I don’t say this lightly. Your sister’s doctor is a quack.
She should dump him ASAP as this is not the only situation
he might make serious emotion-based errors in judgment.
Firing her doctor was certainly her first reaction however the reality in New York State is no pharmacist will fill the prescription for any Plaque when L or hydroxychloroquine outpatient treatment for covid-19. Her best bet would be trying to find a doctor that would be willing to risk criminal prosecution for ordering hydroxychloroquine for an otherwise approved but falsified condition such as lupus or rheumatoid arthritis.
motoman’s sister needs to get another doctor, and motoman needs to doxx that quack.