Does masturbation cure hangovers?

No. But trying to rehydrate yourself helps.

Not in the literal sense - hydration is important. But getting the blood moving helps your body process and remove a lot of the alcohol by-products that are making you feel bad. Besides it takes your mind off the misery!

Never heard of it

I don't think so. I can't usually even get hard even after a night of heavy drinking, let alone have a thought of masturbating. I think the best cure is to drink plenty of water!