I went to get Mylanta for Mason at CVS. I got all the way to the checkout and waited in line for 15 minutes and then I flipped the bottle over and saw the date- It expired in 2009 so I had to go back and start all over again. It's annoying and since he was having screaming fits with his stomach I definitely wanted some fresh stuff
Generally though expired meds are good for up to 2 years past their date.