The primary objective is to investigate whether exogenous oxytocin administration enhances the placebo effect of positive suggestions as measured by subjective pain intensity and itch ratings in response to validated pain (Cold Pressor Test) and…
ID
Source
Brief title
Condition
- Other condition
Synonym
Health condition
Het onderzoek wordt bij gezonde personen uitgevoerd. Het onderzoek kan voor nieuwe inzichten zorgen bij therapeutische interventies voor pijn en jeuk.
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The main study parameters are self-reported pain in response to the Cold
Pressor Test and self-reported itch in response to the histamine iontophoresis.
Secondary outcome
Secondary parameters are skin temperature, flare response, and wheal size in
response to the histamine iontophoresis, unpleasantness ratings in response to
the Cold Pressor Task. Furthermore, the possible influence of psychological
parameters on outcomes will be explored as well.
Background summary
Placebo effects have been demonstrated to decrease pain and itch by means
positive suggestions. It is of high clinical relevance to find ways to maximize
placebo effects in order to obtain the best therapeutic results. Oxytocin
administration may potentially enhance the placebo effect but few studies have
been performed in this important area with conflicting evidence for pain and no
studies for itch.
Study objective
The primary objective is to investigate whether exogenous oxytocin
administration enhances the placebo effect of positive suggestions as measured
by subjective pain intensity and itch ratings in response to validated pain
(Cold Pressor Test) and itch-inducing (histamine iontophoresis) tasks.
Secondary objectives are to investigate the effects of oxytocin administration
combined with specific positive verbal suggestions on:
* Pain unpleasantness ratings during the Cold Pressor Test
* Skin temperature, flare response, and wheal size in response to histamine
iontophoresis.
* Positive and negative affect
* Pain and itch expectations
Study design
A randomized placebo-controlled, study design will be used. Participants will
be randomly allocated to one of four groups: 1) oxytocin group with positive
suggestions, 2) oxytocin group without positive suggestions, 3) placebo group
with positive suggestions, 4) placebo group without positive suggestions.
Participants will perform a baseline Cold Pressor Test and their pain
sensitivity, pain sensitivity threshold, pain tolerance threshold, and
unpleasantness ratings will be measured. Subsequently, participants will be
administered oxytocin or placebo spray and participants in two groups (oxytocin
with suggestions group and placebo with suggestions group) will receive
positive verbal suggestions about analgesic and itch-relieving effects of
oxytocin. After a waiting period for the oxytocin to take effect, the second
Cold Pressor Test will be done and the same parameters will be measured. The
session will finish with transdermal histamine iontophoresis. Itch ratings,
wheal size, and skin temperature will be measured.
Intervention
In the oxytocin with suggestions and oxytocin without suggestions groups,
participants will receive a 24 IU dose of oxytocin via a nasal spray. In the
placebo groups, participants will receive a placebo spray. The placebo effect
will be induced by positive suggestions about analgesic and itch-relieving
properties of the spray.
Study burden and risks
Participants need to invest a total of 1,5 hours in the study. No adverse side
effects are expected in the current study.
Several studies have been conducted in humans with repeated doses up to 80 IU
of oxytocin without reporting adverse side effects. One time administration of
24 IU of oxytocin is considered to be a safe and effective dose. The Cold
Pressor Test has been used in numerous studies with a maximum immersion time of
5 minutes or more. In the current study participants may withdraw their hand
from the cold water any time they wish with the maximum immersion of 1 minutes.
The symptoms of transdermal histamine iontophoresis (local swelling, itch, and
flare) will disappear within several minutes to a maximum of 2 hours; it has
been used in numerous studies without adverse effects. All other measurements
are considered minimally invasive. Participants will receive a reimbursement of
12,50 euros for participation in this study.
Wassenaarseweg 52
Leiden 2333 AK
NL
Wassenaarseweg 52
Leiden 2333 AK
NL
Listed location countries
Age
Inclusion criteria
- Female between 18 and 35 years old
- Good understanding of written and spoken Dutch
Exclusion criteria
- Refusal to give written informed consent
- Pregnancy or breast feeding
- Conditions that might interfere with the participant's safety and/or the study protocol: severe somatic or psychological morbidity (e.g., heart and lung diseases, or DSM-IV psychiatric disorders, Raynaud*s phenomenon)
- Chronic or acute itch or pain complaints
- Current use of analgesics, anti-inflammatory drugs, antihistamines, antibiotics
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
In other registers
| Register | ID |
|---|---|
| CCMO | NL55922.058.15 |
| OMON | NL-OMON27820 |