Passively administered fluoxetine reaches the juvenile brain of FSL rats and reduces antioxidant defences, without altering serotonin turnover.

BACKGROUND: Fluoxetine is present in breast milk, yet it is unclear to what extent it, or its active metabolite, norfluoxetine, reaches the brain of the infant and what the effects of such exposure on neurobiological processes are. We therefore aimed to quantify the concentration of passively administered fluoxetine and norfluoxetine in the whole brains of exposed Flinders sensitive line (FSL) offspring and establish their influence on serotonergic function and redox status. METHODS: Adult FSL dams received fluoxetine (10 mg/kg/day), or placebo for fourteen days, beginning on postpartum day 04. Offspring were passively exposed to fluoxetine until postnatal day 18 and euthanized on postnatal day 22. Whole brain fluoxetine, norfluoxetine, serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA), and reduced (GSH) and oxidized glutathione (GSSG) concentrations were measured via liquid chromatography-mass spectrometry (LC-MS) analysis. RESULTS: Whole-brain serotonin and 5-hydroxyindoleacetic acid concentrations, and serotonin turnover (5-HIAA/5-HT) were comparable between strains. Treatment-naïve FSL rats had lower GSH and higher GSSG whole-brain concentrations, relative to FRL controls, and an overall decreased GSH/GSSG ratio. Passively administered fluoxetine resulted in undetectable whole-brain concentrations, while norfluoxetine averaged 41.28 ± 6.47 ng/g. Serotonin turnover of FSL rats was unaffected by passively administered fluoxetine, while redox status (GSH/GSSG) was decreased. CONCLUSION: Our findings confirm that passively administered fluoxetine reaches the infant brain in the form of norfluoxetine and may manipulate processes of oxidative stress regulation. Further studies into the long-term bio-behavioural effects are however needed to effectively inform breast feeding mothers on the safety of antidepressant-use.

The effect of SSRIs on unconditioned anxiety: a systematic review and meta-analysis of animal studies.

RATIONALE: Selective serotonin reuptake inhibitors (SSRIs) are the first choice of treatment for anxiety-like disorders. However, which aspects of anxiety are affected by SSRIs is not yet fully understood. OBJECTIVE: We aimed to systematically review the effect of six clinically effective SSRIs on four aspects of unconditioned anxiety: approach-avoidance behaviour (elevated plus maze), repetitive behaviour (marble burying), distress behaviour (ultrasonic vocalization), and activation of the autonomous nervous system (stress-induced hyperthermia). METHODS: We identified publications by searching Medline and Embase databases and assessed the risk of bias. A random effects meta-analysis was performed and moderator effects were analysed with Bayesian penalized meta-regression. RESULTS: Our search yielded 105 elevated plus maze, 63 marble burying, 11 ultrasonic vocalization, and 7 stress-induced hyperthermia articles. Meta-analysis suggested that SSRIs reduce anxiety-like behaviour in the elevated plus maze, marble burying and ultrasonic vocalization test and that effects are moderated by pre-existing stress conditions (elevated plus maze) and dose dependency (marble burying) but not by duration of treatment or type of SSRI. The reporting quality was low, publication bias was likely, and heterogeneity was high. CONCLUSION: SSRIs seem to reduce a broad range of unconditioned anxiety-associated behaviours. These results should be interpreted with caution due to a high risk of bias, likely occurrence of publication bias, substantial heterogeneity and limited moderator data availability. Our review demonstrates the importance of including bias assessments when interpreting meta-analysis results. We further recommend improving the reporting quality, the conduct of animal research, and the publication of all results regardless of significance.

Pharmacokinetics of Trazodone in Hispaniolan Parrots (Amazona ventralis).

