Doctors receiving sexual advances from patients through social networking sites such as Facebook or Bebo have been advised not to respond to them in any way.
There have been several reported cases where patients have attempted to proposition doctors by sending them a private message via a networking site, according to The Medical Defence Union (MDU).
Users of social networking sites can have safety profiles on their account, which means only people who are their "friends" can access their home page.
The MDU helped a GP to stop a patient's advances but also told her how to use the security and privacy settings. Dr Emma Cuzner, MDU medicolegal adviser, has written about the issue in the latest MDU Journal.
She said: "The pitfalls posed to doctors using social networking sites by inadvertently breaching confidentiality or posting unprofessional content, such as photos, have been well documented.
"But doctors may be less prepared for patients using sites like Facebook to ask them out on a date. Doctors could face a General Medical Council investigation if they are accused of overstepping the boundary.
"They have a duty to maintain the public trust in the profession at all times, in their professional and private lives and not only when at their place of work."