The Black Book of Psychotropic Dosing and Monitoring.

Introduction Since the last edition of the Black Book, several innovative agents have been approved or are poised to be approved in the coming year. These include novel antidepressants, the first muscarine agonist for the treatment of schizophrenia, the first psychedelic which may be approved for the treatment of PTSD (Post Traumatic Stress Disorder), and the first disease modifying drug for the treatment of Alzheimer's disease. Three new antidepressants have come to the market in the past 18 months. The first of those, Auvelity, the combination of bupropion and dextromethorphan, takes advantage of a pharmacokinetic and pharmacodynamic synergism between the two drugs.85 Dextromethorphan has several pharmacodynamic properties including actions on the NMDA receptor and the Sigma 1 receptor, adding to the indirect norepinephrine agonist properties of bupropion. How Dextromethorphan is rapidly metabolized via the CYP2D6 isoenzyme to dextrophan that may have mu opioid agonist properties. The combination with bupropion, a CYP2D6 inhibitor, inhibits the metabolism of dextromethorphan allowing for more consistent therapeutic levels. The combination of dextromethorphan 45 mg twice per day and bupropion SR 105 mg twice daily appears to be more effective than an equivalent dose of bupropion alone both in speeding up antidepressant response and achieving remission. However, it's not clear at this time how the combination would compare with a more typical dose of bupropion of 300-450 milligrams a day range. The phase III program for Auvelity, showed that the drug was well tolerated with the most common side effects being dizziness, headache, and dry mouth.86 Another novel antidepressant agent approved in 2023 is zuranolone (Zurzuvae). Zuranolone is an oral analog of IV brexanalone, and like brexanolone, was approved for the treatment of post-partum depression.83 The advantages of zuranolone over brexanalone are many. While brexanolone is a 60-hour intravenous infusion that must be administered in a health care facility, zuranolone is a once/day oral medication that is usually taken at home. Like brexanolone, and unlike most antidepressants, zuranolone has a short course of treatment, lasting just 14 days. Zuranolone's, as does brexanolone, is thought to act primarily as allosteric modulator of the GABA-a receptors. Despite only 14 days of treatment, zuranolone produced in depression in post-partum patients a clinically and significantly meaningful improvement at day 15 and continued to day 45 or 1 month past the end of treatment. Zuranolone is a schedule IV drug. The most common side effect in clinical trials was somnolence with 36% of participants reporting this side effect vs only 6% of those on placebo.84 Other common side effects included dizziness, diarrhea and fatigue. While the FDA declined to approve zuranolone as monotherapy or as an adjunctive treatment to standard antidepressants in major depression itself, there are positive studies in non-post-partum major depression albeit with smaller effect sizes and less consistent duration of activity. It is likely that zuranolone will continue to be studied in other depressive syndromes such as depression with anxious distress. The third "new" antidepressant approved late 2023 was gepirone (Exxua). Gepirone is not exactly a new or novel antidepressant and originally sought approval in the US about 20 years ago.88 There had been two positive studies of gepirone during the original NDA application but also a number of failed, negative, or non-informative studies as well. Thus, the FDA declined to originally approve the drug. However, failed and negative trials are common with antidepressants and after much internal debate, the FDA ultimately agreed to approve the drug based on the positive trials and a relatively favorable side effect profile. Gepirone, like buspirone, is a partial agonist of the 5HT1a receptor and a 5HT2 antagonist. As such, gepirone does not tend to be associated with sexual side effects, weight gain, or sedation. The most common side effects are dizziness, nausea, and insomnia which tend to improve in many patients over time. Second generation antipsychotics (SGAs) continue to be the only class of agents [other than esketamine (Spravato)] approved in adjunctive treatment of resistant major depression. In addition to olanzapine (combined with fluoxetine; Symbyax), aripiprazole (Abilify), quetiapine (Seroquel), brexpiprazole (Rexulti), cariprazine (Vraylar) became the latest SGA to be approved in 2022.90 Adjunctive cariprazine at 1.5 mg daily was significantly more effective than adjunctive placebo in patients with MDD who had failed to achieve an adequate response with an antidepressant alone after 6 weeks of treatment. Interestingly, a 3 mg dose of cariprazine was less consistently effective.91 The major advantage of cariprazine over some of the other approved adjunctive SGA's is easy dosing, with the starting 1.5 mg dose being the optimal therapeutic dose for most people, and a lower metabolic side effect burden with most subjects having limited or no weight gain in short term trials. The most common side effect were akathisia/restlessness, fatigue, and nausea. Lumateperone (Caplyta) is also has positive phase III data in the adjunctive treatment of major depression and is expective file for approval in late 2024. Another recent major development in psychopharmacology is the reemergence of psychedelics in the treatment of psychiatric disorders. The first of these is MDMA (phenethylamine 