Spring is in the air and everyone is sneezing. So should you practice? The general rule for Ashtanga practitioners is to practice at home if you are sick (all those tissues are just gross plus you don't want to get anyone else sick if it is more than allergies) and to rest if you have a fever.
The use of a neti pot is recommended to lessen symptoms and here is a list of foods that might help. A neti pot tutorial below: