Hello and welcome to HCM. Thank you for your query. The diagnosis appears to be pyrexia of unknown origin(PUO) currently. As the cause has not been found. I would also advise a blood culture, which would greatly help in guiding the doctor towards treatment. I can understand it is frustrating when we cannot reach a diagnosis, this is because children present in a totally different manner and can not even express themselves the way adults can. Please be patient and request your doctor to conduct a few more elaborate investigations. Has a routine blood investigation been done? If yes, what were the reports? You could write back to me with the results of the blood test, as this can also help in assessing the condition, to see if there is an infection, hypersensitivity reaction, etc. Does your son have any other symptoms like loose stool, change in color or consistency of stool, cough, congestion, etc. In the meantime, please continue with the advised medication. I hope I have succeeded in providing the information you were looking for. Please feel free to write back to me for any further clarifications. I would gladly help you. Best wishes.