I believe my 82-year old mother is coming down with a cold. My husband has had one for a few days, and since she lives with us it just makes sense that's what it is. She takes Metformin, Levothyroxin, simvastatin, Namenda, and Aricept. Are there any cold medicines that I can give her for her symptoms, and are there any warning signs I can watch for that her cold is developing into something worse (since she can't express her symptoms and I have to watch and listen)?

If it is a viral illness then all you can do is symptom suppression. Any Over the Counter remedy can do this. Might be easy to manage your Mother if you do this. Maybe one that will just knock her out like Nyquil or the Generic equivalent. A cold, if I recall correctly, will last about a week. Anything more serious will last longer. How often are her medical appointments? Is there a way to get her into a doctor quickly. They might have good guidelines on how to asses her condition without her input.

Good luck.