Otto Ernst Guttentag was born in Stettin, Pomerania, Germany, into a family with three generations of physicians before him. He studied for the degree "Candidate in Medicine" at Marburg, Jena and Heidelberg and for the title "Physician" at Munich, Berlin and Halle. In 1924 he received the M.D. degree with highest honors after a year of independent work supervised by the distinguished nephrologist Franz Volhard. He remained with Volhard at Halle, then at Frankfurt, until the Nazis took power in 1933, at which time he accepted a previously extended invitation from the Homeopathic Foundation of California to become director of that institution's research laboratory in San Francisco.

At the time he left Frankfurt, Guttentag was in charge of a 50-bed research ward, programmed to evaluate critically the effectiveness of homeopathic treatment, then an alternative mode used by many physicians. He had prepared himself for this with advanced studies in biochemistry and pharmacology, and in his clinical trials he was using double-bind techniques similar to those preferred today. Interested for some years in homeopathy because of the attention given by its advocates to human biologic diversity, he had been skeptical of its pharmacologic aspect.

For a brief time, Guttentag conducted studies and published from the Homeopathic Foundation of California, and he remained over the years interested in developments relating to the homeopathic tradition. However, in 1936 the Hahnemann Medical College of the Pacific merged with the University of California Medical School, where an endowed chair of Homeopathy was created in the Department of Medicine for Guttentag (some years later, his title was changed to "Samuel Hahnemann Professor of Medicine and Medical Philosophy"). Here he became rapidly assimilated into the culture of the medical school. He attended rounds and conferences of the Department of Medicine, both on the campus and at the County Hospital. He established the department's first renal clinic and later, with his growing interest in physical anthropology, an obesity clinic. His primary teaching vehicle was an elective seminar that was offered annually until the last months of his life, first under the title "Homeopathy," and later "The Medical Attitude" and "Role of the Attending Physician."

Dr. Guttentag obtained U.S. citizenship in 1940. He volunteered for service in the U.S. Army as a medical officer in World War II, participated in D-Day, and was stationed in Germany for a number of months during the occupation. He was there again for an extended period in 1947 after being appointed by the American military government to help with the rehabilitation of the German medical schools.

Dr. Guttentag's stature and his writings on medical philosophy and ethics influenced the national debate concerning the impact of the biotechnological revolution on the welfare of patients. In May of 1951, he participated in a pioneering symposium at UCSF, later published in Science, on the problem of experimentation on humans. Guttentag published other papers and delivered lectures in this area such as "Rights and Duties in Medical Practice," "Science and Morality in Medicine," and "The Humanities and the Profession of Medicine." In 1963 he became the principal investigator of a grant proposal by the National Institutes of Health to look at the impact of medical science on medical morality and ethics by means of a national survey of medical educators. The results appeared as a book, Science and Morality in Medicine, by Earl R. Babbie.

Dr. Guttentag reached the age of mandatory retirement in 1967 but was recalled annually, kept an office, and continued his usual activities into the last year of his life. In 1978 he received the annual award of the Society for Health and Human Values of the National Association of Scholars and Teachers of the Humanities. In 1979, he gave the opening address at a Hastings Symposium held in his honor at Cornell under the title "Changing Values in Medicine." In 1980, UCSF awarded him its highest honor, the UCSF Medal, and in the same year he was made an honorary member of the Medical School's Gold-Headed Cane Society, in recognition of his contributions to the teaching and practice of medicine.

Otto Guttentag died in 1991.