Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) cyclic vomiting syndrome ?
    ### Response:
    Cyclic vomiting syndrome is a disorder that causes recurrent episodes of nausea, vomiting, and tiredness (lethargy). This condition is diagnosed most often in young children, but it can affect people of any age.  The episodes of nausea, vomiting, and lethargy last anywhere from an hour to 10 days.
    