene, topical antibiotics, botox, or surgery.