Ondansetron: a review of pharmacokinetics and clinical experience in postoperative nausea and vomiting

Safety and compliance of long-term low-dose ondansetron in alcohol use disorder treatment

BACKGROUND

The increasing prevalence of alcohol use disorder (AUD) and the parallel surge in alcohol-associated liver disease (ALD) emphasize the urgent need for comprehensive alcohol management strategies. Low-dose ondansetron (AD04, a 5-HT3 antagonist) was shown recently to be a promising treatment for AUD with a specific genotypic profile (5-marker). The liver safety of AD04 has never been evaluated in subjects with AUD. The aim of the present study was to assess the liver safety profile of AD04 compared with placebo in subjects with AUD.

METHODS

Liver biochemical parameters were assessed in subjects with AUD with a 5-marker genetic profile who participated in a Phase 3 randomized controlled trial and received either twice-daily, low-dose AD04 (ondansetron 0.33 mg twice daily) or matching placebo, combined with brief psychosocial counseling. ALT, AST, GGT, Serum Bilirubin, MCV, and Prothrombin were evaluated at weeks 0, 12, and 24. Adverse cardiac events, general well-being, and study completion were also assessed.

RESULTS

Low-dose AD04 did not significantly change biochemical markers of liver injury, such as ALT, AST, and Serum Bilirubin. While patients with AUD displayed elevated GGT levels, typically associated with increased alcohol consumption, this parameter remained unaffected by low-dose AD04. Notably, no significant adverse effects were observed due to oral low-dose AD04 treatment.

CONCLUSIONS

Low-dose AD04 has the potential to be a safe treatment option for subjects with AUD and ALD, indicating the need for an RCT for this specific cohort. Such a trial would pave the way for the design of a precision treatment for combined AUD with ALD.

Pharmacological Treatment of Acute Unilateral Vestibulopathy: A Review

There have been few investigations on the epidemiology, etiology, and medical management of acute unilateral vestibulopathy (AUV). Short-term pharmaceutical resolutions include vestibular symptomatic suppressants, anti-emetics, and some cause-based therapies. Anticholinergics, phenothiazines, antihistamines, antidopaminergics, benzodiazepines, and calcium channel antagonists are examples of vestibular suppressants. Some of these medications may show their effects through multiple mechanisms. In contrast, N-acetyl-L-leucine, Ginkgo biloba, and betahistine improve central vestibular compensation. Currently, AUV pathophysiology is poorly understood. Diverse hypotheses have previously been identified which have brought about some causal treatments presently used. According to some publications, acute administration of anti-inflammatory medications may have a deleterious impact on both post-lesional functional recovery and endogenous adaptive plasticity processes. Thus, some authors do not recommend the use of corticosteroids in AUV. Antivirals are even more contentious in the context of AUV treatment. Although vascular theories have been presented, no verified investigations employing anti-clotting or vasodilator medications have been conducted. There are no standardized treatment protocols for AUV to date, and the pharmacological treatment of AUV is still questionable. This review addresses the most current developments and controversies in AUV medical treatment.

An LC-ESI-MS/MS method for determination of ondansetron in low-volume plasma and cerebrospinal fluid: Method development, validation, and clinical application

Ondansetron is used in clinical settings as an antiemetic drug. Although the animal studies showed its potential effectiveness also in treating neuropathic pain, the results from humans are inconclusive. The lack of efficacy of ondansetron in a subset of patients might be due to the overexpression of P-glycoprotein, which could result in low concentrations of ondansetron in the central nervous system (CNS). A surrogate of the CNS exposure might be drug concentration in the cerebrospinal fluid (CSF), especially in humans, as assessing the drug disposition directly in the patient's brain would be challenging. The study aimed to develop a sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to determine concentrations of ondansetron in human K3EDTA plasma and CSF. Ondansetron was extracted from biological matrices by liquid-liquid extraction. The quantification was performed on a Sciex QTRAP 6500+ mass spectrometer with labeled ondansetron as an internal standard. The calibration range was 0.25-350 ng/mL in plasma and 0.025-100 ng/mL in CSF; for both matrices, 25 µL of samples was required for the assays. The method was validated according to the FDA and EMA guidelines and showed acceptable results. A pilot study confirmed its suitability for clinical samples: after 4-16 mg of intravenous ondansetron, the determined concentrations in plasma were 1.22-235.90 ng/mL, while in CSF - 0.018-11.93 ng/mL. In conclusion, the developed method fulfilled all validation requirements and can be applied to pharmacokinetic studies assessing the CNS ondansetron exposure in humans. The method's advantages, such as a low volume of matrix and a wide calibration range, support its use in a study in which rich sampling and various drug doses are expected.

