Is there any color to the discharge from the nose or eyes, or is it clear?
Does he go outdoors?
Standing by to help...
Great, thanks for the info...
A cat at his age should be able to fight off a cold on his own, however, keep a watchful eye on him. Lots of cats will stop eating if they can't smell which is very dangerous. If he stops eating for more than 2 days, he risks developing a liver problem called hepatic lipodosis. This makes him feel so bad that he does not want to eat, and the only cure for it is, well eating, and most cases need force feeding. He will need to go to the vet for antibiotics immediately if he stops eating, has a green or yellow discharge from his nose or eyes, becomes lethargic or his condition worsens in any other way. Bring him into the bathroom when you shower so he can breath in the steam to help clear him up and make him feel a little better. You can also give him a ¼ tablet of Chlor Trimetron (can be purchased at a pharmacy in the cold section), to help him feel a bit better. Really the most important thing is to keep an eye on him for any of the things mentioned above.
Hope that helps!