One example is Lemonaid, a startup based in San Francisco that has three physicians, all of whom are licensed to practice in every state. Another is Denver-based CirrusMD, which is available in every state and provides patients with a "chat-first" approach. It claims that patients using its app can chat with a licensed doctor within one minute.

The number of doctors licensed in every state is still exceedingly small: only 14 in 2018, according to the Federation of State Medical Boards. But the number will only increase as telemedicine grows.

Getting medical licenses in multiple states can be time-consuming and cost tens of thousands of dollars.

There are ways to make the process easier, such as the Interstate Medical Licensure Compact, an agreement involving 24 states that provides physicians an expedited application process if they are already certified in one of the participating states.

Most of the states that are members of the IMLC are small. They are the ones that telemedicine doctors would be most likely to pass up if the application process was difficult. The only relatively large states that are members are Illinois and Michigan. Most large states –– California, Texas, New York, Florida, Ohio, Pennsylvania –– are not members.

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