Use Of APAP Research Articles

Association between acetaminophen administration and outcomes in critically ill patients with gout and hypertension.

Acetaminophen is a commonly used medication, yet its recommendation for patients with comorbid conditions of gout and hypertension is contradictory, and the impact of its usage on clinical outcomes in real-world practical settings remains uncertain. The aim of this study was to investigate the association between acetaminophen administration and clinical outcomes in critically ill patients with gout and hypertension, utilizing real-world data. A retrospective cohort study was conducted based on the MIMIC-IV (Medical Information Mart in Intensive Care-IV) database. Adult critically ill patients with gout and hypertension were included in the analysis. The exposure was acetaminophen use during ICU stay. The primary outcome was in-hospital mortality. The secondary endpoints were frequent hospitalization, 30-day, and 60-day all-cause mortality, and incidence of hypertensive emergencies. Propensity score matching (PSM) was conducted at a 1:1 ratio. Multivariable analyses were used to adjust for confounders. The pre-matched and propensity score-matched cohorts included 2448 and 1012 patients, respectively. In the PSM analysis, in-hospital mortality was 9.7% (49/506) in the acetaminophen use group and 12.1% (61/506) in the no use group. Acetaminophen use was associated with a decrease in-hospital mortality (hazard ratio [HR], 0.62; 95% CI, 0.41-0.92; P = 0.018). In terms of secondary endpoints, after PSM, there was no statistically significant difference for both 30-day and 60-day all-cause mortality reductions in the acetaminophen use group, and HRs were 0.78 (95% CI 0.55-1.11; P = 0.175), and 0.75 (95% CI 0.55-1.02; P = 0.069), respectively. According to the analysis of dosage and treatment group, the use of APAP within the dosage range of 2-4g and within 3-5days of treatment significantly reduced the mortality rate of the entire cohort and PSM cohort, with statistical differences. Subgroup analysis demonstrated that lower in-hospital mortality was consistent across different baselines (age, gender, BMI, liver disease, and renal disease), with no interactions in all subgroups (interaction p-values >0.05), thereby affirming the robustness and reliability of the findings. Acetaminophen use was associated with lower in-hospital mortality in critically ill patients with gout and hypertension. Prospective studies are needed to verify this finding.

Association of Acetaminophen (Paracetamol) Use With Severity and Outcomes in Patients With Viral Hepatitis-Associated Acute Liver Failure.

Acute viral hepatitis (AVH) comprises 11% of acute liver failure (ALF) in North America while acetaminophen (APAP) toxicity represents 46%. The use of APAP to treat prodromal hepatitis symptoms is common. It is unknown if concurrent APAP use impacts liver injury in AVH-induced ALF. In this prospective, multicenter cohort study, 356 patients meeting criteria for AVH including hepatitis A, B, Epstein-Barr virus, and herpes simplex virus, all leading to ALF (hepatic encephalopathy after acute illness, international normalized ratio ≥1.5), or acute liver injury (acute liver injury, international normalized ratio >2.0, no hepatic encephalopathy) were reviewed for evidence of APAP use: APAP ingestion history or measurement of serum APAP level or APAP-CYS adducts, a specific biomarker released into blood with APAP injury. Patients were grouped by APAP exposure level, from high (measurable APAP levels or toxic APAP-CYS), medium (therapeutic APAP-CYS), low (history of APAP ingestion only and/or barely detectable APAP-CYS), or no exposure recorded. Two hundred five of 356 patients (57.5%) with AVH-ALF had evidence of APAP use: 87 out of 356 (24%) demonstrated high or medium exposures. The aminotransferase and bilirubin levels of high/medium group resembled a mixed APAP-viral injury. Mortality was the highest (51.6%, 21.4%, 28.8%, and 30.5%), and transplant-free survival was the lowest (22.6%, 44.6%, 41.5%, and 40.4%) in the high exposure group compared with medium, low, and no exposure groups. However, the specific comparisons of mortality and transplant-free survival between the high exposure and no exposure groups were not statistically different even after adjusting for baseline patient characteristics differences. APAP use in AVH-ALF is common and may negatively impact outcomes compared with little or no APAP exposure. Prospective studies of the safest and effective dose of APAP to use in patients with AVH are needed.

Drug-drug interaction assessment based on a large-scale spontaneous reporting system for hepato- and renal-toxicity, and thrombocytopenia with concomitant low-dose methotrexate and analgesics use

BackgroundMethotrexate (MTX) is the cornerstone of rheumatoid arthritis (RA) treatment and is highly effective with low-dose intermittent administration. MTX is occasionally used in combination with non-steroidal anti-inflammatory drugs (NSAIDs) and acetaminophen (APAP)/paracetamol for pain or inflammation control. With MTX treatment, the side effects, such as hepatotoxicity, renal failure, and myelosuppression should be considered. These are also seen with analgesics treatment.MethodsWe used a large spontaneously reported adverse event database (FAERS [JAPIC AERS]) to analyze whether the reporting of adverse events increased upon MTX and analgesic therapy in patients with RA.ResultsAfter identifying RA cases, the crude reporting odds ratios (cRORs) for hepatotoxicity, renal failure, and thrombocytopenia associated with the use of MTX, APAP, or NSAIDs were calculated by disproportionality analysis, which revealed significantly higher cRORs for these events. No analgesics showed consistent positive signals for drug-drug interaction (DDI) with concomitant low-dose MTX analyzed using four algorithms for DDI interaction (the Ω shrinkage measure, additive or multiplicative, and combination risk ratio models). However, in renal failure and thrombocytopenia, loxoprofen (Ω025 = 0.08) and piroxicam (Ω025 = 0.46), and ibuprofen (Ω025 = 0.74) and ketorolac (Ω025 = 3.52), respectively, showed positive signals in the Ω shrinkage measure model, and no consistency was found among adverse events or NSAIDs.ConclusionsStudies using spontaneous reporting systems have limitations such as reporting bias or lack of patient background; however, the results of our comprehensive analysis support the results of previous clinical or epidemiological studies. This study also demonstrated the usefulness of FAERS for DDI assessment.

Effects of Acetaminophen Exposure on Outcomes of Patients Receiving Immune Checkpoint Inhibitors for Advanced Non-Small-Cell Lung Cancer: A Propensity Score-Matched Analysis.

(1) Background: Several studies have investigated potential interactions between immune checkpoint inhibitors (ICIs) and commonly prescribed medications. Although acetaminophen (APAP) has not been considered susceptible to interaction with ICIs, recent research has shown that detectable plasma levels of this drug can hinder the efficacy of PD-1/PD-L1 blockade therapies. A reliable assessment of the potential interaction between APAP and ICIs in advanced non-small cell lung cancer (NSCLC) patients would be worthwhile since it is often prescribed in this condition. We sought to evaluate the impact of the concomitant use of APAP in patients with advanced NSCLC on PD-1/PD-L1 blockade using real-world evidence. (2) Methods: This study included consecutive patients with histologically proven stage IV NSCLC who underwent first-line therapy with pembrolizumab as a single agent or in combination with platinum-based chemotherapy, or second-line therapy with pembrolizumab, nivolumab, or atezolizumab. The intensity of APAP exposure was classified as low (therapeutic intake lasting less than 24 h or a cumulative intake lower than 60 doses of 1000 mg) or high (therapeutic intake lasting more than 24 h or a total intake exceeding 60 doses of 1000 mg). The favorable outcome of anti-PD-1/PD-L1 therapies was defined by durable clinical benefit (DCB). Progression-free survival (PFS) and overall survival (OS) were relevant to our efficacy analysis. Propensity score matching (PSM) methods were applied to adjust for differences between the APAP exposure subgroups. (3) Results: Over the course of April 2018 to October 2022, 80 patients were treated with first-line pembrolizumab either as single-agent therapy or in combination with platinum-based chemotherapy. During the period from June 2015 to November 2022, 145 patients were given anti-PD-1/PD-L1 blockade therapy as second-line treatment. Subsequent efficacy analyses relied on adjusted PSM populations in both treatment settings. Multivariate testing revealed that only the level of APAP and corticosteroid intake had an independent effect on DCB in both treatment lines. Multivariate Cox regression analysis confirmed high exposure to APAP and immunosuppressive corticosteroid therapy as independent predictors of shorter PFS and OS in both treatment settings. (4) Conclusions: Our findings would strengthen the available evidence that concomitant intake of APAP blunts the efficacy of ICIs in patients with advanced NSCLC. The detrimental effects appear to depend on the cumulative dose and duration of exposure to APAP. The inherent shortcomings of the current research warrant confirmation in larger independent series.

