Pyridostigmine + Midodrine?

My mum has been struggling with severe low blood pressure, particularly sudden drops when standing that lead to fainting. She was initially prescribed fludrocortisone, but it didn’t help much and she didn’t tolerate it well. She’s since been switched to midodrine, which we’ve been increasing gradually—currently at 7.5mg three times a day. It is helping, but only slowly and inconsistently. She still experiences major fluctuations and episodes of fainting.

To complicate things, she often has supine hypertension—systolic readings over 200 mmHg while lying down. This usually resolves after standing for a minute or two, but then her BP crashes again.

I recently came across pyridostigmine as a potential treatment that can help raise blood pressure specifically when standing, without worsening supine hypertension. Has anyone had experience with this medication, especially in the context of Parkinson’s or MSA-related orthostatic hypotension?

Hoping it might be a good combo that stabliises BP for her to try levodopa.