Leon Eisenberg (August 8, 1922 – September 15, 2009) was an American child psychiatrist, social psychiatristThe Creation of Psychopharmacology, David Healy, 2002, cites Eisenberg's role in evidence-based social psychiatry and medical educator who "transformed child psychiatry by advocating research into developmental problems".

He received both his BA and MD degrees from the Perelman School of Medicine at the University of Pennsylvania.

He is credited with several "firsts" in medicine and psychiatry – in child psychiatry, autism, and the controversies around autism, randomized clinical trials (RCTs), social medicine, global health, affirmative action,Shanks Thirty Years of Affirmative Action at Harvard Medical School: A Mixed Method Program Evaluation, U Mass EdD Thesis by Alane Shanks (2004) and evidence-based psychiatry.

He served as Chairperson of the Johns Hopkins Hospital Department of Child and adolescent psychiatry and Harvard Medical School until his retirement in 1988. After retirement, he continued as The Maude and Lillian Presley Professor of Social Medicine, Psychiatry Emeritus, and in the Department of Global Health and Social Medicine of the Harvard Medical School in the Longwood Medical Area of Boston, until a few months before his death in 2009. Previously, he had taught at both the University of Pennsylvania and Johns Hopkins University. He was chief of psychiatry at both Johns Hopkins Hospital in Baltimore and the Massachusetts General Hospital in Boston during formative periods in psychiatry for each institution.Leon Eisenberg papers, 1905-2009 (inclusive), 1968-2005 (bulk). HMS c196. Harvard Medical Library, Francis A. Countway Library of Medicine, Boston, Mass.

Medical accomplishments Eisenberg completed the first outcome study of autistic children in adolescence and recognized patterns of language use as the best predictor of prognosis. Of the two first studies of the outcome of infantile autism, he reported the American study in the American Journal of Psychiatry in 1956, and the UK study was reported in JCPP shortly afterward by Victor Lotter and Sir Michael Rutter. Eisenberg also studied and identified the use of rapid rea turn to school as the key treatment in the management of the separation anxiety in an underlying school phobia.

He was principal investigator (PI) on the first grant from the Psychopharmacology Branch of NIMH for RCTs in child psychopharmacology. From a concern for evidence-based care, well before the phrase was coined, he introduced randomized controlled trials (RCTs) in psychopharmacology and showed that "tranquillizing drugs were inferior to placebo in the treatment of anxiety disorders, whereas stimulant drugs were effective in controlling hyperactivity."

Eisenberg completed the first RCTs of psychiatric consultation to social agencies and the utility of brief psychotherapy in anxiety disorders. He published a forceful critique of Konrad Lorenz's instinct theory and established the usefulness of distinguishing "disease" from "illness". He has highlighted the environmental context as a determinant of the phenotype emerging from a given genotype, and from the late 1990s through 2006, he had been involved with developing conferences and resources for medical educators in various specialties that would help them incorporate into courses with their current and future students, the tidal wave of new information in genomics yet to puzzle future clinicians. This interest may have been encouraged by his stepson, Alan Guttmacher, then acting head of the National Human Genome Research Institute. For many decades, Eisenberg had criticized psychoanalysis from several platforms.

The scientific contributions of Eisenberg include: The first longitudinal follow-up of Leo Kanner's original cases of autism. A study that identified the roots of social phobia in parental anxiety. The first clinical trial in search of the effectiveness of psychiatric consultation in a social agency. The first randomized controlled trial in childhood psychopharmacology.. The first randomized controlled trial of stimulant drugs in adolescents. The first randomized clinical trial of brief psychotherapy. A forceful critique of Lorenz's theory of instincts and imprinting. An early statement of the distinction between "disease" (what doctors deal with) and "illness" (what patients suffer). A widely cited critique of the oscillation of psychiatry between brain-centered and mind-centered that approaches arguing for the integration of the two. A synthesis of the evidence on the importance of training primary care physicians to recognize and treat depression. Papers that highlight molding the brain structure by social experience. Publications putting inheritance in an environmental context as a determinant of risk and resilience. Eisenberg is known as "the father of prevention science in psychiatry"

Eisenberg was proudest of the Diversity Lifetime Achievement Award he received in 2001 for his role in inaugurating affirmative action at HMS in 1968 and sustaining it as chairman of the Admissions Committee from 1969 to 1974. He regards that as his most important contribution to Harvard Medical School.

He and his wife, Carola B. Eisenberg, former dean of students, first at MIT, then at Harvard Medical School, had been active with Physicians for Human Rights, which as an organization received a Nobel Peace Prize in 1997 for its International Campaign to Ban Landmines.

In mid-2009 (June 22, 2009), a Leon Eisenberg Chair in Child Psychiatry was named at Children's Hospital Boston. The first chairholder of the Leon Eisenberg Professorship in Child Psychiatry is David R. DeMaso, MD, HMS Professor of Psychiatry and Psychiatrist-in-Chief at Children's Hospital Boston.

His autographical memoir was published posthumously by Acta Psychiatrica Scandinavica.

Death Eisenberg died of prostate cancer at his home in Cambridge, Massachusetts on September 15, 2009.Benedict Carey, Dr. Leon Eisenberg, Pioneer in Autism Studies, Dies at 87 The New York Times. Retrieved on October 3, 2009.

Later autobiographical reflections: "Were We Asleep at the Switch?" Eisenberg wrote a 'mini-autobiography' which he named "Were We Asleep at the Switch?". Eisenberg suggested that a switch from 'mind' to 'body' has taken place in psychiatry as a discipline, which led to overuse of medication. He also argued that, while medical scientists were worrying about the tedious science at the base of medical practice and healthcare decisions for the general public, "money" and monied interests had been making de facto decisions for the populace about how things that affected them deeply were going to be done. In this view, the overwhelming impact of economic considerations over emerging bodies of expert knowledge may have rendered and might continue to render futile the professional contributions of many brilliant, timely, and concerned working scientists.

