-
Journal of Pharmacological and... May 2024Receptor occupancy is an indicator of antipsychotic efficacy and safety. It is desirable to simultaneously determine the occupancy of multiple brain receptors as an...
Development of simultaneous determination of dopamine 2, histamine 1, and muscarinic acetylcholine receptor occupancies by antipsychotics using liquid chromatography with tandem mass spectrometry.
Receptor occupancy is an indicator of antipsychotic efficacy and safety. It is desirable to simultaneously determine the occupancy of multiple brain receptors as an indicator of the efficacy and central side effects of antipsychotics because many of these drugs have binding affinities for various receptors, such as dopamine 2 (D), histamine 1 (H), and muscarinic acetylcholine (mACh) receptors. The purpose of this study was to develop a method for the simultaneous measurement of multiple receptor occupancies in the brain by the simultaneous quantification of unlabeled tracer levels using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Rats were pre-administered with a vehicle, displacer, or olanzapine, and mixed solutions of raclopride, doxepin, and 3-quinuclidinyl benzilate (3-QNB) were administered (3, 10, and 30 μg/kg). The brain tissue and plasma tracer concentrations were quantified 45 min later using LC-MS/MS, and the binding potential was calculated. The highest binding potential was observed at 3 μg/kg raclopride, 10 μg/kg doxepin, and 30 μg/kg 3-QNB. Tracer-specific binding at these optimal tracer doses in the cerebral cortex was markedly reduced by pre-administration of displacers. D, H and mACh receptor occupancy by olanzapine increased in a dose-dependent manner, reaching 70-95%, 19-43%, and 12-45%, respectively, at an olanzapine dose range of 3-10 mg/kg. These results suggest that simultaneous determination of in vivo D, H, and mACh receptor occupancy is possible using LC-MS/MS.
PubMed: 38797366
DOI: 10.1016/j.vascn.2024.107518 -
Medicine Mar 2024Lipid emulsion has been shown to effectively relieve refractory cardiovascular collapse resulting from toxic levels of nonlocal anesthetics. The goal of this study was... (Review)
Review
Lipid emulsion has been shown to effectively relieve refractory cardiovascular collapse resulting from toxic levels of nonlocal anesthetics. The goal of this study was to examine the effect of lipid emulsions on neuropsychiatric drug-induced toxicity using relevant case reports of human patients, with a particular focus on the Glasgow Coma Scale (GCS) score and corrected QT interval, to analyze drugs that frequently require lipid emulsion treatment. The following keywords were used to retrieve relevant case reports from PubMed: "antidepressant or antipsychotic drug or amitriptyline or bupropion or citalopram or desipramine or dosulepin or dothiepin or doxepin or escitalopram or fluoxetine or haloperidol or olanzapine or phenothiazine or quetiapine or risperidone or trazodone" and "lipid emulsion or Intralipid." Lipid emulsion treatment reversed the corrected QT interval prolongation and decreases in Glasgow Coma Scale scores caused by toxic doses of neuropsychiatric drugs, especially lipid-soluble drugs such as amitriptyline, trazodone, quetiapine, lamotrigine, and citalopram. The log P (octanol/water partition coefficient) of the group which required more than 3 lipid emulsion treatments was higher than that that of the group which required less than 3 lipid emulsion treatments. The main rationale to administer lipid emulsion as an adjuvant was as follows: hemodynamic depression intractable to supportive treatment (88.3%) > lipophilic drugs (8.3%) > suspected overdose or no spontaneous breathing (1.6%). Adjuvant lipid emulsion treatment contributed to the recovery of 98.30% of patients with neuropsychiatric drug-induced toxicity. However, further analyses using many case reports are needed to clarify the effects of lipid emulsion resuscitation.
Topics: Humans; Quetiapine Fumarate; Amitriptyline; Citalopram; Fat Emulsions, Intravenous; Trazodone; Drug-Related Side Effects and Adverse Reactions; Dothiepin
PubMed: 38489675
DOI: 10.1097/MD.0000000000037612 -
Molecular Pharmaceutics Dec 2023Many drugs have chiral centers and are therapeutically applied as racemates. Thus, the stereoselectivity in their interactions with membrane transporters needs to be...
Many drugs have chiral centers and are therapeutically applied as racemates. Thus, the stereoselectivity in their interactions with membrane transporters needs to be addressed. Here, we studied stereoselectivity in inhibiting organic cation transporters (OCTs) 1, 2, and 3 and the high-affinity monoamine transporters (MATs) NET and SERT. Selectivity by the inhibition of 35 pairs of enantiomers significantly varied among the three closely related OCTs. OCT1 inhibition was nonselective in almost all cases, whereas OCT2 was stereoselectively inhibited by 45% of the analyzed drugs. However, the stereoselectivity of the OCT2 was only moderate with the highest selectivity observed for pramipexole. The ()-enantiomer inhibited OCT2 4-fold more than the ()-enantiomer. OCT3 showed the greatest stereoselectivity in its inhibition. ()-Tolterodine and ()-zolmitriptan inhibited OCT3 11-fold and 25-fold more than their respective counterparts. Interestingly, in most cases, the pharmacodynamically active enantiomer was also the stronger OCT inhibitor. In addition, stereoselectivity in the OCT inhibition appeared not to depend on the transported substrate. For high-affinity MATs, our data confirmed the stereoselective inhibition of NET and SERT by several antidepressants. However, the stereoselectivity measured here was generally lower than that reported in the literature. Unexpectedly, the high-affinity MATs were not significantly more stereoselectively inhibited than the polyspecific OCTs. Combining our in vitro OCT inhibition data with available stereoselective pharmacokinetic analyses revealed different risks of drug-drug interactions, especially at OCT2. For the tricyclic antidepressant doxepine, only the ()-isomer showed an increased risk of drug-drug interactions according to guidelines from regulatory authorities for renal transporters. However, most chiral drugs show only minor stereoselectivity in the inhibition of OCTs in vitro, which is unlikely to translate into clinical consequences.
Topics: Organic Cation Transporter 1; Biological Transport; Membrane Transport Proteins; Drug Interactions; Cations; Organic Cation Transport Proteins; Organic Cation Transporter 2
PubMed: 37962560
DOI: 10.1021/acs.molpharmaceut.3c00691 -
Endocrine-related Cancer Jan 2024Measurements of plasma metanephrines and methoxytyramine provide a sensitive test for diagnosis of pheochromocytoma/paraganglioma. False-positive results remain a... (Observational Study)
Observational Study
Measurements of plasma metanephrines and methoxytyramine provide a sensitive test for diagnosis of pheochromocytoma/paraganglioma. False-positive results remain a problem, particularly in patients taking norepinephrine reuptake-blocking drugs. Therefore, in this retrospective observational study, we measured plasma metanephrines and methoxytyramine in 61 patients taking norepinephrine reuptake blockers (tricyclic antidepressants or serotonin-norepinephrine reuptake inhibitors) and 17 others taking selective serotonin reuptake inhibitors, all without pheochromocytoma/paraganglioma. We highlight a singular case with strongly elevated plasma normetanephrine and methoxytyramine concentrations associated with norepinephrine reuptake blockade. Data were compared to results from 252 and 1804 respective patients with and without tumors. Plasma normetanephrine was 40% higher (P < 0.0001) in patients on norepinephrine reuptake blockers and methoxytyramine was 127% higher (P = 0.0062) in patients taking tricyclic antidepressants compared to patients not taking uptake blockers and without tumors. The corresponding false-positive rates rose (P < 0.0001) from 4.8% to 23.0% for normetanephrine and from 0.9% to 28.6% for methoxytyramine. Selective serotonin reuptake inhibitors did not increase plasma concentrations of metabolites. In the highlighted case, plasma normetanephrine and methoxytyramine were elevated more than six times above upper reference limits. A pheochromocytoma/paraganglioma, however, was excluded by functional imaging. All biochemical test results normalized after discontinuation of norepinephrine reuptake blockers. These findings clarify that norepinephrine reuptake blockers usually result in mild elevations of normetanephrine and methoxytyramine that, nevertheless, significantly increase the number of false-positive results. There can, however, be exceptions where increases in normetanephrine and methoxytyramine reach pathological levels. Such exceptions may reflect failure of centrally mediated sympathoinhibition that normally occurs with the norepinephrine reuptake blockade.
