Before you investigate sinusitis, the first thing you need to look at is the possibility you have laryngeal reflux - this is a HUGE cause of chronic cough, throat clearing, sinusitis-like symptoms and asthma-like symptoms. Many people who have been treated unsuccessfully for years for asthma-like and sinusitis-like symptoms discover they have been taking the wrong drugs all along.
Laryngeal reflux is known shorthand as "LPR". It is also called larygealpharygeal reflux. In short, it is the presence of stomach acid in your throat - and it's not supposed to be there. This acid, with a very very low pH of 2 is very irritating to your throat and the tissues there, in particular, the larynx, which has no natural protection against acid. People with LPR are compelled to clear the acid from the larynx by coughing - all the time. This explains why it's a dry cough - you are not hacking phlegm from your lungs, you are just clearing a little bit of acid/mucous off your larynx and even the smallest amount can be irritating.
The forum for LPR is the GERD message board. GERD is the better known form of acid reflux which causes heartburn. LPR doesn't have it's own message board, but since it's a form of acid reflux, we post on the GERD board. There are lots of threads and discussion of LPR. In fact, over 50% of the posts are on LPR, because it's a more chronic condition than GERD. GERD sufferers usually have an easier time getting their symptoms under control, but LPR patients require more agressive pharmaceutical therapy - perhaps because the acid rises higher - and noone knows why.
The good news is that it is usually treatable with 2 doses of a Proton-Pump Inhibitor a day. A Proton Pump Inhibitor (known as a PPI) is a drug that suppresses most (but not all) acid production in the stomach (and possibly the larynx- which is now thought to also mistakenly produce acid sometimes). By lowering the amoung of acid in the stomach, theory has it that that much less acid is able to rise up out of the stomach through the esophogous and into the throat. Though doctors aren't sure exactly what causes LPR (faulty upper or lower esophageal spinchter muscles or faulty larynx), the medicine is usually quite effective, but only if taken 2x per day. The critical difference in treating LPR vs GERD is that LPR patients must take 2 PPIs per day and GERD patients only need 1 PPI per day. You will see this difference over and over again on the GERD board.
PPIs are sold by prescription as Nexium, Aciphex, Prevacid and Protonix. I've listed these the general orde of effectiveness for LPR, from most effective - least effective based on participation on this board for over a year, and my personal experience dealing with LPR.
In addition, there is 1 PPI sold OTC called Prilosec that I dont' personally recommend, from experience and through the community. Though it's OTC and a little cheaper, it doesn't really appear to be effective for LPR patients - it's more effective for GERD patients. It is also the 1st PPI to be put on the market, and as such, the 1st to lose it's patent and go OTC. The other drugs I listed by prescription are newer, and generally, better for LPR patients. In particulary, Nexium and Aciphex have a lot of fans on the GERD message board.
Exercise can increase symptoms of LPR and GERD. Any kind of bouncing motion can cause acid to rise up through the esophogous and into the throat (in particular, jogging and aggressive aerobics). Secondly, any kind of stomach crunches also squeeze acid from the stomach into the esophogous, putting it on it's path up to the throat.
Most diagnosis is done indirectly. You ask your doctor for a 2 week supply of Nexium or Aciphex sample and take 2x a day (together, preferably). If you respond to the drug, you have acid reflux. If you want to check more directly, you can visit an ENT and ask for a "scope". This is done in-office, involves inhaling a numbing spray in your nose and the doc inserts a thin metal wire with a camera at the end of it up your nose and down your throat. The camera projects onto a monitor adn the doctor looks for the presence of a red and swollen larynx - evidence of acid reflux in the throat.
Many doctors still do not know that LPR needs to be treated more aggressively (2x per day) than GERD. It is often up to you to educate them. There are many places where this is documented. Ususally, docs at university teaching hospitals are are more familiar with LPR. The local-yocals often have no clue.
Once you begin PPI treatment, you may experience tremendous relief on the 1st day, a common phenomenon amongst LPR sufferers, who have been undiagnosed for months or years. For instance, I was on 1 PPI a day for 6 months with no relief at all. Then I found a doctor who put me on 2 PPIs a day and I was "back to normal" 30 minutes after taking the double dose.
Sometimes you may need to experiment in finding the right medication. Give each one a week until you find the right one.
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