3,4-methylenedioxymethamphetamine) assisted psychotherapy for the treatment of PTSD. A New Drug Application (NDA) was accepted by the FDA for MDMA in the treatment of PTSD in late 2023.87 Because the drug is being fast tracked as a "breakthrough" treatment by the FDA, it was expected to see approval in the summer of 2024. The phase II and III data for MDMA assisted psychotherapy in the treatment of PTSD have been quite consistent and impressive. However, independent reviews have pointed to significant deficiencies in these studies including the bias introduced because of functional unblinding; virtually all patients in psychedelic studies can guess whether they got the active drug or placebo. The functional unblinding, the lack of standardization of adjunctive psychotherapy as well as the abuse potential of MDMA, may delay an FDA approval. The typical regimen in these trials included 3 preparatory psychotherapy sessions followed by once/month dosing sessions (lasting about 8 hours) and using doses of 120-160 mg in a split dose. There were typically 3 monthly dosing sessions, each followed by 3 integrative psychotherapy sessions to help subjects process and understand their experiences during the dosing sessions. In the most recent phase 3 trials, over 70% of subjects no longer met criteria for PTDS compared to 46% of those treated with psychotherapy and placebo alone.89 The only approved medications for treating PTSD are two SSRIs, paroxetine and sertraline. These drugs effect only some dimensions of PTSD with only 20-30% achieving a remission level response with these drugs. Thus, MDMA assisted psychotherapy appears to achieve much higher levels of remission and response than has been true for the SSRIs. Since MDMA is not taken continuously, side effects from MDMA tend to be short lived. Side effects have included muscle tightness, nausea, diminished appetite, excessive sweating, feeling cold and dizziness among others. Since MDMA is currently a schedule I drug, it is likely that a rigorous Risk Evaluation Mitigation (REMs) program will be put in place and a limited number of centers and clinicians will be designated to perform MDMA assisted psychotherapy for PTSD. In addition to MDMA, psilocybin-assisted psychotherapy is in phase 3 trials for treating resistant depression but unlikely to be available before late 2025 at the earliest. An argument can be made that there has not been a truly novel antipsychotic since the introduction of clozapine in the US in 1990. All first-generation antipsychotics have been dopamine 2 antagonists and second-generation drugs have involved some ratio of 5HT2 antagonism to D2 blockade. In 2023, the FDA accepted the application of xenomaline/tropsium (KarXT) which may become the first muscarinic M1M4 agonist approved for the treatment of schizophrenia.82,83 Tropsium is added as a muscarine antagonist to block the peripheral cholinergic effects of a muscarine agonist. Xenomaline/tropsium appears to be effective in treating both positive and negative symptoms of schizophrenia. In a phase 3 study of 407 patients with schizophrenia, xenomaline/tropsium at doses of xenomaline/50 mg/tropsium 20 mg twice daily up to 125 mg/30 mg twice daily was significantly more effective than placebo in treating both and negative symptoms over 5 weeks of treatment. As would be expected, the side effect profile of xenomaline/tropsium is very different that all currently available antipsychotics. There is no risk of EPS as it is not a dopamine antagonist, and xenomaline/tropsium is not associated with significant metabolic effects. The side effects are cholinergic in nature and include constipation, dry mouth, and nausea. A decision is expected in September of 2024. The year 2023 also saw the approval of the first disease modifying drug in the treatment of Alzheimer's disease, lecanemab (Lequembi). While acetylcholinesterase inhibitors and memantine have been available for decades, these drugs modestly improve cognition in Alzheimer's disease patients and do not alter the progressive course of the illness. Lecanemab is an IV monoclonal antibody that targets the removal of beta-amyloid in the brain as well proto-fibrils that are also known to be toxic to neuronal tissue. When given early in the course of the illness, patients treated with Lecanemab showed 27% less decline on some measures of cognition and function thandid patients treated with a placebo over 18 months (about 1 and a half years). It is not known whether treatment for longer than 18 months would show lesser or greater decline over time. However, there are simulation studies that suggest that Lecanemab may modestly reduce the number of patients who progress to severe Alzheimer's disease and require institutional care. The standard dose is 10 mg/kg given via IV over one hour every 2 weeks for 18 months. Lecanemab is typically administered in an infusion center so that side effects can be monitored. The most serious side effects of Lecanemab are amyloid related imaging abnormalities (ARIA) that are associated with brain edema and microhemorrhages. ARIA can occur in up to 15% of patients. More common side effects are headache and nausea. While it remains to be seen how useful these new agents will be in clinical practice, they do represent an approach to treating neuropsychiatric disorders that are a notable departure from the pharmacotherapy of the past half century. It seems likely that some patients who have not been able to respond to or tolerate traditional pharmacotherapy will find hope in these new medications.