Topics: Humans; Pheochromocytoma; Normetanephrine; Antidepressive Agents, Tricyclic; Selective Serotonin Reuptake Inhibitors; Metanephrine; Paraganglioma; Norepinephrine; Adrenal Gland Neoplasms
PubMed: 37955319
DOI: 10.1530/ERC-23-0063 -
International Journal of Pharmaceutics Nov 2023Drug-eluting beads made of responsive polyelectrolyte networks are used in the treatment of liver cancer. Aggregates of loaded drugs in complex with the networks...
Drug-eluting beads made of responsive polyelectrolyte networks are used in the treatment of liver cancer. Aggregates of loaded drugs in complex with the networks dissolve upon release, causing swelling of the network. According to a recent mechanism the release and swelling rates are controlled by the mass transport of drug through a depletion layer created in the microgel. We hypothesise that the mechanism, in which the stability of the drug aggregates and the swelling properties of the network play crucial roles, offers means to control the release profile also for other drugs. To test this, we investigated the loading and release properties of amitriptyline, chlorpromazine and doxepin in polyacrylate, hyaluronate and DCbead™ microgels in a microfluidic setup. Loaded drugs could be released to a medium with physiological ionic strength and pH. The binding strength increased with decreasing critical micelle concentration of the drugs and increasing linear charge density of network chains. Microgels displayed drug-rich core/swollen shell coexistence, and swelled during release at a rate in agreement with the depletion layer mechanism, indicating its generality. The results demonstrate the potential of microgels as vehicles for amphiphilic drugs and the usefulness of the microfluidics method for in vitro studies of such systems.
Topics: Microfluidics; Gels; Microgels; Glycosaminoglycans; Antidepressive Agents
PubMed: 37871867
DOI: 10.1016/j.ijpharm.2023.123517 -
Cureus Aug 2023Public health efforts to reduce the opioid overdose epidemic and treat opioid use disorder (OUD) have met with challenges associated with current non-standardized... (Review)
Review
Public health efforts to reduce the opioid overdose epidemic and treat opioid use disorder (OUD) have met with challenges associated with current non-standardized approaches to managing opioid withdrawal symptoms, such as itching, jitteriness, anxiety, depression, craving, vomiting, diarrhea, insomnia, and anorexia. These symptoms pose substantial obstacles to the safe initiation of medications for OUD, maintenance of long-term sobriety, and prevention of relapse. In clinical practice, multiple medications (polypharmacy) are prescribed to manage these withdrawal symptoms, including ondansetron and promethazine for vomiting and nausea, loperamide and Lomotil for diarrhea, hydroxyzine and doxepin for pruritus, benzodiazepines, the Z-drugs, and melatonin for insomnia, and benzos, tricyclic antidepressants (TCAs), and various serotonergic agents for anxiety. This polypharmacy is associated with an increased risk of adverse drug-drug interactions and adverse drug events, increased medical costs, and increased odds of medication non-adherence and relapse. We propose an alternative single medication, mirtazapine, a noradrenergic and specific serotonergic receptor antagonist, that can be used for myriad symptoms of opioid withdrawal. Case series, clinical studies, and clinical trials have shown mirtazapine to be effective for treating nausea and vomiting resulting from multiple etiologies, including hyperemesis gravidarum and chemotherapy-induced emesis. Other evidence supports the salutary effects of mirtazapine on itching and craving. Research findings support mirtazapine's beneficial effects on diarrhea and anxiety, a consequence of its modulating effects on serotonergic receptors mediating mood and gastrointestinal symptoms. There is also evidence supporting its efficacy as a potent and non-addictive sleep aid, which presents itself as a solution for insomnia associated with opioid withdrawal. The current review presents evidence from extant literature supporting mirtazapine as a one-drug strategy to treat the variety of symptoms of opioid withdrawal. This one-drug strategy has much potential to decrease polypharmacy, adverse drug events, relapse, and healthcare cost and increase the likelihood of prolonged sobriety and better quality of life for people living with OUD.
