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What Is Rosacea?

Symptoms & Causes of Rosacea

The symptoms of rosacea

Rosacea can cause redness, similar to that of a blush or sunburn. The flushing occurs when an increased amount of blood flows through vessels at a fast rate, and the vessels expand to accommodate the flow. The redness might become more noticeable and persistent as the disease progresses. Some people notice that their facial skin becomes increasingly dry.

Rosacea-related pimples, which often occur as the disease has progressed, are different from those caused by acne, because blackheads and whiteheads (known as comedones) rarely appear. Rather, people who have rosacea have visible small blood vessels and their pimples — some containing pus — appear as small, red bumps.

Some with rosacea notice red lines, telangiectasia (tell-an-jek-taze-yah), which appear when they flush. This is because the small blood vessels of the face become enlarged and show through the skin. These red lines usually appear on the cheeks — especially when the overall redness diminishes.

Nasal bumps, a condition called rhinophyma (rye-no-feye-muh), are a common symptom, especially in untreated rosacea. Men are more likely to experience the small, knobby bumps on the nose, and as the number of bumps increases, the nose and cheeks might appear swollen.

About half the people who have rosacea get it around the eyes and on the eyelids. They might experience burning and grittiness of the eyes (known as conjunctivitis). Their eyes can also become red and bloodshot, and their vision can become blurry. In rare circumstances, if the condition goes untreated, it can lead to serious eye complications.

A 2002 survey conducted by the National Rosacea Society indicated that some people with rosacea suffer physical symptoms, such as facial burning, stinging or itching. Nineteen percent of the 1,628 patients surveyed said their symptoms occurred beyond the face, on the neck, chest, scalp or ears.

Theories about the causes of rosacea

While the precise cause of rosacea remains a mystery, researchers believe that heredity and environmental factors are to blame. One possible explanation given is that something causes the blood vessels to swell. The result, these scientists believe, is the flushing and redness characteristic of rosacea.

Another theory is that a mite that lives in hair follicles, called Demodex folliculorum, could be a cause of rosacea. The belief is that the mites, which clog oil glands, lead to the inflammation seen in rosacea. Others believe that a bacterium that causes intestinal infection, called Helicobacter pylori, might be a cause. The immune system also has been implicated as playing a role in rosacea's development.

Who gets rosacea?

Adults, especially those between 30 and 50 years of age, are the most likely to suffer from rosacea. It occurs most often in people with lighter skin, such as those with blonde hair and blue eyes, but can affect people of any skin type. And while women are afflicted more often than their male counterparts, men frequently get more severe forms of rosacea.

When people with rosacea think about their pasts, they often remember flushing or blushing more easily than most. In many cases, rosacea is passed on in families. Some equate rosacea with alcoholism, and while drinking alcohol can worsen its symptoms, even those who don't drink can develop rosacea.