What Causes A Sense Of Blockage In Throat And Ear?

I have suffered from Acid Reflux, year round allergies and Chronic Rhinosinusitus for 6 years now. My symptoms seem to come and go. However, when I have a flare up my left ear becomes plugged, and I feel like I have something stuck in the left side of my throat that I just cant clear out. I have heard it could be swelling of my left eustachian tube or mucous draining. What could this be? Are there any ways that I can relieve this feeling from my throat?

Thank yoU!