Efficacy and safety of ondansetron for morning sickness in pregnancy: a systematic review of clinical trials

Background: Ondansetron is a selective antagonist of the serotonin 5-HT3 receptor that is commonly used to treat morning sickness. It is estimated that 70%-80% of pregnant women suffer from morning sickness, a condition characterized by nausea and vomiting. However, it is still controversial regarding its safety during pregnancy, and continued research will be necessary to fully understand the risks and benefits associated with its use. Therefore, we aimed to identify and provide details of the efficacy and safety of ondansetron in clinical trials. Methods: A search was conducted of the ClinicalTrials.gov database on 13 April 2023, using the search term "ondansetron and pregnancy." Inclusion and exclusion criteria were defined to identify relevant clinical trials. The inclusion criteria encompassed clinical trials related to pregnancy that utilized ondansetron as a treatment, while other clinical trials were excluded from consideration. All data extractions such as study title, study status, study type, intervention details, and outcome were collected. Results: A total of 18 clinical trials were identified, of which only 6 focused on studying the effects of ondansetron. Their respective study titles, statuses, conditions, interventions, outcome measures, and enrollment sizes have been written in detail. The information collected from these trials will contribute to our understanding of the potential benefits and risks of ondansetron in the context of pregnancy and its complications. Conclusion: Ondansetron has been shown to be an effective treatment for nausea and vomiting, including pregnancy-related morning sickness. Further research is needed to better understand the potential risks and benefits associated with its use in pregnant women. Systematic Review Registration: ClinicalTrials.gov, identifier.

Drowsiness following ondansetron given the day after general anesthesia for postoperative nausea: a pediatric case report

BACKGROUND

Ondansetron is an antiemetic drug that is useful not only for prevention but also for the treatment of postoperative nausea and vomiting (PONV). We report a rare case of drowsiness in a child after using ondansetron for nausea on the day after general anesthesia.

CASE PRESENTATION

A 5-year-old boy underwent circumcision under general anesthesia and suffered from postoperative nausea and vomiting. He was administered 0.1mg/kg of ondansetron in the PACU and 23 h later on the day after surgery. After the second dose, he acutely exhibited drowsiness which resolved in 3 h. He was discharged to home later on the same day. He was not given any other drugs at the time, and the drowsiness was thought to be directly attributable to ondansetron, though the exact mechanism was unknown.

CONCLUSIONS

When drowsiness or other cognitive symptoms are observed after administration of ondansetron, it must be considered and managed as a possible side effect.

Hemorrhagic Posterior Reversible Encephalopathy Syndrome in a Patient With Larynx Carcinoma

Significance Statement Posterior reversible encephalopathy syndrome (PRES) is characterized by variable neurological findings such as headache, deterioration in mental condition, loss of consciousness and visual loss. The disease results with impairment of the cerebral blood flow autoregulation. Ondansetron, serotonin (5HT-3) receptor antagonist, may cause the haemorrhagic PRES.

