Major sinus issues! Help!

I am 20 weeks pregnant and the main issue I've had is sinus problems. My nasal passages are completely block at night and I have extreme difficulty sleeping. I normal take Claritin-D, but since pregnant this is something I can't take😒. I've been using Benadryl, a humidifier, taking steamy showers, and a Neti-pot but nothing gives me relief! I've already gone through 20 boxes of tissues since February 2015. Any suggestions, because I really need some sleep!