Low blood pressure. The definition of too low a blood pressure is 1. Non-hypertensive (<120/80) and 2. Symptomatic. In other words, blood pressure is not too low unless associated with symptoms such as dizziness, fatigue etc. On the reverse, ideal blood pressure is the lowest blood pressure tolerated. I have many patients with blood pressures in the 90s who are feeling absolutely great!
Variable. Blood pressure is too low when it causes symptoms. The rapidity of decline of BP is more important than the absolute number. Many healthy people feel fine with a pressure of 90/60. Some people may pass out if they go from 200/100 to 140/60 on standing. The lower the bp, the healthier if one is otherwise feeling okay.
Symptomatic. It's too low if you have symptoms for example, there are people that walk around with blood pressure of 90/50 without any problems. There are others who are dizzy, wobbly and feel horrendous. Some of these general guidelines go out the window dealing with really sick people, intensive care etc. Different set of rules in that case. Read more...