Sinus Problems After a Swim

The same happens to me; I take the 24 hour claritin on the day that I swim and maybe the next, nasonex nose spray prior to swimming, showering BEFORE and after makes a difference since what usually causes the allergy is the byproduct of what chlorine breaks down off your skin.  My symptoms were getting so bad that I developed a wheeze and was taking puffs off an inhaler, but now that I have been in the pool more consistent the reaction has lessened.

So try showering before and see what happens if you don't want to take the medication.

I have had this problem and I started using a nose clip as goofy as they look.  Since doing this for about 2 months now, no need for antihistamines or other medications since doing that and no sinus pain or problems.  I did use it in the triathlon - not sure I needed it but had it with me so I did use it.  I know some people breath out of their nose when swimming but I am a mouth breather anyway when I swim so the nose clip did not interfere with that.

Hope you find a solution that works for you.

I got a sinus infection that lasted five months from a sensitivity I must have developed from the chlorine (at the time I was not swimming open water.) I was sneezing like crazy after swimming and then I just was plugged up constantly.

Like another poster, I started using a nose clip. Never got another infection. It takes maybe one or two swims to get used to the clip but once you are it's absolutely a non issue. 

I think if you're swimming a good number of laps, at least for me, it's hard to avoid a tiny bit of water in the nose w/ all those flip turns.

 I had they same problem right after I started swimming.  My wife got me the Neti pot and I used it after swimming for a couple of weeks and now I have no problems after swimming.