-
Neuroscience Bulletin May 2024Neuroinflammation mediated by microglia and oxidative stress play pivotal roles in the development of chronic temporal lobe epilepsy (TLE). We postulated that kainic...
Neuroinflammation mediated by microglia and oxidative stress play pivotal roles in the development of chronic temporal lobe epilepsy (TLE). We postulated that kainic acid (KA)-Induced status epilepticus triggers microglia-dependent inflammation, leading to neuronal damage, a lowered seizure threshold, and the emergence of spontaneous recurrent seizures (SRS). Extensive evidence from our laboratory suggests that dextromethorphan (DM), even in ultra-low doses, has anti-inflammatory and neuroprotective effects in many animal models of neurodegenerative disease. Our results showed that administration of DM (10 ng/kg per day; subcutaneously via osmotic minipump for 4 weeks) significantly mitigated the residual effects of KA, including the frequency of SRS and seizure susceptibility. In addition, DM-treated rats showed improved cognitive function and reduced hippocampal neuronal loss. We found suppressed microglial activation-mediated neuroinflammation and decreased expression of hippocampal gp91 and p47 proteins in KA-induced chronic TLE rats. Notably, even after discontinuation of DM treatment, ultra-low doses of DM continued to confer long-term anti-seizure and neuroprotective effects, which were attributed to the inhibition of microglial NADPH oxidase 2 as revealed by mechanistic studies.
Topics: Animals; Epilepsy, Temporal Lobe; Kainic Acid; Dextromethorphan; Neuroprotective Agents; Male; NADPH Oxidases; Rats, Sprague-Dawley; Microglia; Hippocampus; Rats; Anticonvulsants; Disease Models, Animal; Chronic Disease
PubMed: 37973720
DOI: 10.1007/s12264-023-01140-8 -
Psychedelic Medicine (New Rochelle,... Dec 2023N-methyl-D-aspartate receptor-mediated dissociatives and serotonergic hallucinogens are being increasingly used in therapeutic interventions that involve nonordinary...
RATIONALE
N-methyl-D-aspartate receptor-mediated dissociatives and serotonergic hallucinogens are being increasingly used in therapeutic interventions that involve nonordinary states of consciousness and may represent a unique mental health paradigm wherein pharmacologically induced experiences are conducive to psychological well-being.
OBJECTIVE
The aim of this study was to further understand how the phenomenological and health-promoting effects of high-dose dextromethorphan (DXM) compared to psilocybin in the same participants when administered under experimental conditions that are typical of therapeutic psychedelic trials.
METHODS
Single, acute oral doses of DXM (400 mg/70 kg), psilocybin (10, 20, 30 mg/70 kg), and inactive placebo were administered under double-blind and psychologically supportive conditions to 20 healthy participants with histories of hallucinogen use. Ratings of personal meaning, spiritual significance, psychological challenge, and psychological insight attributed to acute drug experiences were assessed 7 h (at session end) and 1 week after each drug administration. Persisting psychological effects were assessed 1 week after each drug administration.
RESULTS
High-dose DXM and psilocybin produced similar increases over placebo in ratings of drug experience that was predictive of psychological benefit at 1 week, even when expectancy effects were minimized. These effects tended to favor psilocybin in a dose-dependent manner and were limited by poor physical tolerability for DXM.
CONCLUSIONS
This analysis suggests the utility of exploring clinical applications of dissociatives that occur within the supportive contexts that are characteristic of psychedelic research and that prioritize the optimization of psychologically valuable drug experiences. This study was registered with ClinicalTrials.gov (NCT02033707).
PubMed: 38152462
DOI: 10.1089/psymed.2023.0035 -
Journal of UOEH 2024A woman in her 30s who was being treated for a mental illness with several psychotropic drugs was admitted to the hospital after being found in a state of...
A woman in her 30s who was being treated for a mental illness with several psychotropic drugs was admitted to the hospital after being found in a state of unconsciousness and respiratory arrest at home. She was pronounced dead 12 hours after she was discovered. Her autopsy revealed symmetrical hemorrhagic necrosis in the putamen on both sides of her cerebrum. Although many drugs were detected in her blood, all of those other than dextromethorphan (DXM) were within or below the therapeutic range. Her blood DXM was 1.73 μg/ml at admission and 1.61 μg/ml at autopsy, which were within the toxic range or coma-to-death range. The cause of death was diagnosed as DXM poisoning. DXM can cause hallucinations and euphoria if taken in excess, but since it is available as an over-the-counter drug at general pharmacies, an increasing number of young people are overdosing on it, mistakenly believing it to be a safe drug with few side effects. We believe that further social measures against DXM are necessary in Japan, such as disseminating correct knowledge in society and regulating over-the-counter sales.
Topics: Humans; Dextromethorphan; Female; Autopsy; Adult; Fatal Outcome
PubMed: 38839290
DOI: 10.7888/juoeh.46.221 -
Annals of Clinical and Translational... Aug 2023No efficacious treatments exist to improve or prolong bulbar functions of speech and swallowing in persons with amyotrophic lateral sclerosis (pALS). This study...
OBJECTIVE
No efficacious treatments exist to improve or prolong bulbar functions of speech and swallowing in persons with amyotrophic lateral sclerosis (pALS). This study evaluated the short-term impact of dextromethorphan/quinidine (DMQ) treatment on speech and swallowing function in pALS.
METHODS
This was a cohort trial conducted between August 2019 to August 2021 in pALS with a confirmed diagnosis of probable-definite ALS (El-Escorial Criteria-revisited) and bulbar impairment (ALS Functional Rating Scale score ≤ 10 and speaking rate ≤ 140 words per minute) who were DMQ naïve. Efficacy of DMQ was assessed via pre-post change in the ALS Functional Rating Scale-Revised bulbar subscale and validated speech and swallowing outcomes. Paired t-tests, Fisher's exact, and χ tests were conducted with alpha at 0.05.
RESULTS
Twenty-eight pALS enrolled, and 24 participants completed the 28-day trial of DMQ. A significant increase in ALSFRS-R bulbar subscale score pre- (7.47 ± 1.98) to post- (8.39 ± 1.79) treatment was observed (mean difference: 0.92, 95% CI: 0.46-1.36, p < 0.001). Functional swallowing outcomes improved, with a reduction in unsafe (75% vs. 44%, p = 0.003) and inefficient swallowing (67% vs. 58%, p = 0.002); the relative speech event duration in a standard reading passage increased, indicating a greater duration of uninterrupted speech (mean difference: 0.33 s, 95% CI: 0.02-0.65, p = 0.035). No differences in diadochokinetic rate or speech intelligibility were observed (p > 0.05).
INTERPRETATION
Results of this study provide preliminary evidence that DMQ pharmacologic intervention may have the potential to improve or maintain bulbar function in pALS.
Topics: Humans; Amyotrophic Lateral Sclerosis; Dextromethorphan; Quinidine; Deglutition; Speech
PubMed: 37265174
DOI: 10.1002/acn3.51821 -
Journal of Clinical Medicine Sep 2023Among patients with chronic cough (CC) in the 2012-2021 statewide OneFlorida Clinical Research Consortium database, we examined trends in cough medication (CM)...
Among patients with chronic cough (CC) in the 2012-2021 statewide OneFlorida Clinical Research Consortium database, we examined trends in cough medication (CM) prescribing prevalence over time in repeated cross-sectional analyses and identified distinct CM utilization trajectories using group-based trajectory modeling (GBTM) in a retrospective cohort study. Among eligible adults (≥18 years) without cancer/benign respiratory tumor diagnoses, we identified CC patients and non-CC patients with any cough-related diagnosis. In the GBTM analysis, we calculated the number of monthly prescriptions for any CMs (excluding gabapentinoids) during the 12 months from the first qualifying cough event to identify distinct utilization trajectories. From 2012 to 2021, benzonatate (9.6% to 26.1%), dextromethorphan (5.2% to 8.6%), and gabapentinoid (5.3% to 14.4%) use increased among CC patients, while opioid antitussive use increased from 2012 to 2015 and decreased thereafter (8.4% in 2012, 14.7% in 2015, 6.7% in 2021; all < 0.001). Of 15,566 CC patients and 655,250 non-CC patients identified in the GBTM analysis, CC patients had substantial burdens of respiratory/non-respiratory comorbidities and healthcare service and concomitant medication use compared to non-CC patients. Among CC patients, GBTM identified three distinct CM utilization trajectories: (1) no CM use (n = 11,222; 72.1%); (2) declining CM use (n = 4105; 26.4%); and (3) chronic CM use (n = 239; 1.5%). CC patients in Florida had limited CM use with increasing trends in use of benzonatate, dextromethorphan, and gabapentinoids and a decreasing trend in opioid antitussive use. CC patients, particularly with chronic prescription CM use, experienced substantial disease burden.
PubMed: 37834931
DOI: 10.3390/jcm12196286 -
Current Drug Metabolism Mar 2024Asunaprevir, daclatasvir, and beclabuvir are direct-acting antiviral agents used in the treatment of patients infected with hepatitis C genotype 1b. This article reviews...