Off-label and investigational drugs in the treatment of alcohol use disorder: A critical review

Compounds known to be successful in the treatment of alcohol use disorder include the aversive agent, Disulfiram, the glutamatergic NMDA receptor antagonist, Acamprosate, and the opioid receptor antagonists, Naltrexone and Nalmefene. Although all four are effective in maintaining abstinence or reduction of alcohol consumption, only a small percentage of patients receive pharmacological treatment. In addition, many other medications have been investigated for their therapeutic potential in the treatment of alcohol use disorder. In this review we summarize and compare Baclofen, Gabapentin, Topiramate, Ondansetron, Varenicline, Aripiprazole, Quetiapine, Clozapine, Antidepressants, Lithium, Neuropeptide Y, Neuropeptide S, Corticotropin-releasing factor antagonists, Oxytocin, PF-05190457, Memantine, Ifenprodil, Samidorphan, Ondelopran, ABT-436, SSR149415, Mifepristone, Ibudilast, Citicoline, Rimonabant, Surinabant, AM4113 and Gamma-hydroxybutyrate While some have shown promising results in the treatment of alcohol use disorder, others have disappointed and should be excluded from further investigation. Here we discuss the most promising results and highlight medications that deserve further preclinical or clinical study. Effective, patient-tailored treatment will require greater understanding provided by many more preclinical and clinical studies.

Effect of Intranasal Dexamethasone on the Incidence of Nausea and Vomiting After Adult Strabismus Surgery

Objectives

Due to the high prevalence of postoperative nausea and vomiting (PONV), this study aimed to determine the preventive effect of intranasal dexamethasone on the incidence of nausea and vomiting after adult strabismus surgery.

Methods

This randomized clinical trial study was performed on 72 patient candidates for strabismus surgery at Feiz University Hospital in Isfahan in 2020. Patients were divided into 2 groups of 36 with random allocation software and entered into the study. After induction of similar anesthesia, endotracheal intubation was performed in patients. Immediately after inflating the cuff, the first group (intranasal dexamethasone (ND)) received 1 mL of dexamethasone (4 mg) per nasal passage, and the second group (intranasal normal saline (NS)) received 1 mL of normal saline per nasal passage. Patients of the 2 groups were evaluated and compared at first 2 hours and 2 - 24 hours after surgery for the incidence and severity of nausea and vomiting, and pain after surgery. Data were analyzed using SPSS software version 23.

Results

There were no significant differences in terms of age (P = 0.304), weight (P = 0.21), gender (P = 0.81), and American Society of Anesthesiologists (ASA) Physical Status class (P = 1) between the 2 groups. In the first 2 hours after surgery, the incidence of nausea (P = 0.034) and its severity (P = 0.019) was significantly lower in the ND group compared to the NS group. Also, 24 hours after surgery, the incidence of nausea (P = 0.38) and its severity (P = 0.55) were insignificantly lower in the ND group. Both groups showed no significant difference in the incidence of vomiting at 2 hours (P = 0.11) and 24 hours (P = 0.16) postoperative. Two hours after surgery, the incidence of pain (P = 0.001) and its severity (P < 0.001), and also 24 hours after surgery, the incidence of pain (P < 0.001) and its severity (P < 0.001) were significantly lower in the ND group. Getting ondansetron (P = 0.023) and pethidine (P < 0.001), extubation time (P < 0.001), and recovery time (P = 0.03) were significantly lower in the ND group. Patients' satisfaction was significantly higher in the ND group compared to the NS group (P = 0.031).

Conclusions

The findings of the present study show that the intranasal use of dexamethasone with a dose of 8 mg compared to saline is associated with a decrease in PONV and postoperative pain, a decrease in the use of ondansetron and pethidine, and an increase in patient's satisfaction. Intranasal use of dexamethasone may be an effective and safe method, especially in cases where we do not have access to an intravenous line.

Improving ondansetron use and oral rehydration instructions for pediatric acute gastroenteritis

In paediatric patients with acute gastroenteritis (AGE), ondansetron use decreases the need for intravenous fluids, reduces hospitalisations and shortens illness duration. Oral rehydration is also known to have excellent outcomes for mild to moderate dehydration secondary to AGE. Although these interventions are recommended in guidelines from international professional societies, baseline data at our clinic showed that <2% of these patients were offered ondansetron, and that few patients received appropriately detailed rehydration instructions. Therefore, we engaged residents and fellows as teachers and leaders in our university clinic’s quality improvement programme to promote evidence-based practice for paediatric AGE. Our gap analysis identified opportunities for interventions including educating paediatricians and paediatrics residents on the safety and utility of the medication. We created standardised oral rehydration after-visit instructions and implemented a trainee-led educational approach that encouraged appropriate medication use. We used a follow-up survey to uncover provider concerns and tailor future interventions. The process metrics included: proportion of paediatric patients appropriately treated with ondansetron (goal of 80%), and proportion of patients given appropriate oral rehydration instructions. The outcome metric was 7-day representation rates. To achieve sustainability, we restructured our process to have senior residents take ownership of teaching and data collection. Trainee-driven interventions increased ondansetron prescription rates to a median of 66.6%. Patients prescribed ondansetron were less likely to represent to care, although representation rate was low overall. Postintervention data suggests that prescription rates decreased without continued interventions and additional systems redesign may help sustain impact.

