<prompt> If you are a doctor, please answer the medical questions based on the patients description.Dear Sir, I was very ordinary person with normal blood pressure, last days, I have very low blood pressure 50, with high pulse rate over 130, this happen when i stand up, I feel feel week dazy,I could not resist to stand and i go down to ground. All my blood analysis is OK.  <response>: Hello! Welcome and thank you for asking on Chat Doctor! I understand your concern and would explain that your symptoms seem to be related to orthostatic intolerance. There are different causes that may lead to this disorder. I recommend consulting with your attending physician and performing a Head Up tilt tests to rule inout this possible disorder. Further tests may be needed to establish the cause and the proper therapy. You should know that there are many treatment options pharmacological and non-pharmacological for this disorder. Meanwhile, I recommend taking plenty of fluids water, juices to avoid deny Chat Doctor. You should also try to avoid straining physical activity. Hope to have been helpful! Best wishes! 