The cause of rosacea is unknown, but it could be due to an overactive immune system, heredity, environmental factors or a combination of these. Rosacea is not caused by poor hygiene and it's not contagious.
Flare-ups might be triggered by:
• Hot drinks and spicy foods
• Red wine and other alcoholic beverages
• Temperature extremes
• Sun or wind
• Emotions
• Exercise
• Drugs that dilate blood vessels, including some blood pressure medications
• Some cosmetic, skin or hair care products
Risk factors:
Anyone can develop rosacea. But you may be more likely to develop it if you:
• Are female
• Have skin that burns easily in the sun
•Are over age 30
•Smoke
•Have a family history of rosacea
Courtesy: Mayo Clinic