Ivan Maxwell was born in the Brocklesby district of southern New South Wales where his father William Maxwell was a grazier. It was then a fairly remote area and he and his elder brother Hubert were taught first by a governess and then by a tutor. When he was twelve years old the family moved to Melbourne where he attended University High School and then undertook the course in agriculture at the University of Melbourne. During his year of practical agriculture at Dookie College, he was awarded the Farrer Gold Medal for an essay on the breeding of wheat. Continuing at the University, he completed the science course and added a period of research in physiology leading to the MSc degree. On the advice of Professor W A Osborne, he extended his training to include medicine in which he graduated with first-class honours in 1918. He proceeded MD (Melbourne) in 1921. For the following two years he was a resident medical officer at the Royal Melbourne Hospital. Later he became an outpatient physician (1927-43) and then physician to inpatients (1943-50).

His initial practice as a physician was in the southern Melbourne suburb of Caulfield: however consequent on his appointment to the Royal Melbourne Hospital in 1927 he established a general medicine consultant practice in the city, with particular interest in the then newly developed specialty of allergy in which he developed a wide reputation as a pioneer. He became an affiliated Fellow of the American Academy of Allergy, a foundation member and president of the Australian Society of Allergists and visiting specialist in allergy to the Repatriation General Hospital, Heidelberg. Pursuing his early scientific training life-long, he retained a close association with the department of biochemistry at Melbourne University in the role of part-time senior lecturer in clinical biochemistry. His Clinical Biochemistry was first published in 1925 and ran to seven editions, the last being published in 1947 and again fully revised in 1956. Other particular interests he pursued, whilst a member of the medical staff of the Royal Melbourne Hospital, were the use of anti-thyroid drugs in hyperthyroidism and the scientific basis of dietetics, the section for which he contributed to the first publication of The Royal Melbourne Hospital Medical Manual, this publication being at his instigation. His therapeutic skills were also manifest in this volume.

Ivan Maxwell’s major contribution to professional, private and public hospital practice during his career was a high clinical standard underpinned prominently by a scientific training and approach. Of his personal qualities Professor VM Trikojus wrote in the Medical Journal of Australia:

Maxwell greatly valued the company of his fellow men, his wide circle of friends including those from many walks of life. Appropriately he was an active member of two long-established clubs, the Wallaby Club (for walking and talking) and Boobooks (for dining and discussion)... He was keenly interested in the Victorian Symphony Orchestra [he held the office of president of The Friends of that body]...He loved travel and made frequent trips overseas where he had many friends and professional colleagues; yet throughout his life he never lost his love of the Australian countryside and personally directed the management of his wheat and sheep property in NSW which he was able to assess by regular quarterly visits. In all his main activities Ivan Maxwell had the constant support of his wife (Lilias Jackson) to whom he was married in 1919. Herself a science graduate and sometime senior demonstrator in physiology in the University of Melbourne, she was ever the gracious hostess in the delightful old family house ‘Narveno’ in Toorak, or at the lovely beachside house at McCrae on Port Phillip Bay.

His widow died in 1972 and he is succeeded by his daughter Marianne (Mrs Kenneth Hunt), son Murray Maxwell FRACP and daughter Rosemary (Mrs M H Fisher, of London).