Filtering User Input

Hi Experts,

I have a textarea that the user needs to provide comments for a varchar(4000) MySQL field.

Using PHP, how can I filter(or better - escape) malicious or even naive input like a semicolon in a sentence.

For my particular scenario I cannot use any binding (at least I don't think I can), because I am updating up to 50 records with the same comment.

Actually, I know I can bind within my loop, but that would mean hitting the database up to 50 times