Ondansetron attenuates cisplatin-induced behavioral and cognitive impairment through downregulation of NOD-like receptor inflammasome pathway.

Cisplatin is an effective and commonly used chemotherapeutic drug; however, its use is accompanied by several adverse effects, including chemobrain. Ondansetron is a 5-HT3 antagonist, commonly used in prophylactic against chemotherapy-induced nausea and vomiting. Moreover, it has been identified as a novel neuroprotective agent in different animal models. However, its protective role against chemotherapy-induced chemobrain has not been investigated. The current study was the first study that explored the potential neuroprotective effect of ondansetron against cisplatin-induced chemobrain in rats. Cisplatin (5 mg/Kg) was injected intraperitoneally, once weekly, for 4 weeks with the daily administration of ondansetron (0.5 and 1 mg/Kg). Compared to the cisplatin-treated group, ondansetron administration showed a significant decrease in the latency time and a significant increase in ambulation, rearing, and grooming frequency in the open field test (OFT). Moreover, a significant improvement in the latency time in the rotarod and passive avoidance tests, following ondansetron administration. In addition, ondansetron treatment increased the percentage of alternation in the Y-maze test. Also, ondansetron showed a remarkable enhancement in the biochemical parameters in the hippocampus. It increased the acetylcholine (Ach) level and decreased the level of the acetylcholine esterase enzyme (AchE). Ondansetron significantly decreased interleukin-1ß (Il-1ß), tumor necrosis factor-alpha (TNF-α), toll-like receptor-4 (TLR-4), NOD-like receptor-3 (NLRP3) inflammasome as well as caspase-1 and caspase-3 levels. Furthermore, ondansetron significantly decreased the levels of copper transporter-1(CTR1) expression in the hippocampus. Collectively, these findings suggest that ondansetron may exhibit a neuroprotective and therapeutic activity against cisplatin-induced chemobrain.

Effect of preoperative ondansetron on postoperative nausea in healthy dogs undergoing laparoscopic gastropexy and castration.

OBJECTIVE: To investigate if preoperative ondansetron reduces postoperative nausea associated with laparoscopic gastropexy and castration in dogs. STUDY DESIGN: Prospective clinical study. ANIMALS: Twenty client-owned, healthy male dogs. METHODS: Dogs were premedicated with dexmedetomidine (2-5 mcg kg-1) and methadone (0.2-0.5 mg kg-1) intramuscularly. General anesthesia was induced with propofol and maintained with an inhalant anesthetic agent. Dogs were randomized into group S (saline 0.1 mL kg-1, intravenously) or group O (ondansetron 0.2 mg kg-1, intravenously). Plasma and serum were collected before premedication and 3 hours postextubation to measure arginine vasopressin (AVP) and cortisol concentrations. Nausea scoring occurred before and 10 minutes after premedication, immediately after extubation, and at 1, 2 and 3 hours postextubation. Data were analyzed by mixed and split-plot anova with Bonferroni adjustment for the number of group comparisons. Significance was set at p < 0.05. RESULTS: Nausea scores increased over time at 1 (p = 0.01) and 2 (p < 0.001) hours postextubation in both groups compared with before premedication. Median nausea score (0-100 mm) for groups S and O before premedication were 2.5 and 0.5 mm, respectively. At 1 and 2 hours postextubation, group S scored 7.5 and 4.0 mm and group O scored 6.0 and 5.0 mm, respectively. No significant differences in nausea scores within or between groups were observed before premedication and 3 hours postextubation. Cortisol concentrations increased significantly 3 hours postextubation in both groups (p < 0.001) compared with before premedication, with no differences between groups. AVP concentrations showed no significant differences within or between groups. CONCLUSIONS AND CLINICAL RELEVANCE: Preoperative intravenous administration of ondansetron (0.2 mg kg-1) did not impact postoperative nausea after laparoscopic gastropexy and castration. Investigation of higher doses of ondansetron on the incidence of postoperative nausea and vomiting in dogs after surgery is warranted.

Associations between ondansetron and the incidence of postoperative nausea and vomiting and food intake in Japanese female undergoing laparoscopic gynecological surgery: a retrospective study.

PURPOSE: Prevention of postoperative nausea and vomiting (PONV) is important to achieve DREAM (drinking, eating, mobilization). Ondansetron inhibits PONV, but its effects on postoperative food intake have not been investigated. This study aimed to examine associations between ondansetron and PONV incidence, and postoperative food intake. METHODS: This retrospective study included adult patients (n = 632) who underwent laparoscopic gynecological surgery at Kyushu University Hospital between January 2017 and June 2023. Outcomes were PONV on the day of surgery, PONV up to the day after surgery, and food intake, which was assessed for breakfast and lunch on the day after surgery. Odds ratios (ORs) for PONV incidence and postoperative no-food intake were calculated between those with and without ondansetron during surgery. Multivariable-adjusted analysis was performed using possible confounding factors for PONV. Synergistic effects of combining ondansetron with dexamethasone or total intravenous anesthesia (TIVA) were assessed. RESULTS: Multivariable-adjusted ORs for PONV on the day of surgery and up to the day after surgery were 0.56 (95% confidence interval, 0.32-0.99, p = 0.04) and 0.52 (0.30-0.93, p = 0.03), respectively, in the ondansetron group (n = 84) compared with the non-ondansetron group (n = 548). In contrast, multivariable-adjusted ORs for no-food intake of breakfast and lunch the day after surgery in the ondansetron group compared with the non-ondansetron group were not significant. Analysis of synergistic effects on PONV showed no significant interaction between ondansetron and dexamethasone or ondansetron and TIVA combinations. CONCLUSION: Ondansetron administration during surgery was significantly associated with decreased PONV risk but was not associated with food intake the day after surgery.

The Incidence of Torsades de Pointes With Perioperative Triple Antiemetic Administration.

BACKGROUND: The safety of triple antiemetic therapy consisting of ondansetron, haloperidol, and a steroid, to surgical patients is unknown. OBJECTIVE: To determine the incidence of torsade de pointes (TdP) or death following perioperative administration of triple antiemetic therapy. METHODS: A retrospective cohort study identified 19,874 patients who received 22,202 doses of triple antiemetics during the 2.5-year time frame from March 4, 2020 to September 7, 2022 for surgical nausea prophylaxis or treatment of nausea. These patients above were cross-matched with an electrocardiogram and adverse outcome database; this identified 226 patients with documentation of a QTc > 450 ms, all ventricular tachycardias including TdP within 48 hours of receiving triple antiemetic therapy, or death within 7 days of receiving ondansetron. RESULTS: There were 3 patients who had documented VT (n = 3), but there were no documented incidents of TdP (n = 0). There were 9 codes called on patients within 48 hours of medication administration, and none of them were due to ventricular arrythmias (n = 0). A total of 11 patients died within 7 days of triple antiemetic therapy. Ten of the 11 deaths were determined to not be from the triple antiemetic. One patient died at home within 24 hours of the procedure of an unknown cause (n = 1). CONCLUSIONS AND RELEVANCE: No episodes of TdP were identified in patients receiving triple antiemetic therapy perioperatively, though the cause of death in 1 patient could not be determined. This suggest that low-dose triple antiemetic therapy is low risk for the development of TdP.

Antiemetic use and chemotherapy induced nausea and vomiting related hospitalization costs after highly or moderately emetogenic chemotherapy.

Aim: Despite numerous available antiemetics, chemotherapy induced nausea and vomiting (CINV) still affects many patients, and CINV related hospitalizations and costs often result. Materials & methods: PrecisionQ analyzed its database to evaluate CINV related hospitalizations and costs following antiemetics use including netupitant/fosnetupitant with palonosetron (NEPA), aprepitant/fosaprepitant with ondansetron (APON) or aprepitant/fosaprepitant with palonosetron (APPA) in patients receiving highly emetogenic chemotherapy or moderately emetogenic chemotherapy. Results: Database analysis identified 15,583 patient records (807 NEPA, 2023 APON, 12,753 APPA) and mean CINV related hospitalization costs were lower across all patients receiving NEPA (US$301) compared with patients receiving APON ($1006, p < 0.0001) or APPA ($321, p < 0.0001). Conclusion: NEPA is associated with lower CINV related hospitalization costs compared with APON and APPA among patients receiving highly emetogenic chemotherapy or moderately emetogenic chemotherapy.

Chemotherapy patients often experience nausea and vomiting that not only has a negative impact on the patient's quality of life but can also result in unplanned hospitalizations with high associated costs. Numerous medications and specific guidelines are available to prevent nausea and vomiting in patients with cancer. Specifically, the combination of two classes of medications (serotonin inhibitors + neurokinin type 1 inhibitors) has been shown to provide the greatest benefit. However, hospitalizations due to nausea and vomiting still occur, and providers require further information to determine the best options for their patients. In this study, the combination of netupitant/fosnetupitant with palonosetron resulted in lower hospitalization costs compared with aprepitant/fosaprepitant with ondansetron or aprepitant/fosaprepitant with palonosetron in chemotherapy patients.

