Causes of rosacea

The exact cause of rosacea is unknown. However experts think it may be caused by a number of related factors.

These factors are outlined below.

Blood vessel abnormalities

Many dermatologists (skin specialists) believe that 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 is not known what causes these abnormalities. However, damage of the skin matrix (collagen) from sunlight may be responsible for dilation of skin vessels which leads to redness, thread veins and inflammation.

Demodex folliculorum

Demodex folliculorum is a microscopic mite (tiny insect) that may contribute to rosacea. These mites usually live harmlessly on human skin, but higher numbers of mites have been found on people with rosacea. However, it is uncertain whether the mite is a cause or an effect of rosacea.

Helicobacter pylori bacteria

Helicobacter pylori bacteria, found in the digestive system, have been suggested as a possible cause of rosacea, although the link is not proven. The bacteria may stimulate production of a protein called bradykinin, known to cause blood vessels to expand.

Chemicals and ngested agents

Alcohol, caffeine, hot beverages, spicy foods, and medicines (such as amiodarone, topical steroids, oral steroids, and high doses of vitamins B-6 and B-12) may trigger flushing in patients with rosacea. However, there is no good quality evidence to support these factors as a cause of rosacea.


Rosacea seems to run in families. However, it is not known which genes are involved or how they are passed on.

Triggers of rosacea

Most people who have rosacea notice certain triggers make their symptoms worse. Different people can have different triggers, but most commonly reported ones include:

  • exposure to sunlight
  • stress
  • hot weather
  • exposure to wind
  • strenuous exercise
  • alcohol
  • hot baths
  • cold weather
  • spicy foods
  • humidity
  • caffeine (found in tea, coffee and cola)
  • dairy products
  • acute (short-term) medical conditions, such as a cold or fever (high temperature)
  • chronic (long-term) medical conditions, such as high blood pressure (hypertension)
  • vasodilatory medicines, which are often used to treat high blood pressure
Content supplied by NHS ChoicesThe Information Standard - Certified Member

Last revised: 3 July 2012

Next review: 3 July 2014