Cellphone addicts, beware. Using your phone for long periods of time may cause a rash to develop on your face and ears, doctors warn.

The British Association of Dermatologists (BAD) has identified a skin disorder called mobile phone dermatitis, which is an allergic reaction to a cellphone's nickel surface.

The Association cited published case studies of patients who had unexplained rashes that were later linked to the nickel in phone buttons and casings.

"Prolonged or repetitive contact with a nickel-containing phone is more likely to cause a skin reaction in those who are allergic," Dr. Graham Lowe of BAD said in a news release. "If you have had a previous reaction to a nickel-coated belt buckle or jewelry, for example, you are at greater risk of reacting to metal phones."

The dermatologists believe the condition is on the rise and, because it has only recently been identified, may be under reported.

They also warn that the rash may spread to phone users' fingers if they spend a lot of time using buttons for text messaging or surfing the web.

"The more you talk on the phone, the more you sweat, the more the nickel leeches out," dermatologist Dr. Joel DeKoven told CTV News.

U.S. researchers conducted a study earlier this year and found nickel in 10 of 22 phones from eight different manufacturers.

The researchers, from Brown University, found nickel in the menu buttons, logos and the metallic frames around the display screens.

"Given the widespread use of cellphones the presence of metal in the exterior casing of these phones and the high prevalence of nickel sensitization in the population, it is not surprising that cellphones cause allergic contact dermatitis," Dr. Lionel Bercovitch, one of the study's authors, said in a statement.

Some of the cellphone models included in the study are no longer sold while other manufacturers told CTV News they are limiting or eliminating the use nickel in their products.

Symptoms of dermatitis include a rash, flaking or itchy skin. Treatments include applying a topical steroid cream and avoiding contact with the allergen (in this case, nickel).

"If you have an allergy to nickel in your phone the best option is to get a new phone," Toronto dermatologist Dr. Sandy Skotnicki-Grant told CTV News

The British dermatologists advise anyone who develops a rash on their face to see a doctor or dermatologist right away.