In vitro biotransformation of 3-methylmethcathinone (3-MMC) through incubation with human liver microsomes and cytosol and application to in vivo samples.

Synthetic cathinones are the second largest group of new psychoactive substances (NPS) monitored by the European Monitoring Centre for Drugs and Drug Addiction. Although 3-methylmethcathinone (3-MMC, C11H15NO) is legally banned in many countries, it is readily available for purchase online and on the street. Due to the scarcity of information regarding the pharmacokinetic and toxicological profile of 3-MMC, understanding its biotransformation pathways is crucial in determining its potential toxicity in humans and in the development of analytical methods for screening of human matrices. To gain more insight, Phase I and Phase II in vitro biotransformation of 3-MMC was investigated using human liver microsomes and human liver cytosol. Suspect and non-target screening approaches were employed to identify metabolites. To confirm in vitro results in an in vivo setting, human matrices (i.e., plasma, urine, saliva and hair) positive for 3-MMC (n=31) were screened. In total three biotransformation products were identified in vitro: C11H15NO2 (a hydroxylated derivate), C11H17NO (a keto-reduced derivate) and C10H13NO (an N-desmethyl derivate). All three were confirmed as human metabolites in respectively 16 %, 52 % and 42 % of the analysed human samples. In total, 61 % of the analysed samples were positive for at least one of the three metabolites. Interestingly, three urine samples were positive for all three metabolites. The presence of 3-MMC in saliva and hair indicates its potential applicability in specific settings, e.g., roadside testing or chronic consumption analysis. To our knowledge, C11H17NO was not detected before in vivo. Although some of these metabolites have been previously suggested in vitro or in a single post mortem case report, a wide in vivo confirmation including the screening of four different human matrices was performed for the first time. These metabolites could serve as potential human biomarkers to monitor human 3-MMC consumption effectively.

3-CMC, 4-CMC, and 4-BMC Human Metabolic Profiling: New Major Pathways to Document Consumption of Methcathinone Analogues?

Synthetic cathinones represent one of the largest and most abused new psychoactive substance classes, and have been involved in numerous intoxications and fatalities worldwide. Methcathinone analogues like 3-methylmethcathinone (3-MMC), 3-chloromethcathinone (3-CMC), and 4-CMC currently constitute most of synthetic cathinone seizures in Europe. Documenting their consumption in clinical/forensic casework is therefore essential to tackle this trend. Targeting metabolite markers is a go-to to document consumption in analytical toxicology, and metabolite profiling is crucial to support investigations. We sought to identify 3-CMC, 4-CMC, and 4-bromomethcathinone (4-BMC) human metabolites. The substances were incubated with human hepatocytes; incubates were screened by liquid chromatography-high-resolution tandem mass spectrometry and data were mined with Compound Discoverer (Themo Scientific). 3-CMC-positive blood, urine, and oral fluid and 4-CMC-positive urine and saliva from clinical/forensic casework were analyzed. Analyses were supported by metabolite predictions with GLORYx freeware. Twelve, ten, and ten metabolites were identified for 3-CMC, 4-CMC, and 4-BMC, respectively, with similar transformations occurring for the three cathinones. Major reactions included ketoreduction and N-demethylation. Surprisingly, predominant metabolites were produced by combination of N-demethylation and ω-carboxylation (main metabolite in 3-CMC-positive urine), and combination of ß-ketoreduction, oxidative deamination, and O-glucuronidation (main metabolite in 4-CMC-positive urine). These latter metabolites were detected in negative-ionization mode only and their non-conjugated form was not detected after glucuronide hydrolysis; this metabolic pathway was never reported for any methcathinone analogue susceptible to undergo the same transformations. These results support the need for comprehensive screening strategies in metabolite identification studies, to avoid overlooking significant metabolites and major markers of consumption.