The objective of this study was to establish the pharmacokinetics of a single oral dose of trazodone in the Hispaniolan Amazon parrot (Amazona ventralis). Trazodone is a selective serotonin antagonist and reuptake inhibitor used commonly in both human and veterinary medicine as an antidepressant behavioral modification medicine. A single oral dose of compounded trazodone hydrochloride solution (20 mg/mL) at 50 mg/kg was administered to a total of 7 healthy adult Hispaniolan Amazon parrots. The 7 healthy adult parrots ranged in age from 10 to 15 years and weighed 228 to 323g. Blood was collected at baseline (2 weeks before study) and at 1, 2, 4, 6, 10, and 14 hours post-drug administration. Plasma concentrations of both trazodone and its active metabolite m-chlorophenylpiperazine (mCPP) were measured via liquid chromatography tandem mass spectrometry. Noncompartmental pharmacokinetic analysis was completed. The half-life (t1/2) ± SD of trazodone for the Hispaniolan parrots was 1.89 ± 0.49 hours, and the t1/2 ± SD of mCPP metabolite was 1.9 ± 0.55 hours. Maximum serum drug concentrations, or Cmax (ng/mL), were 738.3 ± 285.3 for trazodone. Times to achieve Cmax (hours) for trazadone and the mCPP metabolite were 1 hour and 2 hours postdosing, respectively. While this study did not establish the behavioral effects of trazodone, no adverse side effects were observed throughout the 48-hour period following drug administration and blood collection. Our results indicate that the oral administration of a 50-mg/kg single dose of trazodone to Hispaniolan parrots may be considered a safe dose. Plasma concentrations are comparable to previously published values in humans, dogs, horses, and pigeons (Columba livia domestica) for up to 14 hours following dosing. This study indicates that further studies are needed to establish the pharmacodynamics and the efficacy of trazodone in the medical management of behavioral problems in psittacine species.

Impact of trazodone once-a-day on quality of life and functional recovery in adults with major depressive disorder: A prospective, observational study.

BACKGROUND: Health-related quality of life (HRQL) is an important goal for patients with major depressive disorder (MDD), but whether antidepressants improve HRQL in these patients is unclear. Here, we describe the real-world effects of trazodone once-a-day (TzOAD) and selective serotonin reuptake inhibitor (SSRI) treatments on HRQL and functioning in adults with MDD. METHODS: This 8-week prospective, observational, open-label, multicenter study was conducted in adults with moderate or severe MDD for whom TzOAD or SSRI were prescribed as monotherapy. The primary outcome was life enjoyment and satisfaction assessed via the patient-reported Quality-of-Life Enjoyment and Satisfaction Questionnaire Short Form (Q-LES-Q-SF) from baseline to week 8. Secondary outcomes included change in Q-LES-Q-SF from baseline to weeks 1 and 2; severity of depressive symptoms using the Montgomery Åsberg Depression Rating Scale (MADRS) and sleep disturbance via the PROMIS SF-SD 8b questionnaire at weeks 1, 2, and 8; and overall functioning via the Sheehan Disability Scale (SDS), hedonic capacity using the Snaith-Hamilton Pleasure Scale (SHAPS), and cognitive dysfunction using the Perceived Deficits Questionnaire (PDQ-5) at baseline and week 8. RESULTS: The study included 208 adults with MDD (mean [SD] age = 50.2 [14.3] years; 68.6% female; 98.4% White). Life enjoyment and satisfaction improved from baseline to week 8 for both treatment groups: Q-LES-Q-SF mean (SD) scores were 27.5 (20.4) for the SSRI group and 39.0 (22.1) for the TzOAD group. Depressive symptoms and sleep disturbances also reduced from baseline to week 8: MADRS (SSRI, -15.7 [8.3]; TzOAD, -21.0 [9.8]); PROMIS SF-SD 8b (SSRI, -9.9 [12.6]; TzOAD, -22.0 [12.6]). Mean change scores in Q-LES-Q-SF, MADRS, and PROMIS SF-SD 8b improved as early as week 1 in both groups. Mean scores also improved from baseline to week 8 on SDS (SSRI, -9.2 [7.4]; TzOAD, -14.3 [7.5]), SHAPS (SSRI, -6.6 [4.3]; TzOAD, -8.3 [4.4]), and PDQ-5 (SSRI, -5.8 [4.5]; TzOAD, -7.7 [5.0]). CONCLUSIONS: In adults with MDD who received TzOAD or SSRIs, overall and individual HQRL domains improved rapidly and in parallel with improvements in depressive symptoms, with a slightly greater improvement observed in the TzOAD group.

Acute clomipramine exposure elicits dose-dependent surfacing behavior in adult zebrafish (Danio rerio).