Chronic Kidney Disease-Associated Itch (CKD-aI) in Children-A Narrative Review

Chronic kidney disease (CKD) is a condition of widespread epidemiology and serious consequences affecting all organs of the organism and associated with significant mortality. The knowledge on CKD is rapidly evolving, especially concerning adults. Recently, more data is also appearing regarding CKD in children. Chronic itch (CI) is a common symptom appearing due to various underlying dermatological and systemic conditions. CI may also appear in association with CKD and is termed chronic kidney disease-associated itch (CKD-aI). CKD-aI is relatively well-described in the literature concerning adults, yet it also affects children. Unfortunately, the data on paediatric CKD-aI is particularly scarce. This narrative review aims to describe various aspects of CKD-aI with an emphasis on children, based on the available data in this population and the data extrapolated from adults. Its pathogenesis is described in details, focusing on the growing role of uraemic toxins (UTs), as well as immune dysfunction, altered opioid transmission, infectious agents, xerosis, neuropathy and dialysis-associated aspects. Moreover, epidemiological and clinical aspects are reviewed based on the few data on CKD-aI in children, whereas treatment recommendations are proposed as well, based on the literature on CKD-aI in adults and own experience in managing CI in children.

Marijuana, Ondansetron, and Promethazine Are Perceived as Most Effective Treatments for Gastrointestinal Nausea

BACKGROUND

Many anti-nausea treatments are available for chronic gastrointestinal syndromes, but data on efficacy and comparative effectiveness are sparse.

AIMS

To conduct a sectional survey study of patients with chronic nausea to assess comparative effectiveness of commonly used anti-nausea treatments.

METHODS

Outpatients at a single center presenting for gastroenterology evaluation were asked to rate anti-nausea efficacy on a scale of 0 (no efficacy) to 5 (very effective) of 29 commonly used anti-nausea treatments and provide other information about their symptoms. Additional information was collected from the patients' chart. The primary outcome was to determine which treatments were better or worse than average using a t test. The secondary outcome was to assess differential response by individual patient characteristics using multiple linear regression.

RESULTS

One hundred and fifty-three patients completed the survey. The mean efficacy score of all anti-nausea treatments evaluated was 1.73. After adjustment, three treatments had scores statically higher than the mean, including marijuana (2.75, p < 0.0001), ondansetron (2.64, p < 0.0001), and promethazine (2.46, p < 0.0001). Several treatments, including many neuromodulators, complementary and alternative treatments, erythromycin, and diphenhydramine had scores statistically below average. Patients with more severe nausea responded better to marijuana (p = 0.036) and diphenhydramine (p < 0.001) and less so to metoclopramide (p = 0.020). There was otherwise no significant differential response by age, gender, nausea localization, underlying gastrointestinal cause of nausea, and GCSI.

CONCLUSIONS

When treating nausea in patients with chronic gastrointestinal syndromes, clinicians may consider trying higher performing treatments first, and forgoing lower performing treatments. Further prospective research is needed, particularly with respect to highly effective treatments.