N-Ethylhexedrone: A very long and bad trip! A case series.

N-ethylhexedrone (NEH) is a new cathinone derivative with, currently, low toxicokinetic and toxicodynamic knowledge. We present three documented clinical cases of NEH intoxication with plasma and urine concentrations. A thorough search for metabolites was performed. The three patients were admitted to the emergency department, and two out of the three were hospitalized for an extended period. While recovering from the drug effects, 12-24 h after nasal intake of New Psychoactive Substance (NPS), the patients described the following disorders: anxiety, feelings of persecution, asthenia, anhedonia, abulia, psychomotor slowing and loss of consciousness. NEH was identified in all samples by liquid chromatography-high resolution mass spectrometry (LC-HRMS), and quantified by liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS). Quantitative analysis showed decreasing concentrations over time: for Case 1, from 97.2 (Day 1, D1) to 0.7 (Day 7, D7) µg/L for plasma, and from 724 (D1) to 0.5 (D7) µg/L for urine. NEH concentration of 7.9 µg/L was found in the plasma collected at admission for Case 2. For Case 3, concentrations ranging from 49 (D1) to 1.8 (D7) µg/L in plasma, and from 327.3 (Day 6, D6) to 116.8 (D7) µg/L in urine were found. NEH was no longer detected in the urine sample at Day 10. Elimination half-life was estimated at 19, and 28 hours in Patients 1 and 3, respectively. Four metabolites were identified in blood and urine: reduced NEH, dealkyl-NEH, reduced dealkyl-NEH and hydroxy-NEH. The cases presented highlight the long detectable lifetime of NEH. Characterization of the metabolites will allow better identification of the consumption of this drug. Serious adverse events can be observed after NEH consumption, as two out of the three patients required intubation and ventilation. A syndrome of inappropriate antidiuretic hormone secretion (SIADH) was also diagnosed. Two out of the three cases are notable because of the number of samples collected and because NEH was the only drug of abuse detected.

Interactions between grapefruit juice and psychotropic medications: an update of the literature and an original case series.

INTRODUCTION: There is a large body of preclinical data implicating that grapefruit juice (GJ) inhibits many CYP 450 isoforms. The potential of GJ-to-drug is of high relevance to clinical psychiatry, because a wide range of psychotropic medicines undergo CYP 450 metabolism and P-gp transport. AREAS COVERED: Relevant data were identified by searching the electronic databases up to February 2024. This work constitutes a summary of preclinical and clinical data on GJ impact on CYP 450 metabolism, P-glycoprotein, and organic anion-transporting polypeptides (OATPs), with focus on studies that assessed GJ-to-psychotropic drug interactions. Additionally, an unpublished case series of nine patients is provided. EXPERT OPINION: The impact of GJ on CYP 3A4 appears to be the critical mechanism for the majority of GJ-to-psychopharmacotherapy interactions described in human studies or case reports. However, there are studies and cases of patients clearly showing that this is not the only route explaining the GJ effect, and at times, this particular is of no relevance and that other CYP 450 isoforms as well as drug transporting proteins might be involved. The risk of GJ-to-psychotropic drugs needs to be further evaluated in a 'real-world' setting and apply not only measures of pharmacokinetics but also treatment effectiveness and safety.

Guideline for evaluating the effects of psychotropic drugs on motor vehicle driving performance in Japan: A tiered approach for the assessment of clinically meaningful driving impairment.

