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Gilmar Gutierrez

Department of Psychiatry, Queen's University, Kingston, Ontario, Canada.

6 papers in the library · 64 citations · publishing 2023-2026

Papers

Efficacy and Safety of Four Psychedelic-Assisted Therapies for Adults with Symptoms of Depression, Anxiety, and Posttraumatic Stress Disorder: A Systematic Review and Meta-Analysis

Journal of Psychoactive Drugs November 15, 2023 Anees Bahji, Isis Lunsky, Gilmar Gutierrez et al. 21 citations

A systematic review and meta-analysis of 18 studies found that psychedelic-assisted therapies—psilocybin, LSD, MDMA, and ayahuasca—were well tolerated and produced large reductions in depression symptoms across various diagnoses. Psilocybin showed a large effect (standardized mean difference -1.92) and MDMA a moderate-to-large effect (standardized mean difference -0.71). However, the certainty of the evidence was low to very low due to small sample sizes, blinding issues, study heterogeneity, and publication bias. The results are promising but highlight the need for larger, more rigorous studies.

IN Esketamine and IV Ketamine: Results of a multi-site observational study assessing the effectiveness and tolerability of two novel therapies for treatment-resistant depression.

Psychiatry research October 1, 2024 Gilmar Gutierrez, Jennifer Swainson, Nisha Ravindran et al. 17 citations

Both intravenous ketamine and intranasal esketamine significantly reduce depressive symptoms and suicidal ideation in people with treatment-resistant major depressive disorder. In a multi-site observational study of 53 patients, those receiving IV ketamine (26 patients, average age 52.8) and those receiving IN esketamine (27 patients, average age 43.9) showed similar improvements in depression severity and suicidal thoughts. Side effects were mild and temporary, with no significant difference in risk between the two treatments. The findings suggest both therapies are effective and well tolerated for treatment-resistant depression.

IV low dose ketamine infusions for treatment resistant depression: Results from a five-year study at a free public clinic in an academic hospital.

Psychiatry research May 1, 2024 Gilmar Gutierrez, Melody J Y Kang, Gustavo Vazquez 12 citations

In patients with major depressive disorder and treatment-resistant depression, intravenous low-dose ketamine combined with standard care significantly reduced depressive symptoms and suicidal ideation over a five-year period. Of 71 outpatients, 54.93% responded to treatment, 78.26% experienced transient mild side effects, and 11.27% dropped out. Demographic variables did not affect treatment outcome or tolerability. The findings suggest that low-dose ketamine is an effective, fast-acting, and well-tolerated option for managing depressive symptoms and suicidal ideation in this population in real-world clinical settings.

Cognitive changes in patients with unipolar TRD treated with IV ketamine: A systematic review.

Progress in neuro-psychopharmacology & biological psychiatry December 20, 2024 Veronica Grasso, Gilmar Gutierrez, Najat Alzbeidi et al. 9 citations

Unipolar treatment-resistant depression is linked to cognitive impairment. A systematic review of fourteen studies found that intravenous ketamine treatment shows promise for improving neurocognitive function in these patients, including processing speed, working memory, verbal and visual memory, executive function, attention, emotional processing, and auditory verbal episodic memory. One study reported negative effects on verbal memory. The evidence had a low risk of bias, but limitations include small sample sizes, heterogeneity, and a predominantly female, Western, and Caucasian population, constraining generalizability. Further research is needed on long-term effects and confounders.

Abuse liability for esketamine in a cohort of patients undergoing an acute treatment course to manage treatment-resistant depression: a secondary analysis of an observational study in real-world clinical practicee.

Therapeutic advances in drug safety January 1, 2025 Gilmar Gutierrez, Gustavo Vazquez, Nisha Ravindran et al. 5 citations

Intranasal esketamine, used for treatment-resistant depression, does not appear to carry significant abuse liability during an acute course of treatment. In a secondary analysis of a multicenter observational study, 23 patients with major depressive disorder reported neutral liking and no cravings for esketamine after their first dosing session, and these measures did not increase over eight sessions. Neither age, sex, baseline depression severity, side effects, nor study site influenced liking or cravings. The findings align with existing literature suggesting that acute esketamine treatment is not associated with high drug liking or cravings, though larger studies are needed.

Ketamine and esketamine for the prevention of postpartum depression: A systematic review and network meta-analysis, with an integrated evidence synthesis.

Psychiatry research September 1, 2026 Isis Lunsky, Gilmar Gutierrez, Xena Wang et al.

Postpartum depression (PPD) is common and harmful if untreated, with few effective prevention strategies. Ketamine and esketamine are rapid-acting antidepressants showing promise for PPD. This review searched five databases for peer-reviewed randomized controlled trials, pilot studies, and observational studies examining ketamine or esketamine for PPD prevention during pregnancy or postpartum, for both cesarean and vaginal deliveries. A network meta-analysis and narrative synthesis were used. Thirty-six studies were identified; five included vaginal delivery, thirty included cesarean section, and one did not specify delivery mode. Results suggested that ketamine and esketamine were well tolerated and may reduce PPD risk. However, data quality was low to very low, so results should be interpreted cautiously. More high-quality studies are needed.