Why don't more cold meds include an expectorant? it seems like cough suppressants would just prolong things by keeping mucus inside.

You are right: That is why it is best not to use most otc cold and cough remedies, especially those that have every ingredient that can be put onto it.

The best expectorant: ....Is water. It works better than anything you can buy with regard to loosening and helping you clear mucus. Over the counter cold medicines have been shown, in many many studies, to help minimally if at all. Save your money. Sometimes, despite what medicine commercials would have you believe, medicine is not the best answer.