Protonmail - a free secure email
Sending sensitive information back and forth to someone over regular email is not a good idea. Email has no encryption so it is easy for hackers or prying eyes to see the complete contents of an email message. I believe this is one of the reasons the medical industry shies away from using email.
One solution, one that we use at slscart, is to use proton mail. It works with desktop, android, and iOS. Email is double encrypted from the browser to/from the protonmail server - even protonmail cannot read emails!
Sign up for a free protonmail account