Warnings health professionals are seeing an increase in health scams starring prominent doctors

Auckland University says it's concerned, after an ad ran on a major news site - featuring a sham interview with Sir Ashley Bloomfield.

The former Director-General of Health works for the university - which says his name and image have been used without his knowledge.

General Practice New Zealand chair Bryan Betty says he has also been the victim of a bogus ad.

He says patients give validity to claims when the person featured is well know, and he's incredibly concerned about what's in the products.