Displaying untrusted HTML using PHP

I have a read a number of excellent questions and answers today about dealing with user input. I am now using htmlspecialchars() to display user data in the create/edit forms (but accepting the raw input via prepared PDO statements into my database).

The main question I know have is, what do you do when you are allowing the user to submit HTML which will then be displayed to the public. Obviously htmlspecialchars() is no longer suitable as it just encodes the tags and renders the conten开发者_JAVA技巧t useless for purpose.

My application is currently accepting HTML from an admin for product descriptions. This would allow a malicious admin to inject potentially unsafe data into public facing pages.

How do people cope with this?

HTML Purifier.