People with the kind of health anxiety formerly referred to as hypochondriasis used to have to go to the doctor’s office to quell their concerns. Thanks to a new crop of apps, they can now just take out a smartphone and reach a health professional anytime, from anywhere.

Studies suggest that health anxiety—more recently termed somatic symptom disorder and illness anxiety disorder—affects anywhere from less than 1 percent to as high as nearly 12 percent of the population. For some of these people, a new array of telemedicine apps like MDLive and Doctor on Demand are appealing because they take insurance and also let you pay upfront at cost of about $40 to $50 for a short video or phone consult.

Because of how easy these apps are to use, some medical experts wonder whether, over time, telemedicine apps will encounter a disproportionate number of users with health anxiety disorders. Already, these users are popping up, and the app makers are encountering the ethical question of whether they should encourage users to seek mental help.

MDLive’s chief medical affairs officer, Deborah Mulligan, says that the company’s app has 28 million registered users, and it’s likely that about 6 percent have this condition, which mirrors the proportion found in the general population.

What makes matters more complex is that with any other type of mobile technology, these people would be considered “super users” that drive revenue—the kinds of folks you want to stick around and keep using the app all the time. But in the telemedicine space, app makers may feel they should monitor this type of behavior and refer the users to mental health support services.

Mulligan spent much of her career working in emergency rooms, where she was trained to recognize the symptoms of health-related anxiety disorders, which include worrying about a disease when there’s no symptoms, experiencing high anxiety about minor aches and pains, and not feeling reassured by negative test results. She recalls one MDLive patient who exhibited all of these symptoms, and who suggested setting up regular consults to discuss a specific health condition that the patient didn’t have. After several sessions to build up trust, Mulligan recommended that the patient try MDLive’s cognitive behavioral therapy service.

“They contacted me to thank me,” she says. “It was like a weight off their shoulders.”

Doctor on Demand board member Bob Kocher says that the majority of the people who use the app are calling up about routine symptoms, like colds and the flu. He isn’t aware of patients with health-related anxiety regularly using the app to alleviate excessive fears about their symptoms. However, he thinks it’s possible that more of such patients will discover the app as it gains mainstream recognition.

“Frankly, I think there are some of these patients in the health system who haven’t found us yet,” he says. “I’m sure we’ll have board meetings someday about a patient who used us 20 times that week.”

Kocher says that app makers might make a “lot of money” through these interactions, but will have a responsibility to investigate whether the problem was solved or handled well.

One of the challenges of finding these kinds of users, experts say, is the lack of information transparency, particularly as the apps don’t share data with each other. “We don’t really know who the frequent users [of these apps] are,” says John Torous, co-director of the digital psychiatry program at Beth Israel Deaconess Center. “It’s a population that is not well characterized.”

And Doctor on Demand’s chief medical officer, Ian Tong, points out that excessive health anxiety might be challenging to monitor if patients use an array of different apps.

“You might not be able to tell unless the person was being prescribed a lot of medications,” he admits.