The cause of rosacea is not unknown. But there are various theories about its origin. The blood vessels in the face are thought to be abnormally dilated due to increased blood flow from the facial skin and/or due to an altered response pattern of the blood vessels to stimuli from within and without. This causes the blood to stop, which triggers an inflammatory reaction, resulting in redness, swelling, bumps and pustules. A change in the skin environment can also be the cause. For example, as a result of the changed skin environment, the “Demodex” mite could be a cause. This mite, which lives naturally in the sebaceous gland, does not normally cause any problems, but in rosacea the “Demodex” mite is present in large numbers and can exacerbate or maintain the inflammatory reaction. In addition to these factors, there are a number of other factors that may affect rosacea. These include: Nutrition Alcohol Medicines Temperature changes UV radiation Aggressive skin care products Stress Hormones