The combination Hexamine / Piperazine / Khellin is used to · Prevent recurrent infections of the urinary tract. · Prevent kidney stone formation. · Treat muscle spasm of the urinary tract. · To ease pain from a urinary tract infection.,, Do not take Hexamine / Piperazine / Khellin · If you’re allergic to the active substances or any other component of this medicine. · If you have kidney problems. · If you have severe liver problems. · If you are taking sulfonamide antibiotics. A valid prescription should be available upon delivery