I don't know the exact cause of my anosmia. There are 4 contributing factors that came into play at the same time. A CABG (Coronary Artery Bypass Graft) operation (one trigger), diabetes type II, loss of Xanax after 20 years (the other trigger), and chemical sensitivity. My sense of smell is waning, but not gone completely. It really affects what the tongue does with taste, which is also gone. Bitter is about gone. Salt is really pronounced. The Japanese have identified a fifth sense for the tongue. I can't remember what it is. Sometimes I can smell something smoky like burning electronics when there is none. Cigarette second hand smoke really smells very obnoxious (I don't smoke - I quit 20 yrs ago) and repulsive. It didn't bother me, but now I can't be in the same room with it.