An online doctor is generally a health professional that writes medical articles or directly answers people's questions by email or chat. When not writing for a personal website, doctors are usually paid a good sum for each article they submit to medical websites. Directly answering questions can also be a paid job, but sometimes a doctor does this for free. Sometimes, symptom checkers are also referred to as online doctors. Symptom checkers are web programs that allow a user to input symptoms, then gives the user a list of conditions that might be causing those symptoms.
In general, doctors that write medical articles for popular medical websites are freelance writers, in addition to being health professionals. The doctor typically chooses a topic from a list, then writes and submits it under his or her own name and credentials. An online doctor is often heavily screened to ensure that his or her certifications are real and that he or she is qualified to write on the chosen topics. Some doctors write while still practicing medicine, while others write full-time.
A lot of websites are now offering to let users talk to real doctors via chat or email. Often, these services are completely free for the user but the doctor might take days or even weeks to answer — this service is not meant to be used in emergencies. Many people use this service in order to get a second opinion on a minor ailment that was either dismissed or could not be fixed by a previous doctor. Other people use it to get advice on sexual or mental health issues, among other problems.
While there are free services, immediate help is often available through a paid online doctor. Some websites demand a flat fee to speak to an online doctor. Other websites allow users to bid money, then a doctor can choose to accept the bid and begin chatting to the user. Often, the bid is submitted along with the question, and the doctor emails a response soon after acceptance, with the length and detail of the response determined by how much the user bid. These doctors are not recommended for use in emergencies either.
Another type of online doctor is simply a web program that tries to diagnose a person based on his or her symptoms. Like an actual online doctor, it is possible that these programs will misdiagnose a problem. The best method of diagnosing and treating an ailment is to see a doctor in-person.