[mysterio]

Probably if you buy more than one box at a time. I used to use Contac as an allergy medicine a few years ago. They started giving me the hairy eyeball when I bought more than on box at a time, so I said screw it and stopped taking them.

[Quilla]

I've read that clerks in our local convenience stores who sell more than one bottle of some cold medicines are subject to arrest.

[Waterleak]

You sure it wasn't stinkeye or the omnipotent evil-eye?