Low Blood Pressure

Hi all, I had a abdominal hysterectomy nearly 1 year ago and afterwards experienced periods of dizziness and nausea. This mainly occured when I was away from home and in a busy place. Consequently I thought I was having some sort of panic attack, although, after visiting the doctor she did say that my blood pressure was slightly low. The symptoms eventually subsided and I forgot all about it. However, in the last couple of months the symptoms have returned. I went to the doctor after a couple of really unpleasant episodes and she said that when seated my blood pressure is fine but drops when I stand. She said that I am probably panicking when I feel the symptoms coming on and make it worse! The symptoms this time round are mainly feeling sick with a ‘fuzzy’ head and sometimes I feel like I’m speaking really quietly. Today I felt really bad and added a sachet of salt to a small bottle of water and felt much better after about half the bottle. Was this in my head or can a bottle of salty water really make a difference that quickly? I would love to hear from anyone with any other tips on raising blood pressure quickly and also if there is anyone who can shed any light on why this has happened now after a lifetime of normal blood pressure (I’m 40ish!). Many thanks