Washington, July 10 - More than 90 percent of dentists are of the view that patients complaining of dry mouth take multiple medications, says a nationwide survey conducted by the Academy of General Dentistry (AGD).

Dry mouth, or xerostomia, is caused by a decrease in salivary function. It affects approximately one in four Americans, placing more than 25 percent of people at risk for tooth decay.

'The number of xerostomia cases has increased greatly over time because people are taking more and more medications,' said Cindy Kleinman, member, AGD.

'General dentists are seeing this trend in their offices, which is why they are trying to learn all they can about this condition. The more they know, the better they will be at diagnosing and treating patients,' she added.

There are more than 400 prescription and non-prescription drugs associated with xerostomia, according to Raymond K. Martin, member AGD.

'Anti-depressants, pain-killers, diuretics, antihistamines, tranquilisers and anti-hypersensitives can all contribute to dry mouth,' said Martin.