What Causes Constant Need To Clear The Throat During Nights?

I m 60, male, and in very good physical health. I have no history of any chronic illness other than seasonal allergies and asthma, both of which I get occasionally in the spring. I am physically fit and am an active amateur athlete and recreational runner. The only prescription medication I take is via an inhaler that I use occasionally for my asthma. I can generally manage my allergies with over the counter allergy medication. This spring, I have had mild allergies and asthma on occasion - but I have also been having the frequent sensation of needing to clear my throat, especially at night. My inhaler does not address this. I m at a loss for what this could suggest or mean. Could this be an allergy? Thank you.