Chronic treatment with clomipramine, a tricyclic antidepressant drug, reduces symptoms of obsessive-compulsive disorder (OCD) and can influence the activity of the hypothalamic-pituitary-adrenal axis. However, little is known regarding the effects of acute clomipramine on the immediate expression of stress responses. Serotonergic drugs can elicit surfacing, a behavioral profile potentially related to toxicity in fish, although surfacing has not yet been observed after clomipramine exposure. The present study investigated the impact of acute exposure to clomipramine on basal and stress-induced behaviors in the novel tank test and cortisol levels in mixed-sex, wild-type, adult zebrafish (Danio rerio). The findings show clomipramine-exposed groups (regardless of stress exposure) spent much more time in the top of the novel tank and had significantly less overall motor activity in the behavioral task compared to the fish not exposed to the drug. Then, the dose-dependent effects of acute clomipramine on activity in the surface of the novel tank (top third of the top half) were investigated further. Clomipramine dose-dependently increased surface-dwelling and elicited a dose-dependent hypoactivity in overall motor behavior. There were no statistically significant differences in whole-body cortisol levels in either experiment. Like other serotonin-acting drugs, clomipramine strongly elicited surface-dwelling and depressed motor behavior in adult zebrafish. Additional testing is needed to elucidate whether surfacing represents a toxic state and how serotonin regulates surfacing.

Sequenced Treatment Effectiveness for Posttraumatic Stress (STEPS) Trial: A protocol for a pragmatic comparative effectiveness trial with baseline results.

BACKGROUND: There have only been two efficacy trials reporting a head-to-head comparison of medications and psychotherapy for PTSD, and neither was conducted in primary care. Therefore, this protocol paper describes a pragmatic trial that compares outcomes of primary care patients randomized to initially receive a brief trauma-focused psychotherapy or a choice of three antidepressants. In addition, because there are few trials examining the effectiveness of subsequent treatments for patients not responding to the initial treatment, this pragmatic trial also compares the outcomes of those switching or augmenting treatments. METHOD: Patients screening positive for PTSD (n = 700) were recruited from the primary care clinics of 7 Federally Qualified Health Centers (FQHC) and 8 Department of Veterans Affairs (VA) Medical Centers and randomized in the ratio 1:1:2 to one of three treatment sequences: 1) selective serotonin reuptake inhibitor (SSRI) followed by augmentation with Written Exposure Therapy (WET), 2) SSRI followed by a switch to serotonin-norepinephrine reuptake inhibitor (SNRI), or 3) WET followed by a switch to SSRI. Participants complete surveys at baseline, 4 months, and 8 months. The primary outcome is PTSD symptom severity as measured by the PTSD Checklist (PCL-5). RESULTS: Average PCL-5 scores (M = 52.8, SD = 11.1) indicated considerable severity. The most common bothersome traumatic event for VA enrollees was combat (47.8%), and for FQHC enrollees was other (28.2%), followed by sexual assault (23.4%), and child abuse (19.8%). Only 22.4% were taking an antidepressant at baseline. CONCLUSION: Results will help healthcare systems and clinicians make decisions about which treatments to offer to patients.

Antidepressant prescription patterns and polypharmacy in outpatient psychiatry: a cross-sectional study.

Background and aim: Prescription patterns of antidepressants have changed over the years with a shift towards newer antidepressants with better tolerability and safety. Polypharmacy is common in psychiatry settings. The study aimed to evaluate the antidepressant drug prescription pattern and polypharmacy in a psychiatry outpatient setting. Investigations: This prospective observational study was conducted in a psychiatric outpatient clinic. The medication use data of eligible patients were collected. In addition, the rationale of antidepressant medication prescription, the defined daily dosage (DDD), the prescribed daily dose (PDD), and the PDD to DDD ratio were assessed. The assessment of prescription polypharmacy was conducted utilizing the framework provided by the National Association of State Mental Health Program Directors. Results: Data from 131 patients was analyzed. Major depressive disorder (32.8%) was the most common disorder for which antidepressants were prescribed. The majority, 91 (69.4%), received monotherapy. Selective serotonin reuptake inhibitors were the most frequently prescribed drugs in 69 (52.7%). Mirtazapine was the most frequently 32(24.4%) prescribed drug. Escitalopram and mirtazapine were the most commonly prescribed combination therapy (4.6%). Antipsychotic medications (37.4%) were the most widely co-prescribed medications, along with antidepressants. The PDD to DDD ratio was less than 1 for mirtazapine and imipramine; they were ≥1 for others. Psychiatric polypharmacy was documented in 87.1% of prescriptions. The total polypharmacy was not significantly (p>0.05) associated with demographic, illness, and treatment-related variables. Conclusion: Selective serotonin reuptake inhibitors were the most commonly prescribed antidepressants, monotherapy, and combination therapy. A substantial amount of patients received concomitant administration of antidepressants or psychotropic drugs, warranting careful monitoring.

