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Nonspecific medication side effects and the nocebo phenomenon.

Patients taking active medications frequently experience adverse, nonspecific side effects that are not a direct result of the specific pharmacological action of the drug. Although this phenomenon is common, distressing, and costly, it is rarely studied and poorly understood. The nocebo phenomenon, in which placebos produce adverse side effects, offers some insight into nonspecific side effect reporting. We performed a focused review of the literature, which identified several factors that appear to be associated with the nocebo phenomenon and/or reporting of nonspecific side effects while taking active medication: the patient's expectations of adverse effects at the outset of treatment; a process of conditioning in which the patient learns from prior experiences to associate medication-taking with somatic symptoms; certain psychological characteristics such as anxiety, depression, and the tendency to somatize; and situational and contextual factors. Physicians and other health care personnel can attempt to ameliorate nonspecific side effects to active medications by identifying in advance those patients most at risk for developing them and by using a collaborative relationship with the patient to explain and help the patient to understand and tolerate these bothersome but nonharmful symptoms.

Attitude to Health↗

Understanding placebo, nocebo, and iatrogenic treatment effects.

Placebo and nonplacebo treatments have both positive and negative effects on patient outcomes. To better understand the patterning of treatment effects, three specific interventions will be discussed that are reported to produce more harm than benefit: critical incident stress debriefing, group therapy for adolescents with conduct disorders, and psychotherapy for dissociative identity disorder. In each case, there is an interaction between mechanisms thought to underlie both placebo and specific treatment effects. Mechanisms hypothesized to underlie placebo and nocebo effects include patient expectancy, self-focused attention to symptoms, motivation to change, and sociocultural role-enactment cues. In the three treatments discussed, specific mechanisms interact with nonspecific mechanisms to produce iatrogenic effects. To advance knowledge, it is important both to specify the theory of treatment and its expected outcomes and to put the theory to test. Only with attention to the empirical findings from programmatic research of specific and nonspecific effects and their interaction is it possible to improve the outcomes of treatment beyond the status quo.

Humans↗

Iopentol in urography. A clinical comparison between iopentol and metrizoate including delayed reactions.

A double-blind comparative study of the nonionic contrast medium iopentol and the ionic contrast medium metrizoate for urography was carried out in 200 adult outpatients. Significantly less discomfort and other side effects were observed following iopentol than following metrizoate. No serious adverse reactions and no clinically significant alterations in heart rate or blood pressure were observed. A questionnaire was used to record delayed symptoms, from 30 min after contrast medium injection and for one week. The response rate was 92% and delayed adverse events were reported by 45%. The incidence of delayed reactions was significantly lower following iopentol than following metrizoate, i.e., delayed arm pain, fatigue, headache, diarrhea, nasal congestion, and rash. Delayed arm pain was probably due to contrast medium induced thrombosis in 1% following iopentol and in 8% following metrizoate. Most other symptoms were probably related to a combination of nocebo effect and coincidentally occurring symptoms. The urograms with both media were of similar high quality. Iopentol was found a suitable contrast medium for urography.

Adult↗

Current and Future Perspectives of LDL-C Lowering Therapies 2026.

LDL cholesterol (LDL-C) is the central causal factor for atherosclerotic cardiovascular disease (ASCVD), and its reduction is a cornerstone of both primary and secondary prevention. Since the introduction of statins more than three decades ago, LDL-C-lowering therapy has expanded substantially, now encompassing ezetimibe, proprotein convertase subtilisin/kexin type 9 (PCSK9)-targeting agents, bempedoic acid, and other emerging modalities. This expanding therapeutic landscape has improved the feasibility of achieving guideline-recommended LDL-C targets, but it has also increased the complexity of clinical decision making. This review provides a contemporary and practical overview of the LDL-C-lowering strategies, beginning with the initial evaluation of patients with elevated LDL-C, including differentiation between primary and secondary causes and the identification of familial hypercholesterolemia (FH). We summarize the current treatment targets for primary and secondary prevention, highlight the optimal selection and use of statins, and discuss the assessment and management of statin intolerance, including the role of the nocebo effect. Non-statin therapies, including ezetimibe, bile acid sequestrants, PCSK9 inhibitors, inclisiran, and bempedoic acid, are reviewed with an emphasis on their mechanisms, efficacy, and clinical positioning. Advanced therapies for severe dyslipidemia, such as lipoprotein apheresis, lomitapide, and evinacumab, are also discussed in this review. Finally, we outline the future directions, including oral PCSK9 inhibitors, next-generation cholesteryl ester transfer protein (CETP) inhibitors, lipoprotein(a)-lowering agents, and genome-editing approaches. Collectively, these developments offer new opportunities to address unmet clinical needs, particularly in patients with FH, statin intolerance, and residual cardiovascular risk. A comprehensive understanding of these therapies is essential for further reducing the burden of ASCVD in the coming decades.