Preparation of an oil suspension containing ondansetron hydrochloride as a sustained release parenteral formulation

Ondansetron hydrochloride (ODS) is a selective 5-hydroxytryptamine type 3 antagonist for nausea and emesis prevention in neoplastic patients. To reduce dosing frequency and side effects and improve patient compliance, a sustained release parenteral formulation of ODS was developed. Microparticles of methylcellulose (MC) and ODS were prepared using the spray-drying method and suspended in oils to form oil suspensions. The formulations were evaluated for residual moisture, drug content, size distribution, DSC, XRD, FTIR, SEM, drug release, and pharmacokinetic studies. The effects of polymers and oils on the drug release were evaluated. MC showed the most prominent sustained release effect among various polymers examined with the optimum MC/ODS ratio of 2:1 (w/w). The particle size of the produced microparticles was in the mean diameter of approximately 3 μm. Physicochemical characterization suggested that ODS existed in an amorphous matrix within the microparticles and interacted with MC via hydrogen bonds. Corn oil was selected as the appropriate oil for suspension due to the sustained release of ODS and the appropriate viscosity. The optimized sustained release formulation of ODS was the corn oil suspension of spray-dried microparticles containing MC and ODS (2:1, w/w). It showed an in vitro drug sustained release up to 120 h, while the oil suspension of ODS without any polymer released the drug within 2 h. Following subcutaneous administration in rats, the optimized formulation could prolong the drug release until 72 h with the enhanced bioavailability in comparison with the ODS solution. The oil suspension of spray-dried microparticles might be an efficient approach for prolongation of the drug effect in the management of nausea and emesis. Graphical abstract.

Base-Promoted Annulation of Amidoximes with Alkynes: Simple Access to 2,4-Disubstituted Imidazoles

An efficient construction of imidazole ring by a Cs₂CO₃-promoted annulation of amidoximes with terminal alkynes in DMSO has been developed. This protocol provides a simple synthetic route with high atom-utilization for the synthesis of 2,4-disubstituted imidazoles in good yields under transition-metal-free and ligand-free conditions. Internal alkynes can also undergo the annulation to give 2,4,5-trisubstituted imidazoles.

Simultaneous quantification of ondansetron and tariquidar in rat and human plasma using a high performance liquid chromatography-ultraviolet method

Ondansetron, a widely used antiemetic agent, is a P-glycoprotein (P-gp) substrate and therefore expression of P-gp at the blood-brain barrier limits its distribution to the central nervous system (CNS), which was observed to be reversed by coadministration with P-gp inhibitors. Tariquidar is a potent and selective third-generation P-gp inhibitor, and coadministration with ondansetron has shown improved ondansetron distribution to the CNS. There is currently no reported bioanalytical method for simultaneously quantifying ondansetron with a third-generation P-gp inhibitor. Therefore, we aimed to develop and validate a method for ondansetron and tariquidar in rat and human plasma samples. A full validation was performed for both ondansetron and tariquidar, and sample stability was tested under various storage conditions. To demonstrate its utility, the method was applied to a preclinical pharmacokinetic study following coadministration of ondansetron and tariquidar in rats. The presented method will be valuable in pharmacokinetic studies of ondansetron and tariquidar in which simultaneous determination may be required. In addition, this is the first report of a bioanalytical method validated for quantification of tariquidar in plasma samples.

5-HT3 Antagonist Ondansetron Increases apoE Secretion by Modulating the LXR-ABCA1 Pathway

Apolipoprotein E (apoE) is linked to the risk for Alzheimer’s disease (AD) and thus has been suggested to be an important therapeutic target. In our drug screening effort, we identified Ondansetron (OS), an FDA-approved 5-HT3 antagonist, as an apoE-modulating drug. OS at low micromolar concentrations significantly increased apoE secretion from immortalized astrocytes and primary astrocytes derived from apoE3 and apoE4-targeted replacement mice without generating cellular toxicity. Other 5-HT3 antagonists also had similar effects as OS, though their effects were milder and required higher concentrations. Antagonists for other 5-HT receptors did not increase apoE secretion. OS also increased mRNA and protein levels of the ATB-binding cassette protein A1 (ABCA1), which is involved in lipidation and secretion of apoE. Accordingly, OS increased high molecular weight apoE. Moreover, the liver X receptor (LXR) and ABCA1 antagonists blocked the OS-induced increase of apoE secretion, indicating that the LXR-ABCA1 pathway is involved in the OS-mediated facilitation of apoE secretion from astrocytes. The effects of OS on apoE and ABCA1 were also observed in human astrocytes derived from induced pluripotent stem cells (iPSC) carrying the APOE ε3/ε3 and APOE ε4/ε4 genotypes. Oral administration of OS at clinically-relevant doses affected apoE levels in the liver, though the effects in the brain were not observed. Collectively, though further studies are needed to probe its effects in vivo, OS could be a potential therapeutic drug for AD by modulating poE metabolism through the LXR-ABCA1 pathway.

