Peter Lange completed a Bachelor of Science degree at the University of Queensland, majoring in physiology and pharmacology. He then completed postgraduate medicine, obtaining an MBBS, internship and early years of training in Queensland. He came to Melbourne in 2005 where he completed physician and geriatrics advanced training at the Royal Melbourne Hospital. He commenced work both in the General Medicine and Geriatrics departments in 2010. In 2012 he was appointed head of the Assessment and Planning Unit at RMH, later renamed the Acute Medical Unit where he was head of unit until stepping down to pursue research in 2021.

In 2016 he took up a PhD with the topic “Delirium in Hospitalised Elderly; changing the Natural History” at the University of Melbourne, representing the formalisation of a research interest in delirium.

He also consults at the Melbourne Private Hospital and Showgrounds Specialist Centre, conducting comprehensive geriatric assessment to determine suitability for Transcutaneous Aortic Valve Implantation.

In 2019 he was appointed Honorary Clinical Associate Professor of the University of Melbourne.

He takes up a post as Director of Geriatrics and General Medicine at Werribee Mercy Hospital in July 2022.