His preliminary education was obtained in the common schools of the neighborhood and at Rockwood Academy.
The family later moved to Winnipeg and there Ferguson attended Manitoba College.
He began the study of medicine in Winnipeg under Dr. John H. O’Donnell in 1877 and took his Doctor of Medicine degree at Trinity Medical College, Toronto, in 1881.
Ferguson began practise in Buffalo, New York, but returned to Winnipeg in 1882 to be near his aged mother. Here he practised his profession for twelve years.
Shortly after his arrival in Winnipeg he was appointed registrar of the College of Physicians and Surgeons of Manitoba.
The following year Ferguson took the initiative in founding the Manitoba Medical College. In the new faculty he was professor of physiology and histology during the years 1883 - 1886 and professor of surgery from 1886 to 1894. He was surgeon-in-chief of St. Boniface Hospital and a member of the staff of Winnipeg General Hospital.
Ferguson went to Chicago in 1894 to become professor of surgery at the Chicago Post-Graduate Medical School and Hospital, and in 1900 was appointed, together with Dr. Albert J. Ochsner, to the chair of surgery in the medical department of the University of Illinois. He was on the surgical staffs of the Post-Graduate Hospital, the Chicago Hospital, and the Cook County Hospital for the Insane.
His practise in Winnipeg gave him an experience in hydatid disease of the liver such as came to no other man in America and these cases followed him to Chicago.
Ferguson originated a method of treating hernia and improved the technique of cleft palate operations. He was one of the first to advocate decortication of the kidney for chronic Bright’s disease. He contributed more than a hundred articles on surgical subjects to medical periodicals, was the author of a book entitled The Technic of Modern Operations for Hernia (1907), and was engaged upon a text-book of surgery at the time of his death which occurred on October 20, 1911, in Chicago, Illinois, following three months’ illness from septicemia due to a carbuncle.
Alexander H. Ferguson was a member of the British Medical Association and was the first president of the Manitoba branch. He was a fellow of the American Surgical Association, of the American Association of Obstetricians and Gynecologists, and of the Southern Surgical and Gynecological Association, in addition to holding membership in local societies.
Alexander Ferguson was an athlete and foot-ball player in his youth and kept his close-knit, powerful figure to the end. Abounding in energy, he was genial and companionable but with an easily aroused pugnacity.
In 1882, Alexander H. Ferguson married Sarah Jane Thomas of Nassagaweya, Ontario, by whom he had two sons.