You're right, BS, this product does contain both. If all you have are simple cold-like symptoms, what I think I'd do is try a decongestant (without the antihistimine) during the day and an antihistimine (without the decongestant) at night before bed. This would help you function better at both times and wouldn't be overmedicating yourself. Typically, most doctors will, if it's just a simple cold, recommend that you not take medicine for symptoms you're not having. And, would recommend that you try to eliminate some of the side effects - like your drowsiness.
(Please note that I'm not trying to push products here - these are just 2 examples - there are many other name brands that are just as worthy.) But, an example of the above would be to take Sudafed during the day and an Actifed before bed.
If you're having any other symptoms, if what you have is not a simple cold, if you have any reservations about anything, if you have any other concerns, if your symptoms increase, whatever - please, please, please call your doctor. They are there to help you, and they may have a medication that will help you get over whatever you have more quickly and more easily. Remember that I am not a doctor (nor play one on tv), so my suggestions are only suggestions.