Effects of ondansetron, metoclopramide and granisetron on perioperative nausea and vomiting in patients undergone bariatric surgery: a randomized clinical trial.

INTRODUCTION: Post-operative nausea and vomiting (PONV) is a common problem after sleeve gastrectomy. In recent years, following the increase in the number of such operations, special attention has been paid to preventing PONV. Additionally, several prophylaxis methods have been developed, including enhanced recovery after surgery (ERAS) and preventive antiemetics. Nevertheless, PONV has not been completely eliminated, and the clinicians are trying to reduce the incidence of PONV yet. METHODS: After successful ERAS implementation, patients were divided into five groups, including control and experimental groups. Metoclopramide (MA), ondansetron (OA), granisetron (GA), and a combination of metoclopramide and ondansetron (MO) were used as antiemetics for each group. The frequency of PONV during the first and second days of admission was recorded using a subjective PONV scale. RESULTS: A total of 130 patients were enrolled in this study. The MO group showed a lower incidence of PONV (46.1%) compared to the control group (53.8%) and other groups. Furthermore, the MO group did not require rescue antiemetics, however, one-third of control cases used rescue antiemetics (0 vs. 34%). CONCLUSION: Using the combination of metoclopramide and ondansetron is recommended as the antiemetic regimen for the reduction of PONV after sleeve gastrectomy. This combination is more helpful when implemented alongside ERAS protocols.

Effects of ondansetron treatment on outcomes of critically ill patients with myocardial infarction partly through its anti-inflammatory activity.

Background: Patients with myocardial infarction (MI) in intensive care units (ICU) are at high risk of death. Whether treatment with ondansetron (OND) at an early stage plays a protective role in critically ill patients with MI and its underlying mechanism remains unclear. Methods: A total of 4486 patients with MI were enrolled in the study cohort from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database and divided into OND-medication groups or not. Propensity score matching (PSM) and regression analysis were performed to investigate the effect of OND on patients, accompanied by sensitivity analysis to evaluate the robustness of the results. Integrated with causal mediation analysis (CMA), we investigated the potential causal pathway mediated by the palate-to-lymphocyte ratio (PLR) between early OND treatment and clinical outcomes. Results: Among patients with MI, 976 of them were treated with OND at the early stage while 3510 patients were not. The all-cause in-hospital mortality rate was significantly lower in the OND-medication group (5.6% vs 7.7%), accompanied by lower 28-day mortality (7.8% vs 11.3%) and 90-day mortality (9.2% vs 13.1%) rates. PSM analysis further confirmed the results for in-hospital mortality (5.7% vs 8.0%), 28-day mortality (7.8% vs 10.8%), and 90-day mortality (9.2% vs 12.5%). After adjusting for confounders, multivariate logistic regression analysis revealed that OND was associated with decreased in-hospital mortality (OR = 0.67, 95% CI: 0.49-0.91), and Cox regression confirmed the results for 28-day mortality and 90-day mortality with HR = 0.71 and 0.73, respectively. Most importantly, CMA demonstrated that the protective effect of OND on patients with MI was mediated by its anti-inflammatory effect through the regulation of PLR. Conclusion: Early use of OND in critically ill patients with MI may exert protective effects by reducing in-hospital mortality and 28- and 90-day mortality. The beneficial effects of OND on these patients were exerted through anti-inflammatory effects, at least in part.

QT prolongation, torsades des pointes, and cardiac arrest after 4 mg of IV ondansetron.

Ondansetron is a commonly used antiemetic in the emergency department despite a 2011 FDA warning regarding dose-related QTc prolongation and torsades des pointes (TdP). Cases of TdP from small ondansetron doses administered in the emergency department are lacking. A 41-year-old-woman with alcohol use disorder on no medications or supplements presented to an emergency department with one day of nausea, vomiting, and epigastric pain. Examination revealed a pulse of 77 beats/min and epigastric tenderness. The patient received 4 mg IV ondansetron, 30 mg IV ketorolac, and was placed on cardiac monitoring. ECG obtained one minute after ondansetron demonstrated premature ventricular contractions with QTc = 653 ms. Thirteen minutes after receiving ondansetron she suffered TdP and cardiac arrest. She received immediate CPR and IV epinephrine with successful defibrillation at one minute. She then received IV magnesium. Post-arrest ECGs demonstrated persistent QTc prolongation immediately and at three hours post-arrest. Laboratory studies, drawn prior to arrest, demonstrated hypokalemia (3.2 mEq/L), hypomagnesemia (1.3 mg/dL), and elevated lipase (4918 IU/L). She received no additional QT-prolonging agents. Transthoracic echocardiogram and troponins were normal; ECG intervals completely normalized within 12 h and she was discharged neurologically intact. The patient returned 18 months later with recurrent pancreatitis and similar electrolyte abnormalities; QT-prolonging drugs were avoided at that time and her course was uncomplicated. QT prolongation with subsequent torsades des pointes and cardiac arrest may occur in high-risk patients receiving small doses of ondansetron. Further studies are warranted to determine the safest antiemetic for use in the emergency department.

