A former doctor at Mount Sinai Hospital in Manhattan was arraigned on Thursday on charges of sexually abusing four women who came into the emergency room there, touching their breasts for no medical reason and, in one case, drugging, groping and masturbating on a patient.

The physician, Dr. David H. Newman, pleaded not guilty before Justice Michael J. Obus in State Supreme Court in Manhattan to one count of first-degree sexual abuse and four counts of third-degree sexual abuse. He remains free on bail.

“Four young women who came to the hospital for medical treatment were sexually abused by the very doctor entrusted with their care,” the Manhattan district attorney, Cyrus R. Vance Jr., said in a statement. “One was sedated to the point of being physically helpless — a nightmare scenario for any patient to endure.”

Dr. Newman’s lawyer, Susan R. Necheles, said he vigorously denied the charges and expected to prove at trial that they were false.