What Relieves The Pain In The Chest During Pregnancy?

I am pregnant with my third child and am experiencing a flare-up of my lupus (and R.A., Scleroderma, etc.). I have had chest pain on and off for 6 years and Echo, EKGs, and Chest X-Rays show nothing. The pain increases during pregnancy and also seems to increase during high allergy times. My Rheumatologist thinks it may be costocondritis and recommended Prednisone for 12 days since I cannot take NSAIDs. The Prednisone is not helping and the pain is so severe that I can t lay down at night (or bend over without wincing in pain). Tyllenol isn t helping either. Though the doctors always attribute it to my diagnosis of MCTD, I think it s often triggered by allergies (since the second I walk outdoors the pain increases significantly). I stopped my Nasonex and Claritan due to the pregnancy, which both seemed to be helping with the chest pain. Any thoughts? Any ideas for relief?