NEW YORK — More than 100 patients were duped by a “dangerous scam artist” who posed as a clinical psychologist, met with patients in his basement and prescribed antidepressants, prosecutors said Friday.

Donald Lee-Edwards, 43, pleaded not guilty Thursday to criminal impersonation, drug sale, scheme to defraud and other charges.

Prosecutors say the former flight attendant treated patients in a makeshift office in the basement of the Staten Island home he shares with his parents, which was outfitted with treatment rooms, a waiting area and high-tech security equipment.

Authorities say Lee-Edwards would meet with each patient for about two hours and in some cases called pharmacies to fill prescriptions, avoiding the need for a state-issued prescription pad.

They allege he skirted the state’s electronic database that doctors use to prescribe controlled substances by calling in prescriptions for a common generic antidepressant that isn’t required to be entered into the database by either medical practitioners or pharmacists.

“This so-called ‘doctor’ is a dangerous scam artist who never completed any medical school or doctoral program,” Acting Richmond County District Attorney Daniel Master Jr. said. “He merely bestowed upon himself the professional titles of clinical psychologist and medical doctor; he is neither trained nor licensed to provide any mental health or medical services.”

Defense attorney Matthew Blum said there is no evidence Lee-Edwards ever harmed anyone.

“They’re alleging he was some sort of doctor who was operating on people,” Blum said. “They’re turning this guy into a monster. He was really just trying to help some people in his community.”

Detectives began investigating Lee-Edwards in June after patients told police that his unorthodox bedside manner made them question whether he was a doctor. The patients were suspicious because he had discussed other patients and boasted about graduating from high school when he was 13 years old.