A study published last year in The Journal of the American Academy of Dermatology found that dermatologists in 11 American cities and one county offered faster appointments to a person calling about Botox than for someone calling about a changing mole, a possible sign of skin cancer.

And dermatologists nationwide are increasingly hiring nurse practitioners and physicians’ assistants, called physician extenders, who primarily see medical patients, according to a study published earlier this year in the same journal.

“What are the physician extenders doing? Medical dermatology,” Dr. Allan C. Halpern, chief of dermatology at Memorial Sloan-Kettering Cancer Center in Manhattan, said in a melanoma lecture at a dermatology conference this year. “What are the dermatologists doing? Cosmetic dermatology.”

There are no published studies showing that the rise of beauty procedures has caused harm to medical dermatology patients. If patients with skin problems have difficulty getting appointments, it is because over the last 30 years the demand to see skin doctors has far outstripped the number of physicians trained in the specialty, said Dr. Jack S. Resneck Jr., an assistant professor of dermatology at the medical school of the University of California, San Francisco.

Dr. Resneck, who researches professional issues in dermatology, said about 10,500 dermatologists now practiced in the United States, the majority devoting little time to vanity medicine.

Even so, dermatologists perform several million beauty treatments annually, according to estimates by the American Society for Dermatologic Surgery, including more than two million anti-wrinkle injection treatments last year — an increase of 130 percent over 2005.

Several patients interviewed for this article said that they believed the dermatologists they visited for medical care treated them as potential cosmetic consumers. Dianne Ryan, who works for an airline in Dallas, went to a dermatologist in her insurance network three years ago after her husband pointed out a mole growing on the side of her foot, she said. The doctor dismissed the mole as benign, she said, but recommended she buy his brand of bleaching cream for pigmentation on her face.