What if you could text a doctor with a medical question at any time of day and get a quick, thoughtful response? No more haphazard Googling (swollen feet allergies; tick stuck in ear access to brain?). No more sifting through random message boards. No more WebMD algorithms suggesting that a vague stomachache might be the first sign of a terminal skin disorder.

As a patient, I’d say that sounds great. As a doctor, I’d say that sounds at best unsustainable, and at worst disastrous. The average primary-care physician has about 2,300 patients. He or she would never sleep. But Ron Gutman, a Silicon Valley entrepreneur, would say that’s a business opportunity. Since he founded HealthTap four years ago, the Web site has grown into an interactive community of more than 60,000 licensed U.S. physicians, who answer user questions for free. More than 10 million people visit the site every month. Now the company has added a service called Prime, whereby a subscriber can talk immediately with a licensed doctor by phone, tablet, or computer; using voice, text, or video; at any time of day or night; as many times as he or she might like; in sickness and in health, for better or for worse. For this, a person pays $99 a month.

Is this a vanity service for wealthy hypochondriacs, or a harbinger of a coming revolution in health-care delivery? Possibly both. If some basic needs were addressed remotely, doctors could focus on more dire cases during their busy office hours. Patients could ask simple questions without needing to take an afternoon off work for an office visit. As of last year, only 12 percent of Americans had ever texted or e-mailed with a doctor, according to a survey conducted for The Atlantic. But about a third of people under 30 were open to having their primary communication with their doctors be online.

HealthTap is not, at least for now, trying to take over for anyone’s doctor. It is instead trying to supplement standard primary care. Specifically, it is trying to sell you on the idea of not ever having to wait for health-care advice. Upon hearing the story of an untimely fall from a horse or seeing a photo of a child’s post-water-park rash, the doctor on call might tell you to sit tight, or make an appointment to see someone in person, or run to the ER.

Doctors on HealthTap are paid for the time they spend conducting one-on-one consultations with patients, but they aren’t paid for answering questions submitted by anonymous users via the Web site. Why do they do it? “I think doctors are great people, in general,” Gutman told me. Being a doctor, I found that explanation reassuring. But physicians also participate in HealthTap for reasons not unlike the ones that motivate restaurants to post professional photos on Yelp and the CIA to join Twitter: they want to gain credibility and construct the dreaded but increasingly necessary online presence. Online presence is mentioned nowhere in the Hippocratic oath. But it can, Gutman says, help doctors “build a name and get speaking engagements, or just advance their careers.”

One doctor with an enviable online presence is Keegan Duchicela. HealthTap’s doctor-rating system gives him five out of five stars; he is also ranked first among HealthTap doctors nationwide for his knowledge of “insurance” and third for “abscessed tooth.” His profile boasts that his answers have been corroborated by other doctors 5,803 times, that patients have given him “thanks” 12,555 times, and that he has saved 25 users’ lives. (Whenever a doctor answers a question via the service, a pop-up box asks the patient whether the answer helped him, made him feel good, or saved his life. The number of “lives saved” by a given doctor indicates the number of people who checked that box. By this curious logic, HealthTap figures that its doctors have collectively saved 16,336 lives.)

On the basis of all this information, if you were in search of a family-medicine physician in Northern California, you might well seek out Duchicela, who practices in the Bay Area and teaches doctors-in-training at a Stanford-affiliated residency program. Especially in the tech-obsessed South Bay, Duchicela says, if a doctor doesn’t have an online presence, “patients think, Are you still using leeches?”

In keeping with his enthusiasm for new doctoring platforms, he was among the first to jump on board when Prime launched. When he can spare the time, he picks up a shift, during which he generally hears from a handful of patients. He can log in from anywhere, has to do almost none of the bureaucratic paperwork that burns physicians out, and gets to meet and help interesting people in that predictable, finite, and instantly gratifying way that typifies Internet interactions.

I wanted to experience a HealthTap consultation from a patient’s perspective, so I waited for something to happen to me. The editor of this magazine suggested I get myself punched in the face. I turned that over in my mind. Luckily, my throat started to feel scratchy. The next morning, it was legitimately sore. Jackpot.