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Dr. Claudio A. Naranjo (January 1, 1945 - September 24, 2014) was born in Santiago, Chile.
Dr. Claudio A. Naranjo was a well-respected and prominent Chilean psychopharmacologist, clinical researcher at Sunnybrook Health Sciences Centre, and a Full Professor of Pharmacology, Medicine, and Psychiatry affiliated with the University of Toronto.
He made several significant and pioneering contributions to medicine and psychopharmacology throughout his career: Dr. Naranjo developed the Naranjo Algorithm in 1981, which is an internationally utilized questionnaire/algorithm used to determine the likelihood of an adverse drug reaction. It is used in clinical settings and in drug clinical trials.
The Naranjo algorithm is often compared to the WHO-UMC system for standardized causality assessment for suspected ADRs.
Several investigators, among them Dr. Naranjo with the Naranjo scale, developed logical evaluation methods, or algorithms, for evaluating the probability of an ADR.[2, 20-24] Almost all of these methods employ critical causation variables identified by Sir Austin Bradford Hill in 1965.[6] The most widely accepted of these instruments is the Naranjo algorithm[22] (Table). This method has been tested for internal validity with between-rater reliability testing, and its probability scale has consensual, content, and concurrent validity as well as ease of use in clinical settings and controlled studies.
Dr. Naranjo led the Psychopharmacology Research Program as Head and Senior Scientist at Sunnybrook Health Sciences Centre and Women's College Hospital, focused on the study of psychopharmacology and the mechanisms of depression and brain reward system, geriatric psychopharmacology, fuzzy logic, the study of pharmacokinetics and pharmacovigilance.
Dr. Naranjo is internationally remembered for several key contributions to medicine:
Notably, The Naranjo Algorithm was a widely used causality assessment questionnaire (the "Naranjo scale") to determine the likelihood that an adverse drug reaction is actually caused by a medication rather than the patient's underlying illness. More formal, logical analysis can help differentiate between events that are attributable to a drug from those associated with underlying diseases or other factors, underlying the complexity of detection.[5]
Psychopharmacology Research: Throughout his decades in Toronto, his clinical research heavily focused on the treatment of substance abuse, Alzheimer's disease, and major depressive disorder, clinical trials and drug development.
Academic Legacy: He published hundreds of peer-reviewed papers and was deeply involved in training clinical pharmacology and psychiatry specialists and leaders of tomorrow at the University of Toronto.
He should not be confused with the other prominent psychiatrist of the same name—Dr. Claudio Naranjo (1932–2019)—who was an internationally renowned pioneer of transpersonal psychology, psychedelic therapy, and the Enneagram of Personality, based in California.
References
Naranjo, C A; Busto, U; Sellers, E M; Sandor, P; Ruiz, I; Roberts, E A; Janecek, E; Domecq, C; Greenblatt, D J (1981). "A method for estimating the probability of adverse drug reactions". Clinical Pharmacology and Therapeutics. 30 (2): 239–245. doi:10.1038/clpt.1981.154. ISSN 0009-9236. PMID 7249508. S2CID 29728085.