Worsening orthostatic hypotension
Hello - I am a 33 yo female that has always had low BP (~90/70) and dizziness upon standing. Over the past year, I had about five fainting spells, usually correlated with migraine headaches. However, beginning about a month ago, I began to experience extreme dizziness upon standing every time I stood and would faint every time I stood. After a few days and few minor head injuries, I figured out just to sit down when I felt faint, and I've only fainted twice since, but every day now I cannot stand up without feeling dizzy and faint and any type of movement leads to a dizzy spell for which I have to sit down. My cardiologist told me to push fluids (I now consume about 4 L of electrolyte water a day) and increase salt intake. This has really done nothing, and each time I see a doctor and they check my BP, it has continued to fall. My new sitting BP is about 60/30. My pulse however always seems to be very high (110) and always feels like its constantly racing.
I have had adrenal testing (I show some signs of adrenal insufficiency, but the tests are not conclusive enough to warrant a diagnosis of this). My thyroid panel (TSH, FT4, T3, FT3) results are all in the low normal ranges. Electrolyte balance is normal, and EKG's are normal.
I am extremely fatigued, have severe muscle pain, insomnia, and still experience migraines and tension headaches, although these have decreased since I was able to get Botox injections for a condition known as chronic migraine (9 or more migraines per month). I have been dx with fibromyalgia in 2004 and also depression. I take medications to manage these conditions, and there is some incidence of side effects of hypotension from certain meds that I take. I have experimented in the past month with reducing the medications I can that potentially exacerbate this condition, but nothing seems to help.
I feel like my life is slipping away and I don't really know what to do or where to turn next. Since this came on very suddenly, I don't know if this indicates anything special or not. I would welcome ideas from others that have similar experiences and what diagnoses/tests/remedies have helped.