Hi Jennifer, I posted this in another thread but it's advice that might help you too:

Ok... this should work: I had it soooo bad that not only was my nose blocked but I had sneezing fits/itching face/itchy eyes/itchy inside the ears... the final straw came when I would "wet" myself every time I sneezed which started to occur in my 2nd trimester. I spoke to my midwife and said that i needed a solution to this... she also said that it was caused by progesterone...I asked her were any antihistamines safe... she consulted this big thick book and gave me 2 brands: Avil and Polaramine. They are both apparently perfectly safe for pregnant women. They do make you drowsy but she said if you take one before bed it might actually help you sleep. I take Polaramine and it's worked... I feel 98% better and i suspect that when my symptoms return it's only because the tablet has worn off (they only last for 6 hours). Also, the pharmacist saw that I was pregnant and agreed that these 2 medications were safe. Better still they are cheap. Polaramine costs $10 which isn't too bad. You also don't need a prescription but the phamacist might like to hear that you've spoken to your midwife/OB about it. Good Luck!