The Role of CYPs and Transporters in the Biotransformation and Transport of the Anti-hepatitis C Antiviral Agents Asunaprevir, Daclatasvir, and Beclabuvir: Impact of Liver Disease, Race and Drug-drug Interactions on Safety and Efficacy.
Asunaprevir, daclatasvir, and beclabuvir are direct-acting antiviral agents used in the treatment of patients infected with hepatitis C genotype 1b. This article reviews the biotransformation and disposition of these drugs in relation to the safety and efficacy of therapy. CYP3A4 and 3A5 catalyze the oxidative biotransformation of the drugs, while P-glycoprotein mediates their efflux from tissues. Asunaprevir is also a substrate for the influx transporters OATP1B1 and OATP2B1 and the efflux transporter MRP2, while beclabuvir is also a substrate for the efflux transporter BCRP. Liver disease decreases the expression of CYPs and transporters that mediate drug metabolism and disposition. Serum asunaprevir concentrations, but not those of daclatasvir or beclabuvir, are increased in patients with severe liver disease, which may produce toxicity. Pharmacogenomic variation in CYPs and transporters also has the potential to disrupt therapy with asunaprevir, daclatasvir and beclabuvir; some variants are more prevalent in certain racial groups. Pharmacokinetic drug-drug interactions, especially where asunaprevir, daclatasvir, and beclabuvir are victim drugs, are mediated by coadministered rifampicin, ketoconazole and ritonavir, and are attributable to inhibition and/or induction of CYPs and transporters. Conversely, there is also evidence that asunaprevir, daclatasvir and beclabuvir are perpetrators of drug interactions with coadministered rosuvastatin and dextromethorphan. Together, liver disease, pharmacogenomic variation and drug-drug interactions may disrupt therapy with asunaprevir, daclatasvir and beclabuvir due to the impaired function of important CYPs and transporters.
PubMed: 38441017
DOI: 10.2174/0113892002288832240213095622 -
American Journal of Veterinary Research May 2024Develop a cytochrome P450 (CYP) phenotyping cocktail for dogs using specific substrates for hepatic P450 enzymes CYP2B11, CYP2D15, and CYP3A12 and determine whether...
OBJECTIVE
Develop a cytochrome P450 (CYP) phenotyping cocktail for dogs using specific substrates for hepatic P450 enzymes CYP2B11, CYP2D15, and CYP3A12 and determine whether alternative sampling methods (saliva and urine) or single time point samples could be used instead of multiple blood sampling.
ANIMALS
12 healthy client-owned dogs (8 females and 4 males) from February 2019 to May 2019.
METHODS
In a randomized crossover study, dogs received oral administration of the probe drug bupropion (75 mg), dextromethorphan (30 mg), or omeprazole (40 mg) alone or as a 3-drug combination (Program in Individualized Medicine [PrIMe] cocktail) to evaluate simultaneous phenotyping of CYP2B11, CYP2D15, and CYP3A12. Pharmacokinetic profiles for the probe drugs and metabolites were determined using plasma, saliva, and urine. Dogs received probe drugs alone or combined. Pharmacokinetic profiles up to 6 hours postdose for the probe drugs and metabolites were determined using plasma, saliva, and urine.
RESULTS
The PrIMe cocktail was well tolerated. There was no statistically significant interaction between the probe drugs when administered together. Single time point plasma metabolic ratios at 4 hours postdose for all probe drugs strongly correlated with the corresponding area under the plasma concentration-versus-time curve (AUC) ratios. Saliva AUC metabolic ratios for CYP3A12 and CYP2D15 and 6-hour urine for CYP2B11 and CYP2D15 were correlated with plasma AUC ratios.
CONCLUSIONS
The PrIMe cocktail can be used for simultaneous CYP phenotyping using plasma 4-hour single time point sample metabolic ratios. Saliva and urine sampling are suitable for specific CYPs.
CLINICAL RELEVANCE
The PrIMe cocktail has potential as a useful tool in dogs to detect clinically important CYP-mediated drug-drug interactions, identify novel pharmacogenes, determine the drug-metabolizing phenotype of individual dogs, aid in individualized dose selection, and evaluate the effects of various physiological states on drug metabolism.