Assessing the impact of aprepitant and ondansetron on postoperative nausea and vomiting in orthognathic surgeries: a randomized controlled trial.

BACKGROUND: Postoperative nausea and vomiting (PONV) is a common side effect associated with general anesthesia. Both ondansetron and aprepitant been effectively used to prevent PONV. However, there is a disagreement of opinions regarding the superiority of these two drugs. This study aims to compare the efficacy of aprepitant with ondansetron in preventing PONV following orthognathic surgeries. METHODS: In this double-blinded clinical trial, 80 patients scheduled for orthognathic surgery at Imam Hossein Hospital, Tehran, Iran, were randomly assigned to two groups. A standardized anesthesia protocol was used for all patients. The first group received a placebo capsule administered one hour before the surgical procedure along with 4 mg (2 ml) of ondansetron intravenously after anesthesia induction. The second group was given 80 mg aprepitant capsules one hour before the surgery, followed by an injection of 2 ml intravenous distilled water after anesthesia induction. The occurrence and severity of PONV, the amount of rescue medication required, and the complete response of patients assessed within 24 h after the surgery. RESULTS: There were no significant differences in demographic data between the two groups. Patients in the aprepitant group had a significantly lower incidence and severity of nausea (2.5% versus 27.5%), vomiting (5% versus 25%), and required fewer rescue medications (7.5% versus 62.5%) compared to the ondansetron group. Additionally, the aprepitant group showed a higher complete response rate (90% versus 67.5%) in the 0-2 and 12-24 postoperative hours. CONCLUSION: According to the findings of this study, aprepitant has demonstrated a greater efficacy in preventing PONV following orthognathic surgery, when compared to ondansetron. TRIAL REGISTRATION: Iranian Registry of Clinical Trials (IRCT code: IRCT20211205053279N3), date of registration: 16/12/2022.

A meta-analysis of randomized controlled trials: efficiency and safety of ondansetron in preventing post-anesthesia shivering during cesarean section.

OBJECTIVE: Although ondansetron was considered to prevent post-anesthesia shivering during cesarean section, its efficiency remained controversial. Our review was conducted to estimate the efficiency and safety of ondansetron in preventing post-anesthesia shivering during cesarean section. METHODS: The literature were searched from their inception to October 2020 without restriction of language. All randomized controlled trials investigating the efficacy of ondansetron versus placebo in preventing shivering during cesarean section under neuraxial anesthesia were included. The meta-analysis was conducted using Stata software. RESULTS: Eleven randomized controlled studies with a total of 748 individuals were finally included in our meta-analysis. Our results manifested that intravenous ondansetron compared with intravenous placebo significantly reduced the incidence of post-anesthesia shivering (PAS) (RR 0.53, 95% CI 0.14-0.68). Subgroup analysis according to doses of ondansetron indicated that the efficacy of 4 mg doses of ondansetron (RR 0.37, 95% CI 0.21-0.64) is equivalent to that of 8 mg doses of ondansetron (RR 0.61, 95% CI 0.47-0.81) in preventing PAS. In addition, the intravenous ondansetron led to a lower incidence of hypotension than intravenous placebo (OR 0.47, 95% CI 0.32-0.70). We could not demonstrate differences in the incidence of bradycardia between intravenous ondansetron and intravenous placebo. CONCLUSION: Our results found that intravenous ondansetron was effective in preventing shivering during cesarean section under neuraxial anesthesia, and had an advantage in reducing the incidence of hypotension compared with intravenous placebo.

Ondansetron Safety Regarding Prolong QTc for Children with Head Trauma.