Humans↗

Conscious expectation and unconscious conditioning in analgesic, motor, and hormonal placebo/nocebo responses.

The placebo and nocebo effect is believed to be mediated by both cognitive and conditioning mechanisms, although little is known about their role in different circumstances. In this study, we first analyzed the effects of opposing verbal suggestions on experimental ischemic arm pain in healthy volunteers and on motor performance in Parkinsonian patients and found that verbally induced expectations of analgesia/hyperalgesia and motor improvement/worsening antagonized completely the effects of a conditioning procedure. We also measured the effects of opposing verbal suggestions on hormonal secretion and found that verbally induced expectations of increase/decrease of growth hormone (GH) and cortisol did not have any effect on the secretion of these hormones. However, if a preconditioning was performed with sumatriptan, a 5-HT(1B/1D) agonist that stimulates GH and inhibits cortisol secretion, a significant increase of GH and decrease of cortisol plasma concentrations were found after placebo administration, although opposite verbal suggestions were given. These findings indicate that verbally induced expectations have no effect on hormonal secretion, whereas they affect pain and motor performance. This suggests that placebo responses are mediated by conditioning when unconscious physiological functions such as hormonal secretion are involved, whereas they are mediated by expectation when conscious physiological processes such as pain and motor performance come into play, even though a conditioning procedure is performed.

Aged↗

[Nocebo--the antipode to placebo].

It is well documented that placebo represents Pavlovian conditioned reflexes activated by positive anticipation of healing. The pain-relieving effects of placebo are due to a psychical activation of the endogenous opioid-serotonergic, pain-inhibitory descending system. The opposite effect is nocebo, a term introduced in 1961 by Kennedy. Nocebo-effects similarly appear to be produced by conditioned reflexes, but are activated by negative expectations (Figure 1). A number of examples of nocebo are given. Nocebo-stimuli, such as anxiety, fear, mistrust and doubt, may reduce a placebo-effect; it may induce negative side-effects in placebo-treatment; it may produce new aversive symptoms; and it may reverse symptoms from positive ones to negative ones (e.g. revert an analgesic response to hyperalgesia). In its most extreme, nocebo-stimuli may cause death, as in voodoo-death in primitive societies, an example of the fear-paralysis reflex. Whether the outcome is positive or negative is determined, inter alia, by the subject's possibility of coping with the situation. In a setting where the animal has no control over an aversive stimulus, as in inescapable foot shocks, nocebo-effects predominate. It is postulated that noradrenergic neurons in locus coeruleus in the brain stem are involved in the production of nocebo-effects. The "placebo-system" and the "nocebo-system" exert a reciprocal inhibition at a brainstem level (Figure 3).

Drug-Related Side Effects and Adverse Reactions↗

[Nocebo--the opposite of placebo].

It is well documented that placebo represents Pavlovian conditioned reflexes activated by positive anticipation of healing. The pain-relieving effects of placebo are due to a psychical activation of the endogenous opioid-serotonergic, pain-inhibitory descending system. The opposite effect is nocebo, a term introduced in 1961 by Kennedy (10). Nocebo-effects similarly appears to be produced by conditioned reflexes, but are activated by negative expectations (fig 1). A number of examples of nocebo are given. Nocebo-stimuli, such as anxiety, fear, mistrust and doubt, may reduce a placebo-effect; it may induce negative side-effects in placebo-treatment; it may produce new aversive symptoms; and it may reverse symptoms from positive ones to negative ones (e.g. revert an analgesic response to hyperalgesia). In its most extreme, nocebo-stimuli may cause death, as in voodoo-death in primitive societies, an example of the fear-paralysis reflex. Whether the outcome is positive or negative is determined, inter alia, by the subject's possibility of coping with the situation. In a setting where the animal has no control over an aversive stimulus, as in inescapable foot shocks, nocebo-effects predominate. It is postulated that noradrenergic neurons in locus coeruleus in the brain stem are involved in the production of nocebo-effects. The "placebo-system" and the "nocebo-system" exert a reciprocal inhibition at a brainstem level (fig 3).

Animals↗

Placebos in medicine.

Although placebo may be defined as a treatment that does not have a specific effect on the illness for which it is being used, or as an intervention for which there is no scientific theory explaining its mechanism of action, placebo can be an effective therapeutic intervention. Placebo can be administered as a drug or as a procedural intervention. Multiple factors affect the ultimate intensity of the placebo response. One of these factors is the approach taken by the health care provider in administering an intervention. The medical literature is replete with clinical studies showing beneficial results of placebo administration. Physicians should attempt to better understand placebo to harness its beneficial effects, avoid nocebo or negative effects, and maximize the placebo response.

Adult↗

[Placebos and nocebos].

