Hi all, Just wondering if anyone has info about POTS diagnosis (or similar conditions)? I saw a cardiologist about a year ago and had an ECG, 24 hour monitor and stress test - all were normal. I have had extreme dizziness / imbalance / feeling like I will faint when walking / standing / upright, this varies in severity from slightly annoying to almost impossible to deal with. Also had extremely bad headaches and tinnitus. When I measured my blood pressure and pulse lying down, then at 2, 5 and 10 minutes, my blood pressure only changed slightly but pulse went from 75 (lying down) 115 (on standing) 110 (2 minutes) 100 (5 minutes) 100 (10 minutes) Am I correct in thinking that for a 'formal' diagnosis of POTS, the pulse rate has to stay more than 30 above resting rate for at least 10 minutes? Or does it just need to increase by 30 at some point within the 10 minutes? Secondly, does anyone know how to encourage a GP (in the UK) to send me for a tilt table test? I have had so many tests and this is a symptom that has probably the biggest effect on my daily life, and i don't know how to resolve it! Thanks for any info / suggestions.