atrial fibrillation
"I have had no major adverse effects from taking Xarelto.  However, it seems that since starting this, the back of my lower neck itches all the time.  I have scrubbed my neck, I have no rash or appearance of anything unusual, just the itch. Wonder if this medicine could cause this.  I believe I ran across an article of someone complaining of the same condition but I don't know where I saw it."