A biphasic reaction consists of:
(1) an acute allergic reaction following delivery of the allergen
(2) complete resolution of the symptoms following therapy
(3) onset of late-phase symptoms, often within 8 hours
Parameters:
(1) gender
(2) age
(3) number of doses of epinephrine given
Parameter
|
Finding
|
Points
|
gender
|
male
|
0
|
|
female
|
1
|
age
|
< 18 years of age
|
0
|
|
>= 18 years of age
|
1
|
doses of epinephrine given
|
0 or 1
|
0
|
|
>= 2
|
1
|
total number of risk factors =
= SUM(points for all 3 parameters)
Interpretation:
• minimum number of risk factors: 0
• maximum number of risk factors: 3
• The higher the number of risk factors the greater the risk of a biphasic reaction.
In general a biphasic reaction that occurs following allergen immunotherapy were mild and did not require an additional dose of epinephrine.
An additional risk factor could be a history of a biphasic reaction in the past.