I usually do my best to wait it out or sleep it off. Can't let your body get used to being babied. If it persists, go see a doctor. I've seen people get addicted to Neurofen [contains a mild opiate], so I'm a bit wary about popping pills to alleviate ailments.
I do drink Lemsip when I've got a particularly nasty cold, though. Probably not a good thing. But it's delicious.
Oh, and decongestant in the same situation. But that stuff usually knocks me the hell out or gets me slightly high. Again, I should probably man up.