BACKGROUND: There have been recent reports of increased QT interval after head trauma in concussed athletes and adult patients. Ondansetron, which is widely used in treatment of nausea and vomiting symptoms in head injuries, was issued a safety warning from the U.S. Food and Drug Administration regarding QT prolongation and risk of fatal dysrhythmias. OBJECTIVE: The purpose of this study was to evaluate the safety of ondansetron regarding QT prolongation for patients experiencing nausea or vomiting after head trauma. METHODS: Patients aged 1-20 years presenting to a pediatric emergency department with head trauma and who required a dose of ondansetron for nausea or vomiting were enrolled in the study. Patients received a baseline 12-lead electrocardiogram (ECG) prior to administration of either oral or IV ondansetron. A second post-ondansetron 12-lead ECG was performed after administration of ondansetron. All ECGs were reviewed and the QTc calculated manually by a board-certified pediatric cardiologist. RESULTS: Forty-two patients met enrollment criteria. Five patients received IV ondansetron and 37 received oral ondansetron. Mean QTc pre ondansetron was 387.5 ms and mean QTc post ondansetron was 400.9 ms (p = 0.120). We found no statistically significant difference in other ECG parameters pre and post ondansetron. CONCLUSIONS: Ondansetron is safe in regard to QTc prolongation in patients with head trauma. Based on this research, ondansetron should continue to be used for the treatment of nausea and vomiting in emergency department patients who present with head injury.

5-HT3 Receptors on Mitochondria Influence Mitochondrial Function.

The 5-hydroxytryptamine 3 (5-HT3) receptor belongs to the pentameric ligand-gated cation channel superfamily. Humans have five different 5-HT3 receptor subunits: A to E. The 5-HT3 receptors are located on the cell membrane, but a previous study suggested that mitochondria could also contain A subunits. In this article, we explored the distribution of 5-HT3 receptor subunits in intracellular and cell-free mitochondria. Organelle prediction software supported the localization of the A and E subunits on the inner membrane of the mitochondria. We transiently transfected HEK293T cells that do not natively express the 5-HT3 receptor with an epitope and fluorescent protein-tagged 5HT3A and 5HT3E subunits. Fluorescence microscopy and cell fractionation indicated that both subunits, A and E, localized to the mitochondria, while transmission electron microscopy revealed the location of the subunits on the mitochondrial inner membrane, where they could form heteromeric complexes. Cell-free mitochondria isolated from cell culture media colocalized with the fluorescent signal for A subunits. The presence of A and E subunits influenced changes in the membrane potential and mitochondrial oxygen consumption rates upon exposure to serotonin; this was inhibited by pre-treatment with ondansetron. Therefore, it is likely that the 5-HT3 receptors present on mitochondria directly impact mitochondrial function and that this may have therapeutic implications.

Association between early ondansetron administration and in-hospital mortality in critically ill patients: analysis of the MIMIC-IV database.

BACKGROUND: While ondansetron (OND) is widespread availability, the contribution of OND to improve patient outcomes among intensive care unit (ICU) patients has not been examined. This study aimed to illustrate the association between early OND use and in-hospital mortality in critically ill patients and investigate whether this association differed according to OND dose. METHODS: The MIMIC-IV database was employed to identify patients who had and had not received OND. Statistical approaches included multivariate logistic regression, propensity score matching (PSM), and propensity score-based inverse probability of treatment weighting (IPTW) models to ensure the robustness of our findings. RESULTS: In total, 51,342 ICU patients were included. A significant benefit in terms of in-hospital mortality was observed in the OND patients compared to the non-OND group in the early stage [odds ratio (OR) = 0.75, 95% CI 0.63-0.89, p < 0.001]. In the circulatory system group, the early OND administration was associated with improved in-hospital mortality in ICU patients (OR 0.48, 95% CI 0.34-0.66; P < 0.001). The risk of in-hospital mortality was also lower in early OND users than in non-OND users both in the medical admission group and the surgical ICU admission group, and ORs were 0.57 (95% CI 0.42-0.76; P < 0.001) and 0.79 (95% CI 0.62-0.91; P < 0.001), respectively. A positive role of daily low- and moderate-dose OND treatment in early-stage was showed on the in-hospital mortality in PSM cohort, and the ORs were 0.75 (95% CI 0.62-0.90; P < 0.001) and 0.63 (95% CI 0.43-0.91; P < 0.001), respectively. The relationship between the daily low- and moderate-dose of OND and in-hospital mortality was also significant in ICU patients with cardiovascular diseases, and ORs were 0.51(95% CI 0.36-0.73; P < 0.001), and 0.26(95% CI 0.11-0.65; P < 0.001), respectively. Daily low-to-moderate dose of OND was also associated with in-hospital mortality in ICU entire cohort. CONCLUSIONS: Early OND use is closely associated with lower in-hospital mortality in ICU patients. Daily low-to-moderate dose of OND application is protective against in-hospital mortality. This association is more evident in the circulatory system group.

