Flying with Orthostatic Hypotension for Parkinson's patients

My father is 78 years old and suffering from Parkinson's disease since 5 years now. He tested positive for Covid last year and since then his Parkinson's has significantly deteriorated. Post covid, he has developed Orthostatic Hypotension and inspite of taking Fludrocortisone for more than a year now, the difference between his lying and standing systolic BP is on an average 40-50. We were recently told that it's not safe to fly in this condition as the patient may lose consciousness at the time of take off. I want to check if anyone else has/ knows any one with a similar condition and if yes, have you taken a flight / was told it's not safe to fly?