PubMed: 38718826
DOI: 10.2460/ajvr.24.02.0049 -
Neuropsychopharmacology Reports Jun 2024To investigate changes in the clinical characteristics of patients who abused benzodiazepine receptor agonists (BZRA) or over-the-counter (OTC) drugs before and after... (Comparative Study)
Comparative Study
Comparison of patients with benzodiazepine receptor agonist-related psychiatric disorders and over-the-counter drug-related psychiatric disorders before and after the COVID-19 pandemic: Changes in psychosocial characteristics and types of abused drugs.
AIM
To investigate changes in the clinical characteristics of patients who abused benzodiazepine receptor agonists (BZRA) or over-the-counter (OTC) drugs before and after COVID-19 based on the 2018 and 2022 data of the "Nationwide Psychiatric Hospital (NPH) Survey on Drug-related Psychiatric Disorders."
METHOD
A total of 446 and 155 cases, and 435 and 273 cases, who mainly abused BZRAs or OTC drugs, respectively, were extracted from the database of the two NPH Surveys. Demographic variables, education, employment, criminal record, drug use during the previous year, psychiatric diagnosis, and types of abused drugs were compared between 2018 and 2022.
RESULT
A comparison of BZRA abusers revealed a decreased number of users during the previous year and an increase in the comorbidity rate of other disorders (F3 and F4 in ICD-10) in 2022. Etizolam, flunitrazepam, triazolam, and zolpidem were used most in both years, with an increase in zolpidem and a decrease in triazolam in 2022. A comparison of OTC drug abusers revealed a higher proportion of women and young patients in 2022. An increase in the comorbidity rate of F3 and F9 and a significant increase in the use of dextromethorphan products were observed in 2022, although codeine products were in the majority in both years.
CONCLUSION
By comparing NPH Surveys before and after the COVID-19 pandemic, both BZRA abusers and OTC drug abusers present complex pathologies, requiring tailor-made treatment. The younger OTC drug abusers were particularly evident among women, and the abuse of dextromethorphan-containing OTC drugs has increased alarmingly.
Topics: Humans; Female; COVID-19; Male; Adult; Substance-Related Disorders; Nonprescription Drugs; Mental Disorders; Middle Aged; GABA-A Receptor Agonists; Young Adult; Adolescent
PubMed: 38622878
DOI: 10.1002/npr2.12440 -
BMJ Supportive & Palliative Care May 2024
PubMed: 38744449
DOI: 10.1136/spcare-2024-004917 -
Journal of Clinical PsychopharmacologyApproximately one third of individuals with major depressive disorder have treatment-resistant depression (TRD). Glutamatergic modulators such as the N -methyl- d...
BACKGROUND
Approximately one third of individuals with major depressive disorder have treatment-resistant depression (TRD). Glutamatergic modulators such as the N -methyl- d -aspartate receptor antagonist ketamine have rapid and robust antidepressant effects, but their use has been limited by accessibility and route of administration. This open-label pilot study assessed the adjunctive antidepressant efficacy of dextromethorphan/quinidine (DM/Q) in TRD.
METHODS
Inpatients with TRD (n = 17, 40.8 ± 12.3 years; 9 females/8 males) received adjunctive open-label DM/Q (20 mg/10 mg) up to 3 times daily. The study had no set endpoint; participants were followed until they discontinued DM/Q or were discharged. Montgomery-Asberg Depression Rating Scale (MADRS) scores were obtained at baseline (before DM/Q administration) and regularly during hospitalization. Full response was defined as a ≥50% reduction in baseline MADRS score, partial response as a 25% to 50% decrease in baseline MADRS score, and nonresponse as a <25% reduction or an increase in baseline MADRS score.
RESULTS
The 17 inpatients received open-label DM/Q for 5.1 ± 2.7 weeks. Forty-seven percent of participants responded to DM/Q-12% achieved a full response and 35% achieved a partial response. The largest MADRS difference observed at any time point was -6.4 ± 8.4 (-21.0% ± 29.9%), and the MADRS difference observed at time of DM/Q discontinuation or hospital discharge was -4.8 ± 8.4 (-15.9% ± 29.7%). Twenty-four percent of participants experienced a nonserious adverse event; none experienced a serious adverse event.
CONCLUSIONS
In this open-label pilot study, 47% of participants responded to adjunctive DM/Q, which was well tolerated. Larger placebo-controlled trials are needed to determine the real-world efficacy of DM/Q.
Topics: Male; Female; Humans; Quinidine; Dextromethorphan; Depressive Disorder, Major; Treatment Outcome; Depression; Pilot Projects; Antidepressive Agents; Depressive Disorder, Treatment-Resistant; Double-Blind Method
PubMed: 37683231
DOI: 10.1097/JCP.0000000000001738