In December 2022, the Ministry of Health, Labour and Welfare (MHLW) of Japan issued and implemented the guideline for evaluating the effects of psychotropic drugs on motor vehicle driving performance. This guideline recommends the use of a tiered approach to assess clinically meaningful driving impairment. It is noted that adverse events cannot be solely explained by pharmacokinetics, as the onset and duration of these events vary. Among these adverse events, those affecting alertness, such as drowsiness caused by psychotropic drugs on driving performance, are more frequently observed during initial treatment stages and dose escalation. Hence, when evaluating the effects of psychotropic drugs on driving performance, it becomes crucial to assess the persistence of clinically meaningful impairment. Therefore, the MHLW guideline, developed by the authors, emphasizes the need to assess the temporal profile of adverse events affecting driving in all clinical trials. Additionally, the guideline states that when conducting driving studies, the timing of multiple dosing should consider not only the pharmacokinetics of the investigational drug but also its tolerance.

Tetrahydrocannabinol and Its Major Metabolites Are Not (or Are Poor) Substrates or Inhibitors of Human P-Glycoprotein [ATP-Binding Cassette (ABC) B1] and Breast Cancer Resistance Protein (ABCG2).

(-)-Δ9-Tetrahydrocannabinol (THC) is the primary psychoactive constituent of cannabis. In humans, 11-hydroxy-THC (11-OH-THC) and 11-nor-9-carboxy-THC (THC-COOH) are psychoactive and nonpsychoactive circulating metabolites of THC, respectively. Whether these cannabinoids are substrates or inhibitors of human P-glycoprotein (P-gp) or breast cancer resistance protein (BCRP) is unknown. Previous animal studies suggest that THC and its metabolites could be substrates of these transporters. Therefore, we performed Transwell, cellular accumulation, and vesicular transport assays, at pharmacologically relevant concentrations of these cannabinoids, using Madin-Darby canine kidney (MDCK) II cells or plasma membrane vesicles overexpressing human P-gp or BCRP. Neither THC nor 11-OH-THC was found to be a substrate or inhibitor of P-gp or BCRP. The efflux ratio of THC-COOH in MDCKII-BCRP cells was 1.6, which was significantly decreased to 1.0 by the BCRP inhibitor Ko143. Likewise, cellular accumulation of THC-COOH was significantly increased 1.6-fold in the presence versus absence of Ko143. THC-COOH also significantly inhibited BCRP-mediated transport of Lucifer yellow, a BCRP substrate; however, THC-COOH was neither a substrate nor an inhibitor of P-gp. Collectively, these results indicate that THC and 11-OH-THC are not substrates or inhibitors (at pharmacologically relevant concentrations) of either P-gp or BCRP. THC-COOH is a weak substrate and inhibitor of BCRP, but not of P-gp. Accordingly, we predict that P-gp/BCRP will not modulate the disposition of these cannabinoids in humans. In addition, use of these cannabinoids will not result in P-gp- or BCRP-based drug interactions. SIGNIFICANCE STATEMENT: This study systematically investigated whether Δ9-tetrahydrocannabinol (THC) and its major metabolites, 11-hydroxy-THC and 11-nor-9-carboxy-THC, are substrates and/or inhibitors of human P-gp and BCRP at pharmacologically relevant concentrations. The results obtained are highly valuable for mechanistic understanding and prediction of the roles of P-gp and BCRP in determining the human pharmacokinetics, tissue distribution, and drug interactions of cannabinoids.

Psychotropic Drugs and the Microbiome.

The human gut microbiome plays a key role in host physiology in health and disease. There is a growing emphasis on the bidirectional interaction between various medications and the gut microbiome. Here, we will first review how drugs can affect microbiome composition and how the microbiome can alter the pharmacodynamics and potentially pharmacokinetics of psychotropic medications. We will take into consideration different classes of psychotropics, including antipsychotics, antidepressants, antianxiety drugs, anticonvulsants/mood stabilisers, opioid analgesics, drugs of abuse, alcohol, nicotine, and xanthines. The varying effects of these widely used medications on microorganisms are becoming apparent from in vivo and in vitro studies. This has important implications for future drug discovery in psychiatry which will need to consider the host microbiome as a major potential target.

Therapeutic Drug Monitoring of Psychotropics as a Diagnostic Tool for CYP2D6 Poor Metabolizer Phenotype.