Opioid sparing effects of intravenous and oral acetaminophen in hip fracture patients: A population-based study

Study objectiveAcetaminophen (APAP) and intravenous acetaminophen (IVAPAP) has been proposed as a part of many opioid-sparing multimodal analgesic pathways. The aim of this analysis was to compare the effectiveness of IVAPAP with oral APAP on opioid utilization and opioid-related adverse effects. DesignRetrospective study of population-based database. PatientsThe Premier Healthcare database was queried patients undergoing surgery for a primary diagnosis of hip fracture from 2011 to 2019 yielding 245,976 patients. Primary exposure was use of IVAPAP or oral APAP on the day of surgery. InterventionsNone. MeasurementsThe primary outcome of interest was opioid utilization over the hospital stay, secondary outcomes included opioid-related adverse effects, length, and costs of hospital stay. Mixed effect models measured the association of IVPAP and APAP and outcomes. Main resultsIn the study population 30.67% (75,445) received at least 1 dose of IVAPAP on the day of surgery. Upon adjusting for relevant covariates, patients who received IVPAP on the day of surgery had slightly higher opioid use standardized by length of hospital stay (2.8% CI: 2%, 3.6%; p < .001), higher hospital cost (2.7% CI: 2.1%, 3.4%), and higher odds of naloxone use (1.18, CI: 1.1, 1.27; p < .001) when compared with patients who received oral APAP. ConclusionsIn this population, IVAPAP use on the day of surgery failed to reduce opioid use or associated opioid related adverse effects when compared with oral APAP. IVAPAP was associated with increased overall costs, opioid requirements, and naloxone use. These results do not support the use of IV over oral APAP routinely for hip fracture surgery patients.

Caveolin-1 alleviates acetaminophen-induced vascular oxidative stress and inflammation in non-alcoholic fatty liver disease

Acetaminophen (APAP) is one of the most widely used drugs in the world. The literature shows that excessive or long-term use of APAP can lead to increased cardiovascular dysfunction. An acute increase in angiotensin Ⅱ (Ang Ⅱ) caused by APAP use in fatty liver disease may increase the risk and severity of vascular injury. However, the underlying mechanism remains unclear. Caveolin-1 (CAV1) is a broad-spectrum kinase inhibitor that significantly determines endothelial function. This study aimed to observe the effects of APAP on the vasculature in non-alcoholic fatty liver disease (NAFLD) and to determine whether CAV1 could alleviate vascular oxidative stress and inflammation by targeting Ang Ⅱ or its downstream pathways. In this study, 7-week-old C57BL/6 male mice (18–20 g) were administered APAP by gavage after eight weeks of a high-fat diet. Any resulting vascular oxidative stress and inflammation were assessed. Levels of Ang Ⅱ, CAV1, and other related proteins were measured using ELISA and western blotting. In APAP-treated NAFLD mice, CAV1 expression was downregulated and Ang Ⅱ expression was upregulated compared to normal APAP-treated mice. In vitro, HUVECs were incubated with Ang Ⅱ (300 nM) for 48 h. Overexpression of CAV1 in HUVECs attenuated Ang Ⅱ-induced oxidative stress and inflammation and downregulated the expression of Protein kinase C (PKC) and p-P38/P38. After intervention with CAV1-siRNA, immunofluorescence results showed that the fluorescence intensity of PKC on mitochondria was further increased, and flow cytometry results showed that the mitochondrial membrane potential increased. PKC inhibitors alleviated Ang Ⅱ-induced endothelial injury. In conclusion, our findings confirmed that CAV1 exerts a protective effect against vascular injury by inhibiting oxidative stress and inflammation through the PKC/MAPK pathway. Therefore, restoration of CAV1 may have clinical benefits in reducing APAP-induced vascular damage in NAFLD patients.

