Brief Answer:
it is not a likely reaction since this med decreases the body's immune reac

Detailed Answer:
HI, thanks for using healthcare magic

Budesonide is a steroid which would suppress the body's immune response or suppress an allergic reaction. It is not likely that you are allergic to this since steroids reduce allergic reactions.

It is possible to experience side effects of the budesonide but not likely an allergic reaction.
All medications have possible side effects.

The nasal congestion and wheezing can occur as part of the whole body's allergic or inflammatory response to another allergen (dust, pollen, animal dander, particular food/drink) or can occur with infections such as cough/cold.

If you are wheezing, you should use your reliever inhaler eg ventolin and using a decongestant would help with the nasal congestion eg zyrtec D, allegra D, benadryl D, claritine D.
The anti histamine on its own (zyrtec), may not help.

I hope this helps, feel free to ask any other questions

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