The Effect of Suggestion on Unpleasant Dreams Induced by Ketamine Administration
Soon Ho Cheong, Kun Moo Lee, Se Hun Lim, Kwang Rae Cho, Myoung Hun Kim, Myoung Jin Ko, Joo Cheol Shim, Min Kyung Oh, Yong Han Kim, Sang Eun Lee
Anesthesia & Analgesia February 25, 2011 DOI: 10.1213/ane.0b013e31820eeb0e (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Randomized controlled trial Peer reviewed |
|---|---|
| Sample size | 100 |
| Population | Patients receiving ketamine sedation for a procedure |
| Intervention | Ketamine |
| Measures | pleasantness/unpleasantness scale (grade 1 very unpleasant to grade 5 very pleasant) |
| Topics | Esketamine Ketamine |
| Citations | 29 |
| Key findings | Among patients who lost consciousness, a pre-sedation positive suggestion was associated with fewer unpleasant dreams (0% vs 8%) and more pleasant dreams (54% vs 22%) compared with no suggestion (P=0.01), but in the intent-to-treat population overall dream-mood frequencies were similar between groups. The authors suggest positive suggestion may help reduce recall of unpleasant dreaming with ketamine sedation. |
Abstract
The use of ketamine may be associated with the recall of unpleasant dreams after sedation. We hypothesized that a positive suggestion before sedation could reduce the incidence of ketamine-induced unpleasant dreams. To test this hypothesis, we randomized 100 patients receiving sedation with ketamine for their procedure into 2 groups with 1 group having an anesthesiologist provide a mood-elevating suggestion to the patient before ketamine administration (suggestion group), whereas in the control group no suggestion was provided. Patients were provided with a pleasantness/unpleasantness scale to rate "the overall mood of the dream" as very unpleasant (grade 1), quite unpleasant (grade 2), neither or mixed (grade 3), quite pleasant (grade 4), and very pleasant (grade 5). In those patients who lost consciousness, the frequencies of grades 1, 2, 3, 4, and 5 were 0%, 0%, 46%, 24%, and 30% in the suggestion group and were 6%, 2%, 70%, 12%, and 10%, respectively, in the control group (P=0.01). In the intent-to-treat population the overall frequency between groups was very similar. This study implies that when administering ketamine as part of a sedation regimen, positive suggestion may help reduce the recall of unpleasant dreaming.
Comparable studies
Other randomized controlled trials on ketamine, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Subanesthetic Effects of the Noncompetitive NMDA Antagonist, Ketamine, in Humans Healthy human subjects recruited from the community | 1994 | Randomized controlled trial | n = 19 |
| Antidepressant Efficacy of Ketamine in Treatment-Resistant Major Depression: A Two-Site Randomized Controlled Trial Patients with treatment-resistant major depression experiencing a major depressive episode | 2013 | Randomized controlled trial | n = 73 |
| Remifentanil-induced Postoperative Hyperalgesia and Its Prevention with Small-dose Ketamine Patients undergoing major abdominal surgery | 2005 | Randomized controlled trial | n = 75 |
| Efficacy of Intravenous Ketamine for Treatment of Chronic Posttraumatic Stress Disorder Patients with chronic PTSD related to a range of trauma exposures | 2014 | Randomized controlled trial | n = 41 |
| Ketamine-Induced Deficits in Auditory and Visual Context-Dependent Processing in Healthy Volunteers Healthy volunteers | 2000 | Single-blind placebo-controlled study | n = 20 |
Citations in the library
Cited by 10
- Culture, context, and ethics in the therapeutic use of hallucinogens: Psychedelics as active super-placebos? Transcultural Psychiatry October 1, 2022
- Are we really unconscious in "unconscious" states? Common assumptions revisited. Frontiers in Human Neuroscience 2022
- The Montreal model: an integrative biomedical-psychedelic approach to ketamine for severe treatment-resistant depression Frontiers in Psychiatry September 19, 2023
- Dreaming During Anesthesia and Sedation Anesthesia & Analgesia April 23, 2011
- Effect of Low-Dose Ketamine Infusion in the Intensive Care Unit on Postoperative Opioid Consumption and Traumatic Memories After Hospital Discharge: A Randomized Controlled Trial. Anesthesia & Analgesia February 5, 2025
and 5 more in the library
Cites 3
- The relationship of nightmare frequency and nightmare distress to well‐being Journal of Sleep Research May 26, 2004
- The incidence of unpleasant dreams after sub-anaesthetic ketamine. Psychopharmacology March 1, 2009
- Development of disturbing dreams during adolescence and their relation to anxiety symptoms. Sleep September 1, 2000