Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Gallstones ?
    ### Response:
    People who think they have had a gallbladder attack should notify their health care provider. Although these attacks usually resolve as gallstones move, complications can develop if the bile ducts remain blocked.
                
People with any of the following symptoms during or after a gallbladder attack should see a health care provider immediately:

    