REGEX-Escape for: http://sildenafil02.us.com/ - sildenafil citrate

Your Input:
Result, the escaped string:
http\:\/\/sildenafil02\.us\.com\/ \- sildenafil citrate

What must the escaping look like for:
http://sildenafil02.us.com/ - sildenafil citrate

The excaped text for use in a regex is:
http\:\/\/sildenafil02\.us\.com\/ \- sildenafil citrate