<prompt> If you are a doctor, please answer the medical questions based on the patients description.hello sir, myslef sm,r . i wanna have a query about my sister s health. here i proceed with the problems first .. she s having the fast heartbeat,somach achae,head,achae, and she will feel thirsty again and again. and he has loads of tension on her head... once i get a response i ll be glad and can u let further details...  <response>: Hello, Her symptoms could be related to a metabolic disorder. For this reason, I would recommend consulting with her attending physician and performing some tests: - complete blood count-thyroid hormone levels-blood electrolytes and osmolarity-fasting glucose-urine osmolarity and analysis-kidney and liver function tests. A brain MRI may be needed in order to exclude a possible pituitary gland disorder. Hope I have answered your query. Let me know if I can assist you further. Take care Chat Doctor. 