Jeremy Howick, The Power of Placebos: How the Science of Placebos and Nocebos Can Improve Health Care (Johns Hopkins University Press: 2023) 320 pp. $32.95 Hb. ISBN: 9781421446387
Can the solution to the opioid crisis—and perhaps even the superbug problem—lie in using less medication, without compromising pain relief or curability? Professor and Director of Empathic Healthcare at the University of Leicester, Jeremy Howick, argues that it can. His new book, The Power of Placebos: How the Science of Placebos and Nocebos Can Improve Health Care, offers a bold yet grounded proposal: to make ethical placebos a mainstream tool in medicine, and to eliminate nocebos from clinical practice. But do we truly understand what a nocebo, or for that matter a placebo, is? And what exactly makes a placebo ethical? Howick unpacks these questions through the book. Citing the lack of consensus in a definition for the term, the book puts forth a formal definition for placebos (30): ‘Placebos are complex treatments whose core components such as (part of) a pill, injection, or even surgical procedure are inert relative to the disorder but when given in a meaningful context can have a beneficial effect’. Ethical, honest or open-label placebos, the book also explains, are administered with full patient awareness that they are receiving a placebo, yet they still produce measurable benefits. Nocebos, by contrast, are the negative counterparts: when the expectation of harm or side effects itself causes distress.
The book opens with a striking question: do we really need a new revolution in placebo studies given that the science has been around for decades? Howick’s answer is an emphatic yes. Despite widespread awareness of the term ‘placebo,’ he argues that confusion and inconsistency still surround its definition. Are placebos pharmacologically inert substances with real therapeutic effects? Or are they non-specific components of therapy with no active ingredient? The lack of consensus, he shows, has hindered both research and acceptance of the science into mainstream healthcare. In Chapter 1, ‘A Manifesto for the Next Revolution in Nocebo and Placebo Studies’, Howick traces the fragmented history of placebo research and recounts how pioneers fought to legitimize it within medical science, giving rise to what he describes as the first revolution. Despite progress, he argues, the field remains sidelined in clinical practice. The second revolution, then, must focus on integration: moving placebo knowledge from the laboratory to the bedside. The author proposes the book as a practical manual for a wide audience—researchers, clinicians, philosophers of medicine, and ethicists—organized into three parts: Part I defines placebos and nocebos, rebuffing claims that they do not exist and showing how they are already commonplace in modern medicine, albeit not in the right context. Part II explores the mechanisms that shape these effects, and how to (and how not to) measure them. Part III finally tackles how placebos are currently used, identifies shortcomings in those practices, and builds a case for why there is an ethical requirement to prescribe honest placebos more actively and to minimize nocebos in healthcare.
Howick attempts to keep the book accessible to audiences with wide-ranging expertise. In catering to a diverse crowd, however, he occasionally risks oversimplification. For example, his use of anecdotal examples—unnamed Italian doctors, unpublished experiments, or statements about how kinder doctors and greener hospital rooms aid recovery—sometimes read as generic rather than rigorously evidenced. Yet these moments do not detract from the book’s overall clarity and ambition. The book gains considerable depth in Chapter 6. After pages of describing the what, Howick pivots to the mechanisms—how and why—placebos work. Far from being purely psychological, he argues, placebo effects can manifest measurable pharmacological responses: peak, cumulative, and carryover effects that mimic those of active drugs. He subsequently connects the placebo effect to the body’s ‘feed and breed’ (relaxation) response, and the nocebo effect to the ‘fight or flight’ (stress) response in an elegant and intuitive framework that captures the power of expectation and context in healing (111-113). This association situates placebo and nocebo phenomena within broader psychophysiological frameworks, illustrating with an example, how placebo effects can influence the body’s immune responses. The implications of this are both intuitively appealing and intellectually provocative, residing just beyond the threshold of obviousness, but grounded in empirical plausibility.
As the book unfolds, initial confusion about the messiness of definitions, trials, and studies gives way to an appreciation of how the field of placebo and nocebo research reflects the chaos of the human psyche. In the final section, Howick draws on studies of open-label placebos—where patients who are fully aware of receiving a placebo still show improvement in symptoms—to debunk the most popularly perpetrated myth surrounding placebos: that their use requires deceiving patients. Indeed, he argues that not using placebos, when they could enhance outcomes, might in itself be unethical. To his credit, Howick acknowledges small sample sizes and imperfect study designs in the evidence he cites, remaining transparent about their limitations. Ultimately, The Power of Placebos succeeds as both a comprehensive, if lacking-in-depth, synthesis and a call to action for more proactive and deliberate use of placebos. Howick demonstrates that placebo and nocebo effects are neither anomalies nor curiosities but fundamental components of the healing process. His call to rethink the implementation of the science is grounded in the conviction that medicine must embrace the therapeutic potential of context, expectation, and meaning—without sacrificing scientific integrity or patient autonomy.
The Power of Placebos showcases why healthcare science stands to benefit from the systematic incorporation of placebos, first emphasizing the need for a unanimous definition, then building an appreciation for the complexity of the science and instructing how to accurately assess its effects, and finally detailing how to incorporate placebos into mainstream healthcare. Focusing on breadth over depth, Jeremy Howick has written a book that can be used by a multitude of professionals—healthcare providers, hospital designers, placebo researchers, philosophers, and ethicists. Howick’s book ultimately delivers on its promise, offering a clear and thoughtful call to action for a second revolution in placebo and nocebo studies.
Ashitha B. Arun, National Centre for Biological Sciences – Tata Institute of Fundamental Research
