allergic reagin

例句：

1. 1. The allergic reaction caused by the pollen was severe.
   花粉引起的过敏反应很严重。
2. 2. The doctor prescribed an allergy medication for her.
   医生给她开了一种过敏药。
3. 3. Allergies can be triggered by a variety of factors, including environmental allergies and food allergies.
   过敏反应可以由多种因素触发，包括环境过敏和食物过敏。