Antibiotics don't work on colds..colds are caused by a rhinovirus (keyword = VIRUS). Antiobiotics work on bacterial infections only, not viral infections.

If you have a respiratory infection that followed a cold, that is often a bacteria and treatable with antibiotics.

When I started the airline thing I got a lot of colds, but a little research narrowed the causes down:

Deydration: Weakens the immune system. Airplanes are dry and it's annoying to have to open the door in flight so I used to not drink much water. Now I pound all kinds of water in the last hour of each flight...and **** like a racehorse after the pax deplane.

Excess booze on overnights: Dehydrates you and weakens the immune system.

Poor Diet: Weakens the immune system.

Diseased PAX: This is where the sickness comes from. I avoid pax like the plague (no pun intended). I don't touch anything they touch, and I wash my hands with soap every leg. If I have to cross seatbelts (or deadhead) I wash my hands immediately after.

Cockpit: During the winter diseased pilots can be a problem...wipe down the controls with alcohol wipes (it will take 4-5 to do it right).

Meds: I always carry Airborne and Cold-eeze (zinc)...if I feel a throat thing coming on I start popping that stuff. It does work if you start early and get as much rest as possible (go to bed, not the bar if you're feeling down).

I rarely get colds anymore, maybe once a year.