Boosting Open-Label Placebo Effects in Acute Induced Pain in Healthy Adults
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: OLP-injection, Scripted Evidence-based treatment rationale, Experimental model of acute pain.
- Who it may be relevant to
- Registry conditions: Acute Pain. Basic parameters: 18 years — 65 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Switzerland
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Overview
This study is to investigate the effect of open-label placebo (OLP) application on acute pain in an experimental model of acute pain (simulating wound pain: this installation will apply monophasic, rectangular electrical pulses of 0.5ms duration with alternating polarity at 2 Hz frequency. The current will be increased to target a pain rating of 6 of 10 on the NRS (0 = no pain, 10 = worst imaginable pain). Three further adjustments in current will be made every 5 minutes for the next 15 minutes to compensate for habituation. This final current will be kept constant until the end of the particular experiment). In Part 1 duration of OLP analgesia will be examined, and onset and size of the effect will be reevaluated. In Part 2 of this study outcomes between subjects receiving one OLP injection, subjects receiving one repetition of the injection on a fixed time point and subjects receiving one repetition of the injection on-demand will be evaluated
Detailed description
Pain is highly prevalent in hospital settings. Standard systemic treatment for acute pain consists mainly of basic analgesia. The use of these drugs is often restricted due to their contraindications. Placebo is used nowadays to describe sham treatments and "inert" substances like sugar pills and saline injections. Placebos are proven to elicit clinically significant effects in various conditions, including pain. Ethical concerns about the use of deceptive placebos have prevented their implementation in clinical practice. A possibility to address this issue would be to prescribe placebos openly, that means, without deception. This randomized crossover study evaluates the efficacy of open-label placebo (OLP) in acute pain. Subjective pain ratings and areas of hyperalgesia and allodynia will be measured in a well-established experimental pain model (intradermal electrical stimulation model evoking pain: this installation will apply monophasic, rectangular electrical pulses of 0.5ms duration with alternating polarity at 2 Hz frequency. The current will be increased to target a pain rating of 6 of 10 on the NRS (0 = no pain, 10 = worst imaginable pain). Three further adjustments in current will be made every 5 minutes for the next 15 minutes to compensate for habituation. This final current will be kept constant until the end of the particular experiment) and analgesia elicited by OLP injections will be investigated.
In Part 1 duration of OLP analgesia will be examined, and onset and size of the effect will be reevaluated.
In Part 2 of this study outcomes between subjects receiving one OLP injection, subjects receiving one repetition of the injection on a fixed time point and subjects receiving one repetition of the injection on-demand will be evaluated (which leaves the last group a choice over when they would like to have the placebo "booster").
Interventions
- Procedure OLP-injection
Open-label placebo injections without any active ingredient (5 ml 0.9% saline). All participants will be informed that the administered injections are placebo infusions. - Other Scripted Evidence-based treatment rationale
As a second component the intervention will consist of an evidence-based treatment rationale, which will be delivered to patients receiving the intervention prior to the OLP-injections, explaining placebo analgesia in pain in general and specifically in OLP. In the context of OLP treatments this rationale is important in order to create a mental state of positive expectations. - Other Experimental model of acute pain
Experimental model of acute pain (simulating wound pain: this installation will apply monophasic, rectangular electrical pulses of 0.5ms duration with alternating polarity at 2 Hz frequency. The current will be increased to target a pain rating of 6 of 10 on the NRS (0 = no pain, 10 = worst imaginable pain). Three further adjustments in current will be made every 5 minutes for the next 15 minutes to compensate for habituation. This final current will be kept constant until the end of the particu
Primary outcome measures
- Part 1: Change in Area under the Pain Curve (AUPC) [Time frame: During three hours after administering an OLP]
- Part 2: Change in Area under the Pain Curve (AUPC) [Time frame: During three hours after administering an OLP]
Secondary outcome measures (3)
- Part 1 and 2: Change in subjective pain ratings on each measurement point using the numeric rating scale (NRS) [Time frame: Up to 200 minutes after electrical pain stimulation]
- Part 1 and 2: Change in Area under the Curve (AUC) of area of hyperalgesia [Time frame: Up to 200 minutes after electrical pain stimulation]
- Part 1 and 2: Change in Area under the Curve (AUC) of area of allodynia [Time frame: Up to 200 minutes after electrical pain stimulation]
Eligibility criteria
Inclusion criteria
- Healthy volunteers (ASA Class I or II), aged 18 to 65 years
- BMI between 18 and 25kg/m2
- Able to understand the study and the NRS
- Able to give informed consent
Exclusion criteria
- Participation in a previous open-label placebo study; for Part 2, this includes Part 1 of this study
- Regular intake of medications or drugs potentially interfering with pain sensation (analgesics, opioids, antihistamines, calcium and potassium channel blockers, serotonin/ noradrenaline reuptake inhibitors, corticosteroids)
- Neuropathy
- Chronic pain
- Neuromuscular disease
- Dermatological disease (i.e. Atopic Dermatitis)
- Psychiatric disease
- Pregnancy / Lactation
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Allocation
- Randomized
- Model
- Crossover
- Masking
- Single blind
- Primary purpose
- Other
Study locations
Switzerland · 1 center
- University Hospital of Basel (USB); Department of Anaesthesiology — Basel
Publications
- de Leeuw M, Laager M, Gaab J, Ruppen W, Schneider T. Boosting open-label placebo effects in acute induced pain in healthy adults (BOLPAP-study): study protocol of a randomized controlled trial. Front Med (Lausanne). 2024 Feb 14;11:1238878. doi: 10.3389/fmed.2024.1238878. eCollection 2024. PMID 38420356
Identifiers
NCT: NCT05819476 · 2023-00296; am23Schneider