No. I would consult with your ophthalmologist prior to using a medication for something other than its prescribed use. Also, prophylactic use of antibiotics can contribute to antibiotic resistance.
Pink eye. The pink eye is likely viral so the zymar will not prevent you from developing it. It will not hurt anything though.
Get seen. Zymar is an antibiotic active against bacteria. "pink eye" classically describes a viral infection, for which zymar is not indicated. An eye exam can determine if it is viral, bacterial, or even something else.
No. Because pink eye is usually caused by a virus antibiotics do not help with the treatment or preventing the disease. The best way to prevent contact is practice good hand washing.
No. If you have been exsposed to someone with an eye infection, the antibiotic drop will not necessarily prevent you from getting an infection as many eye infections are due to a virus rather than a bacteria. You should cosult with the doctor who will be doing the lasik procedure. You may was to postpone the procedure for 10-14 days to be certain that an infection will not develop.
Preop antibiotic. It is our standard treatment to use preoperative antibiotics prior to lasik so I would use the zymar. In regards to using it due to exposure to pink eye, it does not make much difference since most pink eye is viral in nature and not covered by zymar.