A systematic review and meta-analysis, investigating dose and time of fluvoxamine treatment efficacy for COVID-19 clinical deterioration, death, and Long-COVID complications.

There have been 774,075,242 cases of COVID-19 and 7,012,986 deaths worldwide as of January 2024. In the early stages of the pandemic, there was an urgent need to reduce the severity of the disease and prevent the need for hospitalization to avoid stress on healthcare systems worldwide. The repurposing of drugs to prevent clinical deterioration of COVID-19 patients was trialed in many studies using many different drugs. Fluvoxamine (an SSRI and sigma-1 receptor agonist) was initially identified to potentially provide beneficial effects in COVID-19-infected patients, preventing clinical deterioration and the need for hospitalization. Fourteen clinical studies have been carried out to date, with seven of those being randomized placebo-controlled studies. This systematic review and meta-analysis covers the literature from the outbreak of SARS-CoV-2 in late 2019 until January 2024. Search terms related to fluvoxamine, such as its trade names and chemical names, along with words related to COVID-19, such as SARS-CoV-2 and coronavirus, were used in literature databases including PubMed, Google Scholar, Scopus, and the ClinicalTrials.gov database from NIH, to identify the trials used in the subsequent analysis. Clinical deterioration and death data were extracted from these studies where available and used in the meta-analysis. A total of 7153 patients were studied across 14 studies (both open-label and double-blind placebo-controlled). 681 out of 3553 (19.17%) in the standard care group and 255 out of 3600 (7.08%) in the fluvoxamine-treated group experienced clinical deterioration. The estimated average log odds ratio was 1.087 (95% CI 0.200 to 1.973), which differed significantly from zero (z = 2.402, p = 0.016). The seven placebo-controlled studies resulted in a log odds ratio of 0.359 (95% CI 0.1111 to 0.5294), which differed significantly from zero (z = 3.103, p = 0.002). The results of this study identified fluvoxamine as effective in preventing clinical deterioration, and subgrouping analysis suggests that earlier treatment with a dose of 200 mg or above provides the best outcomes. We hope the outcomes of this study can help design future studies into respiratory viral infections and potentially improve clinical outcomes.

Rationale and design for a pragmatic randomized trial to assess gene-based prescribing for SSRIs in the treatment of depression.

Specific selective serotonin reuptake inhibitors (SSRIs) metabolism is strongly influenced by two pharmacogenes, CYP2D6 and CYP2C19. However, the effectiveness of prospectively using pharmacogenetic variants to select or dose SSRIs for depression is uncertain in routine clinical practice. The objective of this prospective, multicenter, pragmatic randomized controlled trial is to determine the effectiveness of genotype-guided selection and dosing of antidepressants on control of depression in participants who are 8 years or older with ≥3 months of depressive symptoms who require new or revised therapy. Those randomized to the intervention arm undergo pharmacogenetic testing at baseline and receive a pharmacy consult and/or automated clinical decision support intervention based on an actionable phenotype, while those randomized to the control arm have pharmacogenetic testing at the end of 6-months. In both groups, depression and drug tolerability outcomes are assessed at baseline, 1 month, 3 months (primary), and 6 months. The primary end point is defined by change in Patient-Reported Outcomes Measurement Information System (PROMIS) Depression score assessed at 3 months versus baseline. Secondary end points include change inpatient health questionnaire (PHQ-8) measure of depression severity, remission rates defined by PROMIS score < 16, medication adherence, and medication side effects. The primary analysis will compare the PROMIS score difference between trial arms among those with an actionable CYP2D6 or CYP2C19 genetic result or a CYP2D6 drug-drug interaction. The trial has completed accrual of 1461 participants, of which 562 were found to have an actionable phenotype to date, and follow-up will be complete in April of 2024.

