After receiving his medical degree, Brush opened his practice in
Buffalo, New York. He served as editor for
The Buffalo Journal of Medicine and Surgery from March 1874 He stayed until his retirement in 1920. He was a professor of psychiatry at the
College of Physicians and Surgeons in Baltimore until 1920. He continued to serve on the editorial Board and as editor of
The American Journal of Insanity, which became
The American Journal of Psychiatry in 1921 when it was bought by the
American Psychiatric Association (APA). Brush became editor emeritus in 1931. Brush was active in
psychiatric and
mental health activities throughout his professional life. His editorial positions gave him a window on psychiatric activities in the country. He was influential among psychiatric and lay groups. He joined the
American Neurological Association in 1890. He served as President of the Baltimore Medical Society in 1908, and the
Medical Chirurgical Society of Maryland in 1905. He was an honorary member of the
Medico-Psychological Association of Great Britain and Ireland, an honorary member of the
Société Royale de Médecine Mentale de Belgique, and was a Foreign Associate member of the
Société Médico-Psychologique in Paris. He was President of the
American Psychiatric Association from 1915 to 1916. During
World War I, he served on the Advisory Board and the Draft board in Baltimore. In 1902, Brush traveled to Germany to study continental psychiatric clinics. In 1907, he was a delegate to the International Congress of Psychiatry, Neurology and Psychology at Amsterdam. ==Personal life==