A randomized, double-blind, placebo-controlled, pharmacogenetic study of ondansetron for treating alcohol use disorder.

BACKGROUND: In a previous study, ondansetron, a serotonin 5-HT3 receptor antagonist, reduced drinking intensity (drinks/drinking day [DPDD]) among European-ancestry (EA) participants with moderate-to-severe alcohol use disorder (AUD) and variants in genes encoding the serotonin transporter (SLC6A4) and 5-HT3A (HTR3A), and 5-HT3B (HTR3B) receptors. We tested whether (1) ondansetron reduces DPDD among individuals of either European or African ancestry (AA), and (2) that reductions in DPDD are greatest among ondansetron-treated individuals with population-specific combinations of genotypes at SLC6A4, HTR3A, and HTR3B. METHODS: In this 16-week, double-blind, placebo-controlled, parallel-group clinical trial, adults with AUD were randomized to receive low-dose oral ondansetron (0.33 mg twice daily) or placebo stratified by "responsive" versus "nonresponsive" genotype defined using population-specific genotypes at the three genetic loci. Generalized estimating equation regression models and a modified intent-to-treat analysis were used to compare the treatment groups on the primary outcome-DPDD-and two secondary outcomes-heavy drinking days per week [HDD] and drinks per day [DPD] across the 16 weeks of treatment. RESULTS: Of 296 prospective participants screened, 95 (58 EA and 37 AA) were randomized and received at least one dose of study medication. In the modified intent-to-treat analysis, the ondansetron group averaged 0.40 more DPDD (p = 0.51), 1.35 times as many HDD (p = 0.16), and 1.06 times as many DPD (p = 0.59) as the placebo group. There were no significant interactions with genotype. There were no study-related serious adverse events (AEs) and similar proportions of participants in the two treatment groups experienced AEs across organ systems. CONCLUSIONS: We found no evidence that low-dose oral ondansetron is beneficial in the treatment of AUD, irrespective of genotype, thus failing to confirm prior study findings. However, the study was underpowered to identify medication by genotype interactions.

Mediators of neutrophil-lymphocyte ratio in the relationship between ondansetron pre-treatment and the mortality of ICU patients on mechanical ventilation: Causal mediation analysis from the MIMIC-IV database.

AIMS: The mortality of critically ill patients undergoing mechanical ventilation (MV) is high and few strategies are available. We explored the relationship between ondansetron pre-treatment, the neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR), and mortality of ventilated patients in the intensive care unit. METHODS: We developed a retrospective cohort study that involved patients undergoing MV in the Multiparameter Intelligent Monitoring in Intensive Care IV (MIMIC-IV) database. Causal mediation analysis was conducted to assess the relationship of ondansetron use and mortality and to explore the potential causal pathway mediated by the NLR or PLR. The primary outcome was 28-day mortality. RESULTS: A total of 17 927 eligible patients took part in the study (5665 had taken ondansetron before MV initiation and 12 262 patients had not). The odds ratio (OR) for 28-day mortality for ondansetron use uncorrelated with the mediator (NLR, PLR) was 0.72 (95% confidence interval [CI] = 0.64-0.81, P < .001). Ondansetron was also associated with a reduction in 28-day mortality after controlling for the mediator of NLR (OR = 0.98, 95% CI = 0.97-0.99, P < .01). For the indirect effect, the NLR could explain 13.47% (95% CI = 8.59-20.54%, P < .01) of the impact of ondansetron use on 28-day mortality. The proportion mediated increased to 21.50% (95% CI = 12.36-47.44%, P < .01) for 90-day mortality. Adjusted mediation analysis revealed no suggestion of a causal mediation pathway for this effect by the PLR (P = .12). CONCLUSIONS: NLR may play substantial roles in the relationship between ondansetron pre-treatment before initiation of mechanical ventilation and the reduction of death risk in ventilated patients.

Ondansetron use in nausea and vomiting during pregnancy: A descriptive analysis of prescription patterns and patient characteristics in UK general practice.