Exposure assessment of acetaminophen use in pregnancy: a study comparing self-reported intake with maternal and newborn biomarker measures

Background: Acetaminophen (APAP) is the most commonly used medication during pregnancy. Increasingly, studies have reported potential adverse associations between maternal prenatal use of APAP and offspring asthma, adverse reproductive outcomes, and neurodevelopmental disorders. However, most studies have relied on self-reported maternal exposure which has the potential for exposure misclassifications. We conducted this study to compare maternal self-reported APAP intake and three acetaminophen metabolites measured in urine collected during pregnancy and umbilical cord serum samples. Methods We used maternal interview data and biospecimens from the Nutrition in Pregnancy cohort of 2291 pregnant women recruited from Connecticut and Western Massachusetts during 1996-2000. We selected three exposure groups including 10 mothers who reported frequent intake (14 days+) of APAP in the first 3 months of pregnancy, 10 who reported frequent intake in the last 3 months of pregnancy, and 10 who reported never using APAP in these two periods from the cohort. We analyzed three APAP metabolites (parent compound, acetaminophen glucuronide, and 3-(N-acetyl-l-cystein-S-yl)-acetaminophen) levels in the maternal urine (avg. 24 gestational weeks) and the umbilical cord serum samples. Results The parent APAP compound and 3-(N-acetyl-l-cystein-S-yl)-acetaminophen) were detected in all urine and serum samples analyzed (100%), while acetaminophen glucuronide was less detectable in the cord serum (40% vs. 100% in urine). APAP metabolites in maternal urine and cord serum were correlated (r=0.43-0.70) within mother-child pairs. All three urinary and cord serum APAP metabolite levels were more strongly correlated with the reported number of days of APAP intake in late pregnancy (r=0.57-0.73; p-values &amp;#x3c;0.03, rank tests), and less with early pregnancy intake (r=0.18-0.34; p-values 0.21-0.60, rank tests). Conclusions Our findings suggest detailed intake data collected in maternal interviews is an efficient and valid measure to indicate exposure to APAP in pregnancy, while biomarker measures can be used to represent a specific exposure period of interest.

St. John's Wort Exacerbates Acetaminophen-Induced Liver Injury by Activation of PXR and CYP-Mediated Bioactivation.

St. John's wort (SJW) is a medicinal herb remedy for mild depression. However, long-term use of SJW has raised safety concerns in clinical practice because of drug-drug interactions. Excessive use of acetaminophen (APAP) causes severe hepatotoxicity, but whether SJW modulates APAP-induced liver injury remains unclear. In this study, the effect of long-term SJW administration on APAP-induced acute hepatotoxicity and the involved mechanisms were investigated. Morphological and biochemical assessments clearly demonstrated that SJW exacerbates APAP-induced toxicity. Moreover, SJW markedly promoted glutathione depletion and increased the levels of the APAP-cysteine and APAP-N-acetylcysteinyl adducts in mice, which enhanced APAP metabolic activation and aggravated APAP-induced liver injury. To further elucidate APAP metabolic activation in liver injury induced by SJW, the activities and expression levels of CYP2E1 and CYP3A were measured. The results showed that the activities and expression levels of CYP2E1 and CYP3A were increased after SJW treatment. Furthermore, the PXR-CYP signaling pathway was activated by SJW, and its downstream target genes were upregulated. Collectively, this study demonstrated that the long-term administration of SJW extract led to the metabolic activation of APAP and significantly exacerbated APAP-induced liver injury, which may suggest caution for the clinical use of SJW and APAP.

Probiotics: Evolving as a Potential Therapeutic Option against Acetaminophen-Induced Hepatotoxicity.

Acetaminophen (APAP) is the most common prescription medicine around the world for the treatment of pain and fever and is considