The exact cause of rosacea is unknown, although a number of potential factors have been suggested.
It's possible a combination of these factors may be responsible for the condition, although there isn't enough evidence to say this for certain.
Some of the main factors that have been suggested are outlined below.
Some experts believe abnormalities in the blood vessels of the face may be a major contributing factor for rosacea. This may explain symptoms of flushing, persistent redness and visible blood vessels.
It's not known what causes these abnormalities. But sun damage may be responsible for degeneration of the elastic tissue of the skin and the dilation of blood vessels.
Recent research has shown external triggers such as ultraviolet (UV) light, spicy food, alcohol (particularly red wine), exercise, stress, heat and cold can lead to theactivation of certain molecules within the skin called peptides.
Increased levels of these peptides may in turn affect the immune system ornerves and blood vessels(neurovascular system) of the skin. Activation of these systems can cause dilation of blood vessels, redness and inflammation.
Microscopic mites called demodex folliculorum usually live harmlessly on human skin, but people with rosacea have particularly large numbers, which may play a role in the condition.
It is currently uncertain whether the mite is a cause or an effect of rosacea, although someresearchers have suggested the symptoms may be caused by the skin reacting tobacteria in the mites' faeces.
Helicobacter pylori bacteria are bacteriafound in the digestive system. It's been suggested these bacteria may be a possible cause of rosacea, althougha linkhasn't been proven.
One theory is the bacteria may stimulate the production of a protein called bradykinin, which is known to cause blood vessels to expand.
Rosacea seems to be more common in families, although it's not clear which genes if any are involved or how they're passed on.
Although they're not thought to be direct causes ofthe condition, many people with rosacea find certain triggers make their symptoms worse.
Different people can have different triggers, but triggers that have been commonly reported include:
Read about rosacea, a common but poorly understood long-term (chronic) skin condition that mainly affects the face.
Read about the symptoms of rosacea, such as flushing, facial redness, visible blood vessels, and papules or pustules.
Read about the causes of rosacea. The exact cause of rosacea is unknown, although a number of potential factors have been suggested.
Treatment for rosacea aims to help keep the symptoms under control. There's currently no known cure for rosacea.
Read about self-help measures for rosacea, including avoiding triggers, skincare techniques and eyelid hygiene.
If you have rosacea, there are a number of things you can do to help keep the condition under control. Avoid triggers. Many people with rosacea notice certain triggers make their symptoms worse.