A 2012 article in the German weekly publication Der Spiegel gives an account of an interview Eisenberg gave in 2009, seven months before his death. It quotes him as saying, "ADHD is a prime example of a fabricated disease... The genetic predisposition to ADHD is completely overrated." Instead of prescribing a 'pill', Eisenberg said, psychiatrists should determine whether there are psychosocial reasons that could lead to behavioral problems.

Earliest papers Bazett H. C. Love L. Newton L. Eisenberg L. Day R. & Forster R. (1948) Temperature changes in blood flowing in arteries and veins in man Pub. J Appl Physiol pp. 1:3-19. Eisenberg L. (1953) Treatment of the emotionally disturbed pre-adolescent child Pub. Proc Child Research Clinic Woods Schools 35:30-41. Kanner L. & Eisenberg L. (1955) Child psychiatry; mental deficiency Pub. American Journal of Psychiatry, 111:520-523. Eisenberg, L. (1956), The autistic child in adolescence Pub. American Journal of Psychiatry 112, pp. 607–612. Reprinted in: Alexander et al., eds. Psychopathology Cambridge: Harvard University Press, 1959. Kanner L. & Eisenberg L. (1956) Child psychiatry; mental deficiency Pub. Am J Psychiat, 112:531-534. Kanner, L. & Eisenberg L. (1956) Early Infantile Autism 1943–1955 Pub. American Journal of Orthopsychiatry 26, pp. 55–65. Reprinted in: Alexander et al., eds. Op. cit. Reprinted in Psychiat. Res. Repts. 1957 (April), American Psychiatric Assn., pp. 55–65. Eisenberg L. (1956) The parent-child relationship and the physician Pub. AMA J Dis of Children, 91:153-157. Eisenberg L. (1956) Dynamic considerations underlying the management of the brain-damaged child Pub GP, 14:101-106. Glaser K & Eisenberg L. (1956) Maternal deprivation Pub. Pediatrics, 18:626-642. Kanner L & Eisenberg L. (1957) Child psychiatry: mental deficiency Pub. Am J Psychiat, 113:617. Eisenberg L. (1957) Psychiatric implications of brain damage in children Pub. Psychiatric Quarterly, 31:72-92. Eisenberg L. (1957) Progress in neuropsychiatry Pub. J Ped, 51:334-349. Eisenberg L. (1957) The course of childhood schizophrenia Pub. Arch Neurol Psychiat, 78:69-83. Kanner L. & Eisenberg L. (1957) Childhood problems in relation to the family Pub. Pediatrics, 20:155-164. Eisenberg L. (1957) The fathers of autistic children Pub. American Journal of Orthopsychiatry, 27:715-724. Kanner L. & Eisenberg L. (1958) Child psychiatry; Mental Deficiency Pub. Am J Psychiat, 114:609-615. Eisenberg L. (1958) School phobia: a study in the communication of anxiety Pub. Am J Psychiat, 114:712-718. Reprinted in: Trapp EP and Himmelstein P, eds. Readings on the exceptional child. New York: Appleton, 1962. Reprinted in: Bobbs-Merrill Reprint Series in the Social Sciences, 1966, p. 433. Reprinted in: Davids A, ed. Issues in abnormal child psychology. California: Brooks/Cole, 1973. Eisenberg L. (1958) Discussion: roundtable symposium on desegregation (segregation-integration) Pub. Am J Orthopsychiat, 28:33-35. Eisenberg L. (1958) An evaluation of psychiatric consultation service for a public agency Pub. Am J Public Health, 48(6):742-749. Eisenberg L. (1958) Emotional determinants of mental deficiency Pub. Arch Neurol Psychiat, 80:114-121. Eisenberg L. (1958) Diagnosis, genesis, and clinical management of school phobia Pub. Ped Clin North America, 645–666. Eisenberg L. Marlowe B. & Hastings M. (1958) Diagnostic services for maladjusted foster children: An orientation toward an acute need Pub. Am J Orthopsychiat, 28(4):750-763. Kanner L & Eisenberg L. (1959) Child psychiatry and mental deficiency Pub. Am J Psychiat, 115:608-611. Eisenberg L. Ascher E. & Kanner L. (1959) A clinical study of Gilles de la Tourette's disease (maladie des tics) in children Pub. Am J Psychiat, 115:715-523. Eisenberg L. (1959) Office evaluation of specific reading disability in children Pub. Pediatrics, 23(5):997-1003. Rodriguez A, Rodriguez M, & Eisenberg L. (1959) The outcome of school phobia: a follow up study Pub. Am J Psychiat, 116:540-544. Eisenberg L. (1959) The pediatric management of school phobia Pub. J Pediatrics, 55(6):758-766. Eisenberg L. (1960) Child psychiatry; mental deficiency Pub. Am J Psychiat, 116:604. Eisenberg L. (1960) Conceptual problems in relating brain and behavior Pub. Am J Orthopsychiat, 30:37-48. Cytryn L. Gilbert A. & Eisenberg L. (1960) The effectiveness of tranquilizing drugs plus supportive psychotherapy in treating behavior disorders of children Pub. Am J Orthopsychiat, 30:113-129. Eisenberg L. (1960) The challenge of change Pub. Child Welfare, 39:11-18. Lesser L. Ashenden B. Debuskey M. & Eisenberg L. (1960) A clinical study of anorexia nervosa in children Pub. Am J Orthopsychiat, 30:572-580. Eisenberg L. and Gruenberg E. (1961) The current status of secondary prevention in child psychiatry Pub. Am J Orthopsychiat, 31:355-367.