Andi,
I've been to Rome and you are so lucky to be going there! The exhaust from the cars is not so great -- so what I do when travelling is...I hold a 3M Charcoal mask with me and when I'm in traffic I pop it on. Otherwise the car fumes can really make problems for you. I wear it anywhere if I think the odors are strong. My doctor recommends wearing a mask on the plane, but I find I cannot breathe with the thin air. A second choice is a silk scarf which isn't as thick. If you don't want to do that, you might just want to wear the mask in the restroom because of germs and the strong smell of cleaning fluids in there.
For years, I also use a personal air purifyer around my neck. The brand is Wein and you can get it on-line. I used to always get sick from flying and I don't any more. Maybe this has something to do with it.
My doctor makes me take an Epi-pen with me on plane -- because if you have any allergic reaction, and you are in the air, well, you want to be safe. And I carry an inhaler too which I use to before and during the trip. I don't know if you take inhaled steroids, but if you don't, it might be worth discussing with your doctor.
If you get an e-flow, that would be best, if you don't I can give you other suggetions about that.
I couldn't find any isopryl alcohol anywhere in England, so I would get a box of alcohol squares 70% in Target. They had Ethyl alcohol which left a residue on everything. I don't know about Rome. Next time I will bring my own bottle -- it may need a medical note too.
I took cold remedies with me (as someone mentioned) I couldn't find Airborne, Zicam, or Zinc lozenges, or Dristan spray anywhere. I take my nasal rinse and pre-mixed salt packets with me.
I always take a small supply of meds with me including prilosec, a probiotic, monistat cream...
The Auto Club has $100 money packets in foreign currency to get you started if you belong.
If I think of anything else...I'll be back.
Have a great time.