Cache stampede when multiple requests hit an expired cache? How to prevent it

Hey everyone, I've run into a weird issue with our caching. Basically, when an item in the cache expires, a bunch of requests for that same item hit us all at once. This means all those requests go straight to the database at the same time, and that's definitely not good. Does anyone have any good ways to handle this 'cache stampede' thing? I'd love to hear what you guys have done.