The impact of chronic fluoxetine treatment in adolescence or adulthood on context fear memory and perineuronal nets.

Selective serotonin reuptake inhibitors, such as fluoxetine (Prozac), are commonly prescribed pharmacotherapies for anxiety. Fluoxetine may be a useful adjunct because it can reduce the expression of learned fear in adult rodents. This effect is associated with altered expression of perineuronal nets (PNNs) in the amygdala and hippocampus, two brain regions that regulate fear. However, it is unknown whether fluoxetine has similar effects in adolescents. Here, we investigated the effect of fluoxetine exposure during adolescence or adulthood on context fear memory and PNNs in the basolateral amygdala (BLA), the CA1 subregion of the hippocampus, and the medial prefrontal cortex in rats. Fluoxetine impaired context fear memory in adults but not in adolescents. Further, fluoxetine increased the number of parvalbumin (PV)-expressing neurons surrounded by a PNN in the BLA and CA1, but not in the medial prefrontal cortex, at both ages. Contrary to previous reports, fluoxetine did not shift the percentage of PNNs toward non-PV cells in either the BLA or CA1 in the adults, or adolescents. These findings demonstrate that fluoxetine differentially affects fear memory in adolescent and adult rats but does not appear to have age-specific effects on PNNs.

Safety and Efficacy of Levomilnacipran Extended Release in Pediatric Patients Aged 7-17 Years with Major Depressive Disorder: Results of Two Phase 3, Randomized, Double-Blind Studies.

Objective: Major depressive disorder (MDD) presents a significant psychosocial burden, and there is an unmet need for additional treatment options in pediatric patients. Here, we report the results of two phase 3 multicenter, randomized, double-blind, placebo- and active-controlled, parallel-group studies evaluating the efficacy and safety of levomilnacipran extended release in children and adolescents with MDD. Methods: In the first study, LVM-MD-11, patients aged 12-17 years received daily doses of levomilnacipran 40 mg (n = 134), levomilnacipran 80 mg (n = 138), fluoxetine 20 mg (n = 134), or placebo (n = 141). In the second study, LVM-MD-14, patients aged 7-17 years received levomilnacipran 40 to 80 mg (n = 166), fluoxetine 20 mg (n = 166), or placebo (n = 160) daily. Primary and secondary efficacy endpoints were changes in Children's Depression Rating Scale-Revised (CDRS-R) total score and Clinical Global Impressions-Severity (CGI-S) score, respectively. Results: In LVM-MD-11, there were no significant differences in change in CDRS-R total score between patients treated daily with placebo (least squares mean [LSM] change in CDRS-R total score -22.9) versus levomilnacipran 40 mg (-23.3; p = 0.8035) or 80 mg (-22.6; p = 0.8681). Similarly, in LVM-MD-14, there were no significant differences in LSM change in CDRS-R total score with placebo (-21.3) versus levomilnacipran 40 to 80 mg daily (-23.0; p = 0.2215). There were also no significant differences between the fluoxetine and placebo groups in either study for changes in CDRS-R total score. Changes in CGI-S score were not significant between placebo and levomilnacipran 40 to 80 mg daily or between placebo and fluoxetine. Levomilnacipran was generally well tolerated. Conclusions: The high placebo response in this study prevented the detection of an effect of levomilnacipran in children and adolescents. Clinical Trial Registration numbers: NCT02431806 and NCT03569475.

Off-label higher doses of serotonin reuptake inhibitors in the treatment of obsessive-compulsive disorder: Safety and tolerability.

OBJECTIVE: To examine the long-term safety and tolerability of off-label high-dose serotonin reuptake inhibitors (OLHD-SRIs) in the treatment of obsessive-compulsive disorder (OCD). METHODS: A retrospective longitudinal study was performed on 105 randomly selected outpatients diagnosed with OCD and were treated with OLHD-SRIs for at least 6 months. Patients received sertraline >200 mg/day, escitalopram >20 mg/day, fluvoxamine >300 mg/day, and fluoxetine >60 mg/day, combined with exposure and response prevention therapy. Patients were divided into three dosing groups: sertraline equivalent dose (SED) ≤ 200 mg/day (n = 26, 24.7%), 201-400 mg/day (n = 51, 48.5%) and 401-650 mg/day (n = 28, 26.6%). Safety and tolerability were assessed with an electrocardiogram, blood biochemistry, complete blood count, and side-effects monitoring. RESULTS: SED ranged from 100 to 650 mg/day and the mean duration of OLHD-SRI treatment was 20.8 months. The most common side-effects reported were sexual dysfunction (n = 36, 34%), weight gain (n = 28, 27%), sedation (n = 27, 26%), hyperhidrosis (n = 20, 19%), and tremor (n = 11, 10%). Abnormal ECG was documented in one patient, and another patient experienced a first-time seizure, whereas elevated liver enzymes were seen in 4.8% of the sample (n = 5). None of the patients had serotonin syndrome or drug-induced liver injury. Side-effects did not differ among the three dosing groups. CONCLUSION: OLHD-SRIs appear to be safe and well tolerated in OCD patients in SED ≤ 650 mg/day doses and the side-effects did not differ between the three dosing groups.

Psychopharmacological treatment in patients planned for hip or knee replacement.

Psychopharmacological treatment may be an independent risk factor for increased length of stay and readmission after hip and knee replacement. Thus, temporary perioperative discontinuation may be beneficial. However, little is known regarding the treatments, and not all are feasible to discontinue. Therefore, the aim of this study was to describe the treatments in terms of type, dose, duration, indication and initiating physician to assess the feasibility of temporary perioperative discontinuation. We included 482 patients planned for hip or knee replacement in psychopharmacological treatment for psychiatric disorders from 2021 to 2023 at five orthopaedic departments in Denmark. Most patients were treated with antidepressants (89%); most frequently, either selective serotonin reuptake inhibitors (SSRIs; 48%) or serotonin-norepinephrine reuptake inhibitors (SNRIs; 21%). The majority received monotherapy (70%); most frequently, an SSRI (36%) or an SNRI (12%). Most antidepressants were initiated by general practitioners (71%), and the treatments had lasted for more than a year (87%). The doses of SSRIs/SNRIs were moderate, and the most frequent indication for antidepressants was depression (77%). These results imply that temporary perioperative SSRI/SNRI discontinuation may be feasible in hip and knee replacement patients and support a future randomized controlled trial investigating the potential benefits of temporary discontinuation.

The 5-HT7 receptor antagonist SB 269970 ameliorates maternal fluoxetine exposure-induced impairment of synaptic plasticity in the prefrontal cortex of the offspring female mice.

The use of a selective serotonin reuptake inhibitor fluoxetine in depression during pregnancy and the postpartum period might increase the risk of affective disorders and cognitive symptoms in progeny. In animal models, maternal exposure to fluoxetine throughout gestation and lactation negatively affects the behavior of the offspring. Little is known about the effects of maternal fluoxetine on synaptic transmission and plasticity in the offspring cerebral cortex. During pregnancy and lactation C57BL/6J mouse dams received fluoxetine (7.5 mg/kg/day) with drinking water. Female offspring mice received intraperitoneal injections of the selective 5-HT7 receptor antagonist SB 269970 (2.5 mg/kg) for 7 days. Whole-cell and field potential electrophysiological recordings were performed in the medial prefrontal cortex (mPFC) ex vivo brain slices. Perinatal exposure to fluoxetine resulted in decreased field potentials and impaired long-term potentiation (LTP) in layer II/III of the mPFC of female young adult offspring. Neither the intrinsic excitability nor spontaneous excitatory postsynaptic currents were altered in layer II/III mPFC pyramidal neurons. In mPFC slices obtained from fluoxetine-treated mice that were administered SB 269970 both field potentials and LTP magnitude were restored and did not differ from controls. Treatment of fluoxetine-exposed mice with a selective 5-HT7 receptor antagonist, SB 269970, normalizes synaptic transmission and restores the potential for plasticity in the mPFC of mice exposed in utero and postnatally to fluoxetine.

Content analysis of Reddit posts about coadministration of selective serotonin reuptake inhibitors and psilocybin mushrooms.

RATIONALE: Treatments with the serotonergic psychedelic psilocybin are being investigated for multiple neuropsychiatric disorders. Because many patients with these disorders use selective serotonin reuptake inhibitors (SSRIs), understanding interactions between psilocybin and SSRIs is critical for evaluating the safety, efficacy, and scalability of psilocybin-based treatments. Current knowledge about these interactions is limited, as most clinical psilocybin research has prohibited concomittant SSRI use. OBJECTIVES: We aimed to explore potential interactions between psilocybin and SSRIs by characterizing peoples' real-world experiences using psilocybin mushrooms and SSRIs together. METHODS: We conducted a systematic search of Reddit for posts describing psilocybin mushroom and SSRI coadministration. We identified 443 eligible posts and applied qualitative content analysis to each. RESULTS: 8% of posts reported negative physical or psychological effects resulting from coadministration. These included 13 reports that may reflect serotonin toxicity, and 1 concerning for a psychotic/manic episode. 54% of posts described reduced intensity of the acute psilocybin experience, but 39% reported unchanged intensity with SSRI coadministration. CONCLUSIONS: Psilocybin's interactions with SSRIs are likely complex and may depend on multiple factors. Prospective studies are needed to evaluate whether psilocybin treatments are reliably safe and effective in the setting of SSRI use.

Efficacy and safety of aticaprant, a kappa receptor antagonist, adjunctive to oral SSRI/SNRI antidepressant in major depressive disorder: results of a phase 2 randomized, double-blind, placebo-controlled study.

This was a double-blind, randomized, phase 2 study of adults (18-64 years) with DSM-5 diagnosis of major depressive disorder (MDD), with moderate-to-severe episode severity (Montgomery-Åsberg Depression Rating Scale [MADRS] ≥25) despite an adequate course with ongoing antidepressant for ≥6 weeks to ≤12 months. Following a double-blind placebo lead-in period (up to 3 weeks), participants were randomized to receive once daily aticaprant 10 mg or continue placebo, added to their ongoing treatment, for 6 weeks. Of 184 participants enrolled, 169 were included in safety analyses (aticaprant n = 85, placebo n = 84) and 166 in full intent-to-treat (fITT) efficacy analyses; 121 placebo lead-in non-responders (<30% reduction in MADRS total score) in fITT were included in enriched ITT (eITT) analyses. Improvement (least squares mean difference [upper limit 1-sided 80% CI] versus placebo) in MADRS total score at week 6 for aticaprant was significant versus placebo (eITT: -2.1 [-1.09], 1-sided p = 0.044; effect size (ES) 0.23; fITT -3.1 [2.21], 1-sided p = 0.002; ES 0.36). The between-group difference was larger among participants with Snaith-Hamilton Pleasure Scale (SHAPS) score greater/equal to versus less than baseline median SHAPS. The most common treatment-emergent adverse events reported for aticaprant (versus placebo) were headache (11.8% versus 7.1%), diarrhea (8.2% versus 2.4%), nasopharyngitis (5.9% versus 2.4%), and pruritus (5.9% versus 0%). One participant (1.2%) in each arm discontinued treatment due to an adverse event. In this study of participants with MDD and inadequate response to SSRI/SNRI, adjunctive treatment with aticaprant significantly reduced depressive symptoms versus placebo, without resulting in significant safety signals, supporting further investigation in larger trials.

Neurochemical mechanisms underlying serotonergic modulation of neuroplasticity in humans.

BACKGROUND: Studies in animals and humans have shown that cortical neuroplasticity can be modulated by increasing serotonin levels by administering selective serotonin reuptake inhibitors (SSRI). However, little is known about the mechanistic background, especially the contribution of intracortical inhibition and facilitation, which depend on gamma-aminobutyric acid (GABA) and glutamate. OBJECTIVE: We aimed to explore the relevance of drivers of plasticity (glutamate- and GABA-dependent processes) for the effects of serotonin enhancement on tDCS-induced plasticity in healthy humans. METHODS: A crossover, partially double-blinded, randomized, and sham-controlled study was conducted in 21 healthy right-handed individuals. In each of the 7 sessions, plasticity was induced via transcranial direct current stimulation (tDCS). Anodal, cathodal, and sham tDCS were applied to the left motor cortex under SSRI (20 mg/40 mg citalopram) or placebo. Short-interval cortical inhibition (SICI) and intracortical facilitation (ICF) were monitored by paired-pulse transcranial magnetic stimulation for 5-6 h after intervention. RESULTS: Under placebo, anodal tDCS-induced LTP-like plasticity decreased SICI and increased ICF. In contrast, cathodal tDCS-elicited LTD-like plasticity induced the opposite effect. Under 20 mg and 40 mg citalopram, anodal tDCS did not affect SICI largely, while ICF was enhanced and prolonged. For cathodal tDCS, citalopram converted the increase of SICI and decrease of ICF into antagonistic effects, and this effect was dosage-dependent since it lasted longer under 40 mg when compared to 20 mg. CONCLUSION: We speculate that the main effects of acute serotonergic enhancement on tDCS-induced plasticity, the increase and prolongation of LTP-like plasticity effects, involves mainly the glutamatergic system.

Perspectives on the impact of vortioxetine on the treatment armamentarium of major depressive disorder.

INTRODUCTION: Major Depressive Disorder (MDD) is a mental health issue that significantly affects patients' quality of life and functioning. Despite available treatments, many patients continue to suffer due to incomplete symptom resolution and side effects. AREAS COVERED: This manuscript examines Vortioxetine's role in Major Depressive Disorder (MDD) treatment, highlighting its potential to reshape therapeutic strategies due to its unique Multimodal action and proven broad-spectrum efficacy in multiple depressive domains. A detailed examination of Vortioxetine's pharmacological aspects, including indications, dosage, pharmacodynamics, and pharmacokinetics, is provided, emphasizing its safety and effectiveness. The discussion extends to Vortioxetine's role in acute-phase treatment and maintenance of MDD and its profound impact on specialized depression domains. EXPERT OPINION: Vortioxetine is distinguished for its novel multimodal serotonin modulation mechanism, showcasing significant promise as an innovative treatment for MDD. Its efficacy, which is dose-dependent, along with a commendable tolerability profile, positions it as a potential leading option for initial treatment strategies. The discourse on dosage titration, particularly the strategy of initiating treatment at lower doses followed by gradual escalation, underscores the approach toward minimizing initial adverse effects while optimizing therapeutic outcomes, aligning with the principles of personalized medicine in psychiatric care.

Effects of discontinuation of serotonergic antidepressants prior to psilocybin therapy versus escitalopram for major depression.

BACKGROUND: There is growing evidence for the therapeutic effects of the psychedelic drug psilocybin for major depression. However, due to the lack of safety data on combining psilocybin with selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) and concerns that there may be a negative interaction on efficacy, participants enrolling in psychedelic trials are usually required to discontinue SNRI/SNRIs prior to enrolling. AIMS: Using data from a recent clinical trial examining the comparative efficacy the psychedelic drug psilocybin (P) combined with approximately 20 h of psychological support to a 6-week (daily) course of the SSRI escitalopram plus matched psychological support for major depressive disorder, we explored the effects of discontinuing SSRI/SNRIs prior to study enrolment on study outcomes. METHODS: Exploratory post hoc analyses using linear mixed effects model were performed to investigate the discontinuation effect on various validated depression symptom severity scales and well-being. The impact of SSRI/SNRIs discontinuation on the acute psychedelic experience was also explored. RESULTS/OUTCOMES: In the psilocybin group, there was a reduced treatment effect on all outcome measures for SSRI/SNRIs discontinuers compared with unmedicated patients at trial entry. However, no effects of discontinuation on measures of the acute psychedelic experience were found. CONCLUSION: Discontinuation of SSRI/SNRIs before psilocybin might diminish response to treatment; however, as we did not test SSRI/SNRI continuation in our trial, we cannot infer such causation. Moreover, the exploratory nature of the analyses makes them hypothesis generating, and not confirmatory. A controlled trial of SSRI/SNRI discontinuation versus continuation prior to psilocybin is urgently required.