I can't seem to get a straight answer on this. Some say take Guaifenesin, it will thin out the phlegm. Others say no, Guaifenesin will loosen the phlegm and make the drip worse. Some say take an antihistamine to dry up the phlegm and stop the dripping, others say no, it will make the phlegm thicker and more noticeable. Can someone help me out here? Thanks.

Everyone is different. For me, an antihistamine helps. I'd say try it and see what happens...you'll know in a couple of days. If it doesn't help, try something else.

I found antihistamines plugged me up but it did help with the drip. I now have nasonex - a nasal spray which works really well. Mind Ive only been taking it a week though!

IF the PND is caused by allergies than an antihistimine will help by reducing sinus irritation and mucus production. But if it is caused by a cold or infection, you want to let it drain, not dry it up.

Guaifenesin will thin it out, and sometimes, yes will make the PND worse as the stuff finally drains out of you. But after it is done draining, it will be better.

So in other words, sneezy diva, if you're drip is the result of a temporary cause - like a cold - you want to just keep draining it out because the flow will eventually stop on its own. But if the flow will never stop on its own, because the cause is chronic, you have to keep it dried up. Makes sense.

I don't have a cold. But the infection issue seems trickier to nail down. I have no sinus pain or pressure, no discolored discharge, no nasal congestion. I took a course of antibiotics as well. But now some have told me that antibiotics may fail to clear an infection. Or that also it could be chronic sinusitus, which is not caused by bacteria. How can I know for sure if I have an infection, whether it be bacterial, viral, or otherwise? What defines chronic sinusitus?

I suppose also I should get tested for allergies. How reliable are these tests?

Sorry if I'm peppering you guys with a million questions, I'm just eager to get to the bottom of this. Thanks again.

I've had Sinusitus for many years. My alergist has suggested I get "NeilMed", to irrigate my nasal passages. Its at most Pharmacy's. since using this twice a day. my sinuses are staying free of lots of mucas. I feel like a human again.