Cognitive effects of intramuscular ketamine and oral triazolam in healthy volunteers.
Lawrence P Carter, Bethea A Kleykamp, Roland R. Griffiths, Miriam Z Mintzer
Psychopharmacology March 1, 2013 DOI: 10.1007/s00213-012-2883-x (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Randomized controlled trial Double-blind Peer reviewed |
|---|---|
| Sample size | 20 |
| Population | Healthy volunteers |
| Interventions | Ketamine Triazolam |
| Dose | 0.2, 0.4 mg/kg i.m. for ketamine; 0.2, 0.4 mg/70 kg p.o. for triazolam |
| Topics | Ketamine Esketamine |
| Keywords | Cognitive impairment Memory impairment Cognitive dysfunction Mental decline Cognitive effects Cognitive impact Cognitive performance Psychomotor impairment Psychomotor coordination Attention Working memory Episodic memory Drug effects Pharmacological effects Medication impact Drug action Psychotropic effects Drug comparison Physiological effects Psychomotor effects Ketamine effects Ketamine research Triazolam effects Triazolam research Self-perception of impairment Drug awareness Cognitive awareness Subjective effects Perception of impact Metacognition Underestimation of impairment Clearer perception |
| Citations | 19 |
| Key findings | Ketamine produces less cognitive impairment than triazolam at doses that produce greater subjective effects, and does not produce the underestimation of cognitive impairment seen with triazolam. |
Abstract
Several studies have documented impairments in memory processes as a result of ketamine administration; however, few studies have compared the profile of cognitive effects of ketamine to other drugs. The aim of this study was to compare the cognitive effects of ketamine with those of triazolam in healthy volunteers. Doses of ketamine (0.2, 0.4 mg/kg intramuscular (i.m.)), triazolam (0.2, 0.4 mg/70 kg p.o.), and double-dummy placebos were administered to 20 volunteers under repeated measures, counterbalanced, double-blind conditions. Peak physiological, psychomotor, subjective, and cognitive effects were examined. Ketamine impaired balance when balance was assessed early in the task order, whereas triazolam impaired psychomotor coordination and divided attention irrespective of task order. Triazolam also tended to produce greater effects on working memory and episodic memory tasks than ketamine at doses that produced lower subjective effects and higher estimates of performance. Ketamine produces less cognitive impairment than triazolam at doses that produced greater subjective effects. Thus ketamine does not produce the underestimation of cognitive impairment typically seen with triazolam.
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 6
- Neurocognitive effects of six ketamine infusions and the association with antidepressant response in patients with unipolar and bipolar depression Journal of Psychopharmacology September 27, 2018
- The Altered States Database: Psychometric data from a systematic literature review. Scientific Data November 23, 2022
- The acute effects of psychoactive drugs on emotional episodic memory encoding, consolidation, and retrieval: A comprehensive review. Neuroscience & Biobehavioral Reviews July 1, 2023
- Acute cognitive effects of high doses of dextromethorphan relative to triazolam in humans. Drug and Alcohol Dependence March 1, 2013
- Update of the Altered States Database (ASDB): 2022-12-31 February 22, 2023
and 1 more in the library
Cites 8
- Human hallucinogen research: guidelines for safety. Journal of Psychopharmacology July 1, 2008
- Dose-Response Study of N,N-Dimethyltryptamine in Humans Archives of General Psychiatry February 1, 1994
- Psychedelic Effects of Ketamine in Healthy Volunteers Anesthesiology 1998
- Comparative and Interactive Human Psychopharmacologic Effects of Ketamine and Amphetamine Archives of General Psychiatry September 1, 2005
- Ketamine Disrupts Frontal and Hippocampal Contribution to Encoding and Retrieval of Episodic Memory: An fMRI Study Cerebral Cortex November 10, 2004
and 3 more in the library