You do not know what is ailing your snake. The only safe and proper way to treat a potential infection is to see a trained veterinarian. Self medicating is risky and may not help this animal at all.
That being said...
You describe wheezing but describe no other symptoms. Is there mucus on the mouth of the snake, bubbles coming from the nose, excessive yawning, stretching vertically and constantly?
What other symptoms besides wheezing are you observing? Is this wheezing only when you attempt to handle or feed the snake? How does it sound when not in a condition of stress? What other observable behavior that is out of the ordinary are you seeing? Do you see anything mucous-y or snot bubble like coming from your snake? You need to do some detective work before you can say one way or the other if this is defensive posturing or illness.