SELECT with ' in search term

If the variable $segment has an ' in it the $query won't work because of
having 3 ' 's.

Should I be using:

$segment = mysql_real_escape_string($segment);

before querying the database?

$query="SELECT `reference` FROM `bible_concordance_words` WHERE `word` =
'$segment' LIMIT 1";

Please note:  $segment wasn't submitted through a form.

Thanks.

Ron