osmoprep reaction??

Has anyone ever had a colonoscopy using Osmoprep and had a long-lasting (7+ days) sinusitis drainage reaction?  No infection; just clear fluid or muscus but continual and heavy-duty for over 7 days now.  It started about 6 hours after the colonoscopy.  No gas or cramping after the procedure (and thankfully no problems found) but a huge fluid dump about 2 hours afterwards, and then the sinus drainage started up about 4 hours later and has kept on since.  The only things I've found that have relieved it a bit are a decongestant called Ornex and an antihistamine (Mucinex doesn't work because nothing in my lungs to cough out), but I don't want to take much of either as basically what they do is thicken the drainage and make it harder to blow my nose.  My doctor seems never to have heard of this side effect but I think not a bug I picked up at the hospital as it hit too quickly after the colonoscopy.  Of course I'm concerned about dehydration--first from the bowel, and now the sinuses.  Thanks for any advise.