Visual Fatigue 
Major causes:
- Long time use of eyes (reading or electronic products using)
- Blink less
 
Signs and Symptoms:
- Headache
- Tearing or dry eyes
- Blurred or double vision
- Sore tried, burning, or itching eyes
 
Complications:
- Dizziness or headache
- Vomiting
- Neck and shoulder pain
 
 
Prevention:
- Have good rest
- Remember to blink