BACKGROUND: Interpatient variability in cytochrome P450 2D6 (CYP2D6) enzyme activity alters the serum concentrations of most psychotropics, which often have narrow therapeutic indices. Therefore, preemptive knowledge of CYP2D6 activity is desired. However, accessible indicators for deficient CYP2D6 activity are necessary because genotyping all patients prescribed CYP2D6 metabolized drugs is often not feasible or cost-effective. METHODS: In this study, the predictive value of the ratio between a CYP2D6 substrate and its metabolite, known as the metabolic ratio (MR), the dose-corrected serum concentration of substrate (CDR), and the dose-corrected sum concentration of substrate and metabolite (Sum CDR) of venlafaxine, risperidone, aripiprazole, and nortriptyline were determined to predict the CYP2D6 poor metabolizer (PM) phenotype. The area-under-the-receiver operator characteristic curve, as well as the sensitivity, specificity, and positive and negative predictive values of the optimal thresholds, were calculated. RESULTS: Although the MR, CDR, and Sum CDR all predicted the CYP2D6 PM phenotype, the predictive value of the MR was most robust for venlafaxine and aripiprazole, and the Sum CDR was inferior for all 3 psychotropics. MRs of venlafaxine, risperidone, and aripiprazole, and CDR of nortriptyline showed an area-under-the-receiver operator characteristics (95% confidence interval) of 97.2% (94.7%-99.6%), 93.0% (88.8%-97.2%), 97.8% (95.4%-100.0%), and 85.6% (78.0%-93.1%), respectively. Thresholds of the log(MR) of ≥0.1 for venlafaxine, ≥0.0 for risperidone, and ≥1.5 for aripiprazole, and log(CDR) ≥0.5 for nortriptyline produced >92% sensitivity and >64% specificity. CONCLUSIONS: If therapeutic drug monitoring is available, the thresholds presented here could serve as a diagnostic tool for the CYP2D6 PM phenotype of psychiatric patients prescribed the aforementioned psychotropic medications.

Brain serotonin 2A receptor binding predicts subjective temporal and mystical effects of psilocybin in healthy humans.

BACKGROUND: Psilocybin is a serotonergic psychedelic with psychoactive effects mediated by serotonin 2A receptor (5-HT2AR) activation. It produces an acute psychedelic altered state of consciousness with a unique phenomenology that can be temporally characterized by three intensity phases: onset of psychoactive effect, a peak plateau and return to normal consciousness. AIMS: We evaluated whether pre-drug brain 5-HT2AR binding predicted the three phases of psilocybin subjective drug intensity (SDI) and retrospective self-report of mystical type experiences in healthy individuals. METHOD: Sixteen participants completed a pre-drug [11C]Cimbi-36 positron emission tomography scan to assess 5-HT2AR binding. On a separate day, participants completed a single psilocybin session (oral dose range 0.2-0.3 mg/kg), during which SDI was assessed every 20 min. The Mystical Experience Questionnaire (MEQ) was completed at the end of the session. The three SDI phases were modelled using segmented linear regressions. We evaluated the associations between neocortex 5-HT2AR binding and SDI/MEQ outcomes using linear regression models. RESULTS: Neocortex 5-HT2AR was statistically significantly negatively associated with peak plateau duration and positively with time to return to normal waking consciousness. It was also statistically significantly negatively associated with MEQ total score. CONCLUSION: This is the first study to investigate how individual brain 5-HT2AR binding predicts subjective effects of a single dose of psilocybin. Our findings reinforce the role of cerebral 5-HT2AR in shaping the temporal and mystical features of the psychedelic experience. Future studies should examine whether individual brain levels of 5-HT2AR have an impact on therapeutic outcomes in clinical studies.

Oxytocin-induced facilitation of learning in a probabilistic task is associated with reduced feedback- and error-related negativity potentials.

BACKGROUND: Feedback evaluation of actions and error response detection are critical for optimizing behavioral adaptation. Oxytocin can facilitate learning following social feedback but whether its effects vary as a function of feedback valence remains unclear. AIMS: The present study aimed to investigate whether oxytocin would influence responses to positive and negative feedback differentially or equivalently. METHODS: The present study employed a randomized, double-blind, placebo controlled within-subject design to investigate whether intranasal oxytocin (24 IU) influenced behavioral and evoked electrophysiological potential responses to positive or negative feedback in a probabilistic learning task. RESULTS: Results showed that oxytocin facilitated learning and this effect was maintained in the absence of feedback. Using novel stimulus pairings, we found that oxytocin abolished bias towards learning more from negative feedback under placebo by increasing accuracy for positively reinforced stimuli. Oxytocin also decreased the feedback-related negativity difference (negative minus positive feedback) during learning, further suggesting that it rendered the evaluation of positive and negative feedback more equivalent. Additionally, post-learning oxytocin attenuated error-related negativity amplitudes but increased the late error positivity, suggesting that it may lower conflict detection between actual errors and expected correct responses at an early stage of processing but at a later stage increase error awareness and motivation for avoiding them. CONCLUSIONS: Oxytocin facilitates learning and subsequent performance by rendering the impact of positive relative to negative feedback more equivalent and also by reducing conflict detection and increasing error awareness, which may be beneficial for behavioral adaption.

