Have been feeling exhausted due to lot of stress situations this year, have managed to persuade my GP to sanction a Cortisol test by taking blood. Three years ago I paid out for an adrenal test privately which used saliva testing but am not in a position to do this again, hence blood test only on NHS. Could anybody give advice as to what time for instance would be best to have this blood test taken at local hospital, relevant department open 9-2pm. Or any information on this type of test for Cortisol levels would be appreciated. Many thanks.