Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the symptoms of Cyclic Vomiting Syndrome ?
    ### Response:
    The main symptoms of cyclic vomiting syndrome are severe nausea and sudden vomiting lasting hours to days. A person may also experience one or more of the following symptoms:
                
- retching, or making an attempt to vomit  - heaving or gagging  - lack of appetite  - abdominal pain  - diarrhea  - fever  - dizziness  - headache  - sensitivity to light

    