AIMS: The objective of this study was to describe ondansetron drug utilization patterns during pregnancy to treat nausea and vomiting in pregnancy (NVP). Moreover, we aimed to describe the maternal factors associated with NVP and antiemetic use. METHODS: The data consist of pregnancies with a live birth(s) within an IMRD-UK registered GP practice. Descriptive statistics were used to investigate patterns of ondansetron use in pregnancy and to describe maternal characteristics associated with NVP and antiemetic drug utilization. We differentiate first- from second-line use during pregnancy using antiemetic prescription pathways. RESULTS: The dataset included 733 633 recorded complete pregnancies from 2005 to 2019. NVP diagnosis and ondansetron prescription prevalence increased from 2.7% and 0.1% in 2005 to 4.8% and 2.5% in 2019 respectively. Over the period 2015-2019, the most common oral daily dosages were 4 mg/d (8.5%), 8 mg/d (37.1%), 12 mg/d (37.5%) and between 16 and 24 mg/d (16.9%). Prescription of ondansetron was initiated during the first trimester of pregnancy in 40% of the cases and was moderately used as a first-line therapy (2.8%), but preferred choice of second-line therapy. Women with mental health disorders, asthma and/or prescribed folic acid were more likely to experience NVP and use antiemetics in pregnancy than their counterparts. CONCLUSION: This study confirms that ondansetron is increasingly used off-label to treat NVP during pregnancy, also in the first trimester and before other prescription antiemetics have been prescribed. Several maternal comorbidities and folic acid use were more common among women experiencing NVP and using antiemetics, including ondansetron.

Kidney and Mortality Outcomes Associated with Ondansetron in Critically Ill Patients.

Background: Ondansetron is a preferred anti-emetic in critical care to treat nausea and vomiting, and has historically been considered a largely safe option. A recent pharmacoepidemiology study reported that ondansetron may be associated with an increased risk for acute kidney injury (AKI). Methods: We interrogated the High-Density Intensive Care (HiDenIC-15) database containing intensive care data for 13 hospitals across Western Pennsylvania between Oct 2008-Dec 2014. AKI was defined using the Kidney Disease, Improving Global Outcomes 2012 guidelines. Ondansetron use was considered as receiving any form of ondansetron within 24 h of admission. The subsequent 48 h (hours 25-72 after admission) were analyzed for outcomes. Primary outcome was development of AKI; secondary outcomes included 90-day mortality and time to AKI. Propensity-matched, multivariate logistic regression was applied for both outcomes. Comparator groups were metoclopramide and prochlorperazine using the same exposure criteria. Results:AKI occurred in 965 (5.6%), 12 (3.0%), and 61 (6.5%) patients receiving ondansetron, prochlorperazine, and metoclopramide, respectively. In the adjusted analysis, no anti-emetic was associated with a significant change in the odds of developing AKI. Ondansetron was associated with a 5.48% decrease (CI -6.17--4.79) in death within 90 days of ICU-admission, which was independent of AKI status; an effect not seen with other anti-emetics. Anti-emetic usage was not associated with a change in the time to first AKI. Conclusion:Anti-emetic usage did not alter AKI risk. Ondansetron was associated with a significant decrease in 90-day mortality that was not seen by other anti-emetics, which requires further exploration.

Pharmacogenetic and clinical predictors of ondansetron failure in a diverse pediatric oncology population.

PURPOSE: Chemotherapy-induced nausea and vomiting (CINV) is a frequently seen burdensome adverse event of cancer therapy. The 5-HT3 receptor antagonist ondansetron has improved the rates of CINV but, unfortunately, up to 30% of patients do not obtain satisfactory control. This study examined whether genetic variations in a relevant drug-metabolizing enzyme (CYP2D6), transporter (ABCB1), or receptor (5-HT3) were associated with ondansetron failure. METHODS: DNA was extracted from blood and used to genotype: ABCB1 (3435C > T (rs1045642) and G2677A/T (rs2032582)), 5-HT3RB (rs3758987 T > C and rs45460698 (delAAG/dupAAG)), and CYP2D6 variants. Ondansetron failure was determined by review of the medical records and by patient-reported outcomes (PROs). RESULTS: One hundred twenty-nine patients were approached; 103 consented. Participants were less than 1 to 33 years (mean 6.85). A total of 39.8% was female, 58.3% was White (22.3% Black, 19.4% other), and 24.3% was Hispanic. A majority had leukemia or lymphoma, and 41 (39.8%) met the definition of ondansetron failure. Of variants tested, rs45460698 independently showed a significant difference in risk of ondansetron failure between a mutant (any deletion) and normal allele (p = 0.0281, OR 2.67). Age and BMI were both predictive of ondansetron failure (age > 12 (OR 1.12, p = 0.0012) and higher BMI (OR 1.13, p = 0.0119)). In multivariate analysis, age > 12 was highly predictive of ondansetron failure (OR 7.108, p = 0.0008). rs45460698 was predictive when combined with an increased nausea phenotype variant of rs1045642 (OR 3.45, p = 0.0426). CONCLUSION: Select phenotypes of 5-HT3RB and ABCB1, age, and potentially BMI can help predict increased risk for CINV in a diverse pediatric oncology population.

