Chancellor George Osborne's psychiatrist brother has been struck off the medical register after admitting to a two-year sexual relationship with a vulnerable patient.
Adam Osborne, who is five years younger than his brother, threatened the mother-of-two when she reported him to the General Medical Council (GMC), telling her "I will make sure you pay" after he ended the affair by email.
The Medical Practitioners Tribunal Service (MPTS) ruled that his fitness to practise was impaired by reason of misconduct and that the married doctor's behaviour was "profoundly unacceptable".
Dr Osborne did not attend the four-day disciplinary hearing in Manchester which heard how the woman - referred to as Patient A - took an overdose of alcohol and prescription drugs in an attempt to end her own life two days after he broke off the relationship.
Dr Osborne, who has been helping Syrian refugees in Calais, qualified as a doctor in 2004.
He admitted all the allegations he faced.
The hearing was told he had been treating Patient A at a private practice in central London for depression, anxiety and chronic fatigue between February 2011 and late 2014.
Following the split in February last year, the woman told him: "I'm very much balancing on the edge and it's so easy for me to tip over just now."
Despite knowing of her fragile state and suicide attempt, he bombarded her with threatening emails over a 10-day period begging her to retract her complaint.
He pleaded: "You still have the power to tell the GMC that you made this up because you were angry at me for discontinuing therapy or that you were confused, paranoid, deluded - whatever excuse you can think of."
He also told her: "If I get into trouble for this then I will never forgive you for this and I will make sure you pay."
Another email read: "Please don't do this to me, it will destroy me and my family in public."
The tribunal was told that Dr Osborne's wife had knowledge of the woman.
His counsel Julian Woodbridge said: "Dr Osborne accepts that he did engage in an inappropriate relationship with the patient, Patient A, and he apologises for his conduct in this respect.
"Dr Osborne also accepts that after he tried to end the relationship he did subsequently send a number of inappropriate emails in a moment of panic. Again he apologises and much regrets any further distress."
MPTS panel chairman Dr Nigel Callaghan said that Dr Osborne's actions were not "easily remediable" and that the affair was "profoundly unacceptable".
Dr Callaghan added: "Having determined that neither conditions nor a suspension order would adequately reflect the seriousness of the tribunal's findings on impairment it determined that Dr Osborne's name should be erased from the medical register.
"The tribunal considers that erasure is the only appropriate sanction which will protect patients and maintain public confidence in the profession.
He added: "His behaviour towards Patient A has caused her harm and the tribunal could not be satisfied that there would be no repetition of this misconduct.
"The tribunal has determined that Dr Osborne has shown a blatant disregard for the fundamental tenets of the medical profession."