Clinical Psychopharmacology for the Exotic Animal Practitioner.

Literature regarding the clinical use of psychotropic drugs in exotic animals remains scarce. Psychotropic drugs acting on serotonin, dopamine, norepinephrine, and gamma-aminobutyric acid pathways work by decreasing fear and anxiety, reactivity, and hypervigilance, and by improving impulse control. They are indicated for some cases of aggression, self-mutilation, and compulsive and anxiety disorders, including feather-damaging behavior. Side effects are rarely seen when dosages are appropriately adjusted to the individual, starting with a low dose and slowly titrating to effect. Several drug interactions exist between psychotropic drugs and other classes. Psychotropic drugs cannot be used to replace appropriate environmental conditions in exotic animals. before "Side effects".

"Little more than a gut feeling?"-considerations when prescribing psychotropic medications to patients undergoing bariatric surgery.

OBJECTIVE: Bariatric surgical procedures are being commonly performed increasingly, and many surgical candidates are concomitantly taking psychotropic medication. This paper aims to elucidate issues when prescribing psychiatric medication in this setting of substantial anatomical and physiological change. METHOD: A hand search of the literature to assess the current understanding of effects of various bariatric procedures on the bioavailability of psychotropic medication. RESULTS: Predominantly malabsorptive bariatric procedures may reduce bioavailability of some but not all commonly used psychiatric medications. There is minimal information about the effects of the most commonly performed surgery, vertical sleeve gastrectomy. Lithium prescription and monitoring requires caution. CONCLUSIONS: There is limited guidance for prescription for psychotropic medication in the bariatric surgery patient group, and vigilance for unexpected adverse effects or altered efficacy is warranted.

Pharmacokinetics of Cannabis Brownies: A Controlled Examination of Δ9-Tetrahydrocannabinol and Metabolites in Blood and Oral Fluid of Healthy Adult Males and Females.

Oral cannabis products (a.k.a. "edibles") have increased in popularity in recent years. Most prior controlled pharmacokinetic evaluations of cannabis have focused on smoked cannabis and included males who were frequent cannabis users. In this study, 17 healthy adults (8 females), with no cannabis use in at least the past 2 months, completed 4 double-blind outpatient sessions where they consumed cannabis brownies containing Δ9-tetrahydrocannabinol (THC) doses of 0, 10, 25 or 50 mg. Whole blood and oral fluid specimens were collected at baseline and for 8 h post-brownie ingestion. Enzyme-linked immunosorbent assay (ELISA) and liquid chromatography-tandem mass spectrometry (LC-MS-MS) were used to measure THC and relevant metabolites. In whole blood, concentrations of THC and 11-hydroxy-THC (11-OH-THC) peaked 1.5-2 h after brownie consumption, decreased steadily thereafter, and typically returned to baseline within 8 h. Blood concentrations for 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THCCOOH) and THCCOOH-glucuronide were higher than THC and 11-OH-THC and these metabolites were often still detected 8 h post-brownie consumption. Women displayed higher peak concentrations for THC and all metabolites in whole blood compared to men, at least partially owing to their lower body weight/body mass index. Detection of THC in oral fluid was immediate and appeared to reflect the degree of cannabis deposition in the oral cavity, not levels of THC circulating in the blood. THC concentrations were substantially higher in oral fluid than in blood; the opposite trend was observed for THCCOOH. Agreement between ELISA and LC-MS-MS results was high (i.e., over 90%) for blood THCCOOH and oral fluid THC but comparatively low for oral fluid THCCOOH (i.e., 67%). Following oral consumption of cannabis, THC was detected in blood much later, and at far lower peak concentrations, compared to what has been observed with inhaled cannabis. These results are important given the widespread use of toxicological testing to detect recent use of cannabis and/or to identify cannabis intoxication.

