Hormonal acne has one distinguishing characteristic: it appears predominantly on the lower third of the face — jawline, chin, neck — and follows predictable cycles related to the menstrual cycle, stress, or hormonal changes. This distribution isn't random — it's the topographical reflection of how androgens act on the sebaceous glands of these zones.

The Mechanism: Why Androgens Cause Acne

Androgens (testosterone, DHEA, DHT) directly stimulate sebaceous glands to produce more sebum. The glands of the lower third of the face have a higher density of androgenic receptors — which is why hormonal acne appears there and not on the forehead.

Stress increases cortisol, which in turn stimulates DHEA production — an adrenal androgen. This is why acne worsens in high-stress weeks even without cyclical hormonal changes.

Topical Actives With Evidence for Hormonal Acne

• Niacinamide at 4–5% — anti-inflammatory, regulates sebum via sebaceous lipid inhibition, mildly antibacterial
• Salicylic acid (BHA) — lipid-soluble, penetrates the pore, reduces comedones and closed comedones
• Prebiotics — rebalance C. acnes without destroying the entire flora
• Azelaic acid — antibacterial + anti-inflammatory + depigmenting for post-acne scars

What Worsens Hormonal Acne (and Appears to Help)

• Aggressive cleansing — increases dehydration that reactivates compensatory sebum
• Very occlusive products on jawline/chin — trap sebum and increase comedones
• Over-exfoliation — disrupts the barrier and increases inflammation