Shortness of breathe can also be caused by inflamed vocal chords. The vocal chords sit at the top of your airway and can become inflamed from acid reflux, which you may not even know you have (silent reflux). The steroids in the premeds for chemo trigger stomach acid, and can cause or make this problem worse. I’ve had a real problem with this since starting chemo. and it’s also made worse by an over-production of bile in your stomach. If it feels like you can’t get air IN, then its likely a vocal chord problem. Unfortunately, theres no real cure other than controlling the stomach acid. I can’t take a lot of the acid reducer medications, but find sucking on Gaviscon helps. There are also breathing exercises that help the chords relax.
If my legs feel tired, its probably due to low blood counts, but if I feel like I can’t get a breathe, then its in my throat. For me this became a real quality of life issue. I can do stuff if I’m tired, but tired AND can’t breathe is a double-whammy.
Anyway, if the allergy meds don’t work, try some antacids.