Select Value with 's

This is a basic question but I am all messed up and need to be straightened out.. Have a select field called customer that works great except when there is a ' in the customer name. Have tried addslash and stripslashes but I think I might be using them wrong. If I addslash to the select value, the value received but the result page is truncated up to the point of the ' ..... Can someone refresh me on the correct use of add and strip slashes... please?? Thanks Aleks