PubMed: 37736438
DOI: 10.7759/cureus.43821 -
The Journal of Family Practice Jul 2023Insomnia is a distinct disorder that is common, yet underrecognized and undertreated in primary care. Treating insomnia has been shown to improve outcomes, including... (Review)
Review
Insomnia is a distinct disorder that is common, yet underrecognized and undertreated in primary care. Treating insomnia has been shown to improve outcomes, including reduced risk of developing cardiovascular and mental health disorders. Insomnia is influenced by the brain's regulation of sleep and wake, which are mutually exclusive events. Insomnia should be treated as a distinct condition, even when occurring with a comorbid diagnosis such as depression or anxiety. Clinicians should implement a multimodal approach to insomnia management, including nonpharmacologic interventions and pharmacologic therapy (when indicated). Pharmacologic agents that are approved by the US Food and Drug Administration for insomnia include benzodiazepine receptor agonists (zolpidem, eszopiclone, and zaleplon), low-dose doxepin (tricyclic antidepressant), ramelteon (melatonin receptor agonist), and dual orexin receptor agonists (DORAs, daridorexant, lemborexant, and suvorexant). Unlike other pharmacologic agents, DORAs inhibit wakefulness rather than induce sedation. Additionally, these medications have no evidence of rebound insomnia or withdrawal, and little to no abuse potential. Daridorexant is the newest DORA, has an ideal half-life of 8 hours, and has demonstrated continued efficacy over a 12-month period. Selection of pharmacologic agent should be based on the patient's comorbid conditions, treatment goals and preferences, and other clinical characteristics.
Topics: Humans; Sleep Initiation and Maintenance Disorders; Sleep; Zolpidem; Doxepin
PubMed: 37549414
DOI: 10.12788/jfp.0620 -
The Primary Care Companion For CNS... Jul 2023
Topics: Humans; Doxepin; Hypoglycemia; Depressive Disorder
PubMed: 37419456
DOI: 10.4088/PCC.22cr03367 -
Journal of Neurogastroenterology and... Jul 2023Stigma related with antidepressants is prevalent in patients with functional dyspepsia. It affects medication compliance and efficacy. Herbal medicine acquired a...
BACKGROUND/AIMS
Stigma related with antidepressants is prevalent in patients with functional dyspepsia. It affects medication compliance and efficacy. Herbal medicine acquired a deep-rooted cultural identity in relieving dyspeptic symptoms in Asians. The research was designed to compare the effectiveness of Zhizhu Kuanzhong capsules (ZZKZ) versus doxepin hydrochloride (doxepin) on alleviating stigma and medication nonadherence among patients with refractory FD (rFD).
METHODS
Patients with rFD from February 2021 to February 2022 were randomly allocated to receive either doxepin (n = 56) or ZZKZ (n = 57) combined with omeprazole for 4 weeks. Medication possession ratio (MPR), the disease- and medication-associated stigma were analyzed. The scales were utilized to assess dyspeptic symptoms (Leeds Dyspepsia Questionnaire) and psychological conditions (Generalized Anxiety Disorder Questionnaire and Patient Health Questionnaire).
RESULTS
The MPR values for ZZKZ were significantly higher than those for doxepin ( < 0.001). The stigma scores decreased in ZZKZ group while increased in doxepin group compared to baseline after treatment. The proportion of patients showing ZZKZ-associated stigma was significantly lower than doxepin-associated stigma ( < 0.001). The MPR values were negatively correlated with post-treatment stigma scores in both groups ( < 0.001). Dyspeptic symptoms and psychological condition were improved in both groups after treatment, with no significant difference on post-treatment Leeds Dyspepsia Questionnaire, Generalized Anxiety Disorder Questionnaire, or Patient Health Questionnaire scores between 2 groups.
CONCLUSION
ZZKZ is superior to doxepin in alleviating stigma and medication non-adherence, with comparable efficacy in improving dyspeptic symptoms and psychological condition of patients with rFD.
PubMed: 37417263
DOI: 10.5056/jnm22145