Placebo effects are common in the treatment of pain. This paper summarizes present knowledge on the placebo response, its frequency, its problems, the suspected mechanisms of placebo effects and ethical and legal aspects of the intentional application of placebos. Clinical situations are described in which the use of placebos may be considered and conditions for its critical application are proposed.

Ethics, Medical↗

Neurophysiologic correlates of side effects in normal subjects randomized to venlafaxine or placebo.

Adverse events reported in the context of medication administration may be due to pharmacodynamic and/or nonpharmacodynamic effects (eg, nocebo phenomena). Neurophysiological substrates of side effects may be examined in placebo-controlled antidepressant treatment trials. We explored the relationship between side effects and regional neurophysiologic changes in normal subjects receiving a 1-week placebo lead-in followed by 4 weeks randomized treatment with placebo (n = 15) or venlafaxine IR (n = 17). Quantitative electroencephalographic (QEEG) cordance measures were obtained before and during treatment, and side effects were assessed weekly using semistructured interviews. Side effect burden, characterized as the mean number of side effects per postrandomization visit, correlated significantly with neurophysiologic changes in the antidepressant group but not the placebo group. Medication group side effects were negatively correlated with changes in prefrontal cordance at end of placebo lead-in (r = -0.67, p < 0.003), at 2 weeks (r = -0.77, p < 0.002), and at 4 weeks (r = -0.77, p < 0.004) post randomization. After controlling for the prefrontal change at the end of placebo lead-in, postrandomization brain changes did not further explain side effect burden. Changes in prefrontal brain function associated with later antidepressant side effects were observed during placebo lead-in-prior to the administration of medication. Prefrontal brain function during brief placebo administration may help explain susceptibility to the development of antidepressant side effects. Results of these exploratory hypothesis-generating analyses should be considered tentative until replicated.

Adolescent↗

[Placebo: an unappreciated factor in medicine].

Placebo is a provoking factor in medicine that is discussed controversially and not fully understood so far. From the scientific point of view and according to evidence-based medicine a proved indication to prescribe a placebo does not exist. Therapy of pain may be an exclusion. In our daily work we consciously use the placebo-effect, but on the other hand we are committed to the placebo-phenomenon. This article gives an overview of various aspects of placebo. The currently supported theory about the placebo response, conditioning and expectancy, are discussed. Further, the side effects (nocebo-phenomenon) and the utility of placebo in randomised clinical trials is highlighted.

Controlled Clinical Trials as Topic↗

Hypnosis in the 1990s--and beyond.

For this Presidential Address, I accepted the challenge to discuss my perception of the future directions of hypnotherapy. I believe that the next decade will bring increased attention to the mind/body relationship and how hypnosis can be most effectively employed in this area. As an oncologist, one of the most exciting areas of current research is in psychoneuroimmunology. The role of communication in the practice of the health sciences is receiving more emphasis. Training in hypnosis is helpful in recognizing spontaneous trance states which may modify the effects of "nocebos." The use of hypnoanesthesia for surgery would be ideal in third world and developing countries. I believe there will be increased interest in the use of hypnosis in self-care, in the forensic area, and in the use of self-hypnosis by the general population. Finally, I expect that in the next decade the ASCH and SCEH will cooperate more closely in many areas of significance to hypnosis.

Forecasting↗

The effects of manipulating expectations through placebo and nocebo administration on gastric tachyarrhythmia and motion-induced nausea.

BACKGROUND: Interest in the role of expectation in the development of nausea and other adverse conditions has existed for decades. The purpose of this study was to examine the effects of manipulating expectations through the administration of placebos and nocebos on nausea and gastric tachyarrhythmia provoked by a rotating optokinetic drum. METHOD: Seventy-five participants were assigned to one of three groups. Positive-expectancy group participants were given placebo pills that would allegedly protect them against the development of nausea and motion sickness. Negative-expectancy group participants were given the same pills as nocebos; they were led to believe there was a tendency for them to make nausea somewhat worse. Placebo-control group participants were told the pills were indeed placebos that would have no effect whatsoever. RESULTS: Subjective symptoms of motion sickness were significantly lower among negative-expectancy group participants than positive-expectancy and placebo-control group participants (p<0.05). Gastric tachyarrhythmia, the abnormal stomach activity that frequently accompanies nausea, was also significantly lower among negative-expectancy group participants than positive-expectancy and Placebo-Control Group participants during drum rotation (p<.05) [corrected] CONCLUSIONS: Inducing negative expectations through nocebo administration reduced nausea and gastric dysrhythmia during exposure to provocative motion, whereas positive placebos were ineffective for preventing symptom development. That manipulation of expectation affected gastric physiological responses as well as reports of symptoms, suggests an unspecified psychophysiological mechanism was responsible for the observed group differences. These results also suggest that patients preparing for difficult medical procedures may benefit most from being provided with detailed information about how unpleasant their condition may become.

Adolescent↗