Nasal provocation
a) Patient will challenge by the allergen solvent first as solvent
control. A special nasal spray device will be used for nasal provocation
tests. Two doses will be sprayed on each side of the nasal cavity, with
an average of 0.05 mL each dose, one in the direction of the common
nasal meatus, and the other in the direction of the middle meatus.
Patient should to take a deep breath before spraying, then hold breath
during the spraying procedure, take deep breath afterwards. Then we will
evaluate the symptom and nasal examination within 10 minutes in
chronological order. We found the solvent provocation did not cause more
than 50% of the symptoms increased or 30% nasal flow decreased. (Table
E2). So the allergen solvent challenge is negative, we can do allergen
solution provocation.
b) The nasal allergen provocation was performed at least 10 mins after
solvent control. Same as solvent provocation, two doses spray will be
given on each side of patient’s nasal cavity, with an average of 0.05 mL
each dose, one in the direction of the common nasal meatus, and the
other in the direction of the middle meatus. Patient should to take a
deep breath before spraying, then hold breath during the spraying
procedure, take deep breath afterwards. Then we will evaluate the
symptom and nasal examination within 10 minutes in chronological order.
The provocation is defined as positive when subjective measures is
clearly positive or objective measures is clearly positive or both
subjective and objective measures are moderately positive, based on the
EAACI Position paper on the standardization of nasal allergen
challenges. After allergen challenge, the symptom score increased by
more than 50% and the nasal airflow decreased by more than 30%
compared with baseline and solvent control. The nasal provocation test
was successful (Table E2).