Sinus infection woes

Do any of you Frenchies out there know the name of a French decongestant, similar to the American Mucinex or guafenesin-based over-the-counter stuff?  I've been sick all week and I think I've got a serious sinus infection coming on.  A few months ago when I had a cold, I went to the pharmacy and explained my sinus pressure etc., and they just gave me this liquid to put in steaming water, which is about as effective as inhaling the vapors of a strong mint tea.

Who knew walking through the aisles of CVS and Walgreens was such a luxury?

Hopefully I can pick something up tomorrow before everything shuts down for the weekend, so if you have any tips, send 'em my way ASAP (glynnish > gmail).  Merci.