Mucinex in fertile window?

So this is our last month trying before the OBGYN appointment.... I have a terrible cold brewing and my hubby had oral surgery this week, so we are SUPER in the mood for my fertile window...... But we have to try since it's, an important month. It occurred to me maybe I should try Mucinex to kill two birds with one stone, anyone have experience with this? Should I just get the plain one with only the G word I can't spell? ????