The evolving epidemiology of acute gastroenteritis in hospitalized children in Italy.

Few data are available on the prevalence and features of acute gastroenteritis (AGE) in hospitalized children in Italy, where specific rotavirus vaccines were introduced into the national vaccination plan in 2017. To evaluate vaccination effects on AGE epidemiology, we analysed data from children aged ≤ 18 years admitted for AGE at the University Hospital of Pisa in 2019, comparing them with those recorded in 2012. Demographical, clinical, diagnostic, and treatment data were collected reviewing medical records and were therefore compared. In 2019 and 2012, 86 (median age 2.5 years [IQR 1.4-5.9]) and 85 children (median age 2.3 years [IQR 1.3-5.1]) were respectively admitted with AGE. The most common symptoms were diarrhoea and vomiting; decreased skin turgor was more frequent in 2019 (54% and 34% respectively, p = 0.01). Viral infections were more common than bacterial ones; in 2019, a decrease in rotavirus infections (67% and 22%, p = 0.003) and an increase in adenovirus infections (50% and 10%, p = 0.002) and in the number of patients with negative stool testing (58% and 39%, p = 0.04) were found.Conclusions: Viral infections are the leading cause of AGE in hospitalized children in Italy. The introduction of rotavirus vaccines did not reduce the number of hospitalizations per year. Adenovirus and other non-routinely screened viruses may be undergoing a selection process making them common causative agents for AGE. What is Known: • Rotavirus is the leading cause of acute severe gastroenteritis in children worldwide, especially < 5 years of age. • The introduction of specific vaccines may be changing its epidemiology. • Few data are available on acute gastroenteritis in hospitalized children in Italy. What is New: • Viral infections are the leading cause of acute gastroenteritis in hospitalized children in Italy. • Specific vaccines are reducing rotavirus infections, but adenovirus and other non-routinely screened viruses may be undergoing a selection process making them common causative agents for gastroenteritis.

Antiemetic treatment of hyperemesis gravidarum in 1,064 Norwegian women and the impact of European warning on metoclopramide: a retrospective cohort study 2002-2019.

BACKGROUND: Women suffering from severe nausea and vomiting during pregnancy, hyperemesis gravidarum, have poor quality of life and increased risk of potentially fatal maternal and fetal complications. There is increasing and reassuring knowledge about safety of antiemetics in pregnancy. In 2013, the European Medical Agency (EMA) issued a warning on metoclopramide limiting treatment to maximum five days. Metoclopramide was the most used antiemetic in pregnancy at the time the warning was implemented in the Norwegian hyperemesis guidelines (2014). We aimed at describing changes in the treatment of hyperemesis over time, including changes associated with the EMA warning. METHODS: Retrospective chart review of all women hospitalized for hyperemesis gravidarum with metabolic disturbances between 01/Jan/2002 and 31/Dec/2019 at a university hospital serving nearly 10% of the pregnant population in Norway. Time-series analysis described changes over time and interrupted time series analysis quantified changes in treatment and clinical outcomes related to the EMA warning. RESULTS: In total, 1,064 women (1.2% of the birthing population) were included. The use of meclizine, prochlorperazine, and ondansetron increased during 2002-2019. This led to a yearly increase in the percentage of women using any antiemetic of 1.5% (95%CI 0.6; 2.4) pre-hospital, 0.6% (95%CI 0.2; 1.1) during hospitalization, and 2.6% (95%CI 1.3; 3.8) at discharge. Overall, only 50% of the women received antiemetics pre-hospital. Following the EMA warning, prehospital use of metoclopramide dropped by 30% (95%CI 25; 36), while use of any antiemetic pre-hospital dropped by 20% (95%CI 5.7; 34). In timely association, we observed a decrease in gestational age (-3.8 days, 98.75%CI 0.6; 7.1) at first admission, as well as indication of increased rate of termination of pregnancy with an absolute increase of 4.8% (98.75%CI 0.9; 8.7) in 2014. CONCLUSION: During 2002-2019, the overall use of antiemetics in treatment of hyperemesis increased. The EMA-warning on metoclopramide in 2013 temporarily limited pre-hospital antiemetic provision associated with hospitalization at lower gestational length and indication of an increase in termination of pregnancy.