Hi
@Justin30
I don't have an exact answer for you. But I do have a reference listing a recommended amount of potassium for patients with Orthostatic Intolerance (POTS or NMH) who are taking Florinef (fludrocortisone).
INFORMATION ON MEDICATIONS USED FOR TREATING NMH OR POTS
...
1. FLUDROCORTISONE
Brand name: Florinef
Type of drug: a mineralocorticoid steroid
Indication: NMH or POTS
Action: Florinef acts in the kidney to help the kidney retain sodium that would otherwise be lost in the urine, and it may also help blood vessels constrict more readily in response to epinephrine and norepinephrine. It helps the body avidly retain the salt you eat. It does so at the expense of losing potassium into the urine, so it is important to take in adequate amounts of potassium each day. We recommend potassium supplements when people start on Florinef, regardless of the serum potassium level, and especially if individuals remain on the drug for several months. A sustained release potassium preparation (containing 8-20 mEq) given once daily has been well tolerated by our patients.
(emphasis mine)
This section makes it sound like the serum level of potassium is not a very reliable measurement?
This extract is from page 14 of the following document:
http://www.dysautonomiainternational.org/pdf/RoweOIsummary.pdf
I'm also taking a prescription version of potassium along with Florinef. It's a time released version, and has 10 mEq potassium (which is about 750 mg).
http://www.rxlist.com/klor-con-drug.htm
I don't know whether POTS patients are advised to take extra potassium if they're not on Florinef.
I've attached a document on POTS that might help? Of course, some of these documents on POTS don't always apply to patients who have Orthostatic Intolerance in addition to ME or CFS. (or as a part of ME/CFS, depends on diagnostic criteria used)
Sorry, I don't remember details of this document and do not have time/energy to re-read it right now. But I hope it is helpful for you!