Transdermal Delivery of Ondansetron Hydrochloride via Bilosomal Systems: In Vitro, Ex Vivo, and In Vivo Characterization Studies

Ondansetron hydrochloride (OND) is commonly used for management of postoperative and chemotherapeutic-induced nausea and vomiting. It suffers from low bioavailability (60%) and rapid elimination (t_1/2; 3-4 h). The current work aimed to develop OND-loaded bilosomes as a promising transdermal delivery system capable of surmount drug limitations. The variables influencing the development of OND-loaded bilosomes and niosomes (18 systems) via the thin film hydration technique were investigated, including surfactant type (Span®60 or Span®80), surfactant/cholesterol molar ratio (7:0, 7:1, or 7:3), and sodium deoxycholate (SDC) concentration (0, 2.5, or 5%, w/v). The systems were characterized for particle size, polydispersity index, zeta potential, drug entrapment efficiency (EE%), and in vitro permeation. Based on factorial analysis (3²·2¹) and calculations of desirability values, six systems were further subjected to ex vivo permeation through excised rat skin, differential scanning calorimetry (DSC), powder x-ray diffraction (PXRD), and transmission electron microscopy. Histopathological and in vivo permeation studies in rats were conducted on the best achieved system (B6) in comparison to drug solution. Higher desirability values were achieved with Span® 60-based bilosomes, surfactant/cholesterol molar ratio of 7:1, and SDC concentration of 2.5% w/v with respect to small vesicle size, polydispersity index and high zeta potential, EE%, and cumulative drug permeation. OND was dispersed in amorphous state as revealed from DSC and PXRD studies. No marked effect was observed in rat skin following application of B6 system while higher ex vivo and in vivo cumulative permeation profiles were revealed. Bilosomal systems were considered as safe and efficient carriers for the transdermal delivery for OND.

Ondansetron-related hemorrhagic posterior reversible encephalopathy syndrome (PRES) following gastric bypass

Background

Posterior reversible encephalopathy syndrome (PRES) is a clinical-radiographic syndrome formally recognized in 1996, which describes specific changes noted on neuroimaging thought to be related to impaired cerebral blood flow autoregulation and endothelial dysfunction. We report a case of PRES in the setting of increased ingestion of ondansetron; complicated by hemorrhagic transformation and refractory intracranial hypertension. We hypothesize an association of 5-HT₃ antagonism and PRES.

Findings

This is a case study report; with review of previously published literature through PubMed search. We describe the case of a 25 year old man following bariatric surgery who increased his ingestion of ondansetron, taking up to 40 tablets/day due to excessive nausea and vomiting. The patient was hospitalized for progressively more severe headache of 1 week’s duration. Computed tomography (CT) revealed bilateral cerebral edema in the parietal and occipital lobes in the setting of elevated blood pressure (BP). Three days into his admission, following improvement in his BP with oral anti-hypertensive but continued use of the ondansetron, the patient developed near complete blindness. CT head imaging revealed progression of the posterior cerebral edema and intraparenchymal hemorrhage. He was admitted to our ICU and despite supportive treatment, his neurological examination worsened while CT head imaging findings remained stable. Invasive multimodality monitoring revealed elevated intracranial pressure. The patient was aggressively treated and after a prolonged hospitalization and rehabilitation course, made a significant recovery.

Conclusion

This case highlights a very rare potential neurological complication of ondansetron, a commonly used medication. We hypothesize an underlying association between PRES and 5-HT₃ antagonism, via the latter’s potential role in endothelial dysfunction. Prompt recognition and treatment of PRES is essential, in order to prevent secondary cerebral injury and the associated potentially grave consequences.