(environmental factors) what can hay fever cause

### Hay fever can cause watery eyes, runny nose, lethargy, and flu-like symptoms.

## Step1: Identify the symptoms of hay fever### Hay fever, also known as allergic rhinitis, is an allergic reaction to certain types of pollen, dust, or pet dander. It is characterized by a number of symptoms that affect the upper respiratory tract.## Step2: Recognize the common symptoms of hay fever### The most common symptoms of hay fever include watery eyes, a runny nose, and lethargy. These symptoms are caused by the body's immune response to the allergen, which leads to inflammation and irritation in the nose and eyes.## Step3: Acknowledge additional symptoms of hay fever### In addition to the common symptoms, hay fever can also cause flu-like symptoms. These may include fatigue, low-grade fever, and sore throat. These symptoms occur as the body tries to fight off the perceived threat posed by the allergen.