Why can you wake up, and immediate become allergic to something in your environment, but not have it affect you while you’re asleep?

Question

Why can you wake up, and immediate become allergic to something in your environment, but not have it affect you while you’re asleep?

In: Biology

Answer 1

The sense of smell is [highly dulled](https://www.sciencedaily.com/releases/2004/05/040518075747.htm#:~:text=Scents%20Will%20Not%20Rouse%20Us%20From%20Slumber%2C%20Says%20New%20Brown%20University%20Study,-Date%3A%20May%2018&text=Summary%3A,a%20new%20Brown%20University%20study.) during sleep. It’s one of the last senses to fully return when you awaken.

We also take fewer and shallower breaths when we sleep, and consume less oxygen. My resting heart rate while sitting is about 58 BPM on most days. While sleeping, it’s usually 42-43 BPM.

I cannot confirm if these are directly related to the histamine allergic response in the nasal passages. Just an idea.