Effect of Oxytocin on Placebo Analgesia

Abstract

Placebo responses have been shown to contribute to clinical treatment outcomes. 1 The pharmacological enhancement of placebo responses therefore has the potential to increase treatment benefits. The neuropeptide oxytocin may mediate processes such as empathy, trust, and social learning. 2 These are key elements of the patient-physician relationship, which is an important mediator of placebo responses. 3 We tested whether oxytocin enhances the placebo response in an experimental placebo analgesia model.

Observe to get pain relief: current evidence and potential mechanisms of socially learned pain modulation

“…Despite the limited evidence for the neural mechanisms underpinning socially-induced states of analgesia, hypoalgesia and hyperalgesia, we can speculate that empathy, mentalizing and mirror processes [61], via automatic and cognitively controlled mechanisms [17] and with a potential involvement of the vasopressin and oxytocin systems [14; 29], are engaged in this form of pain modulation. This line of research is highly relevant for pain medicine as well as clinical trial methodology.…”

“…Very recently, it has been shown that the neuropeptide vasopressin [14] and oxytocin [29; 14] boost placebo analgesia induced by verbal suggestions. These hormones are regulated in a sexually dimorphic manner [44] and may be important for observationally-induced pain modulation due their substantial role in regulating social behaviors in humans [20].…”

C-tactile afferents: Cutaneous mediators of oxytocin release during affiliative tactile interactions?

“…For instance oxytocin in placebo controlled trials was shown to reduce the severity of headache and colonic visceral perception in irritable bowel syndrome (Louvel et al, 1996) but produced no beneficial effect in fibromyalgia (Mameli et al, 2014) or pain in chronic constipation (Ohlsson et al, 2005). While oxytocin has been reported to reduce pain and unpleasantness in the cold pressor test and acute laser evoked thermal pain (Paloyelis et al, 2016b) other experimental pain models have not shown a clear anti-nociceptive effect (Kessner et al, 2013;Zunhammer et al, 2015). These discrepancies may relate to differences the mode of administration, dosage, the temporal dynamics of post dose testing as well as disparate trial designs and study populations (see Paloyelis et al, 2016;Tracy et al, 2015).…”

Placebo effects in chronic pain conditions. Can placebo components enhance the efficacy of active treatments?

“…Another interesting study has tested whether the placebo effect can be pharmacologically boosted by the neuropeptide oxytocin in healthy volunteers (Kessner et al 2013a). Oxytocin is involved in processes such as empathy and trust, which are key elements of the patient-practitioner relationship.…”