[Informations on psychotropics and their adaptations for patients suffering from mental disorders in France during the SARS-CoV-2 epidemic]. / Informations relatives aux psychotropes et à leurs adaptations éventuelles pour les patients souffrant de troubles psychiques en France pendant l'épidémie à SARS-CoV-2.

The 2019-20 coronavirus pandemic (SARS-CoV-2; severe acute respiratory syndrome coronavirus 2) has dramatic consequences on populations in terms of morbidity and mortality and in social terms, the general confinement of almost half of the world's population being a situation unprecedented in history, which is difficult today to measure the impact at the individual and collective levels. More specifically, it affects people with various risk factors, which are more frequent in patients suffering from psychiatric disorders. Psychiatrists need to know: (i) how to identify, the risks associated with the prescription of psychotropic drugs and which can prove to be counterproductive in their association with COVID-19 (coronavirus disease 2019), (ii) how to assess in terms of benefit/risk ratio, the implication of any hasty and brutal modification on psychotropic drugs that can induce confusion for a differential diagnosis with the evolution of COVID-19. We carried out a review of the literature aimed at assessing the specific benefit/risk ratio of psychotropic treatments in patients suffering from COVID-19. Clinically, symptoms suggestive of COVID-19 (fever, cough, dyspnea, digestive signs) can be caused by various psychotropic drugs and require vigilance to avoid false negatives and false positives. In infected patients, psychotropic drugs should be used with caution, especially in the elderly, considering the pulmonary risk. Lithium and Clozapine, which are the reference drugs in bipolar disorder and resistant schizophrenia, warrant specific attention. For these two treatments the possibility of a reduction in the dosage - in case of minimal infectious signs and in a situation, which does not allow rapid control - should ideally be considered taking into account the clinical response (even biological; plasma concentrations) observed in the face of previous dose reductions. Tobacco is well identified for its effects as an inducer of CYP1A2 enzyme. In a COVID+ patient, the consequences of an abrupt cessation of smoking, particularly related with the appearance of respiratory symptoms (cough, dyspnea), must therefore be anticipated for patients receiving psychotropics metabolized by CYP1A2. Plasma concentrations of these drugs are expected to decrease and can be related to an increase risk of relapse. The symptomatic treatments used in COVID-19 have frequent interactions with the most used psychotropics. If there is no curative treatment for infection to SARS-CoV-2, the interactions of the various molecules currently tested with several classes of psychotropic drugs (antidepressants, antipsychotics) are important to consider because of the risk of changes in cardiac conduction. Specific knowledge on COVID-19 remains poor today, but we must recommend rigor in this context in the use of psychotropic drugs, to avoid adding, in patients suffering from psychiatric disorders, potentially vulnerable in the epidemic context, an iatrogenic risk or loss of efficiency.

Psychotropic drug concentrations and clinical outcomes in children and adolescents: a systematic review.

INTRODUCTION: The use of psychotropic drugs in children and adolescents is widespread but associated with suboptimal treatment effects. Therapeutic drug monitoring (TDM) can improve safety of psychotropic drugs in children and adolescents but is not routinely performed. A major reason is that the relationship between drug concentrations and effects is not well known. AREAS COVERED: This systematic review evaluated studies assessing the relationship between psychotropic drug concentrations and clinical outcomes in children and adolescents, including antipsychotics, psychostimulants, alpha-agonists, antidepressants, and mood-stabilizers. PRISMA guidelines were used and a quality assessment of the retrieved studies was performed. Sixty-seven eligible studies involving 24 psychotropic drugs were identified from 9,298 records. The findings were generally heterogeneous and the majority of all retrieved studies were not of sufficient quality. For 11 psychotropic drugs, a relationship between drug concentrations and side-effects and/or effectiveness was evidenced in reasonably reported and executed studies, but these findings were barely replicated. EXPERT OPINION: In order to better support routine TDM in child- and adolescent psychiatry, future work must improve in aspects of study design, execution and reporting to demonstrate drug concentration-effect relationships. The quality criteria proposed in this work can guide future TDM research. Systematic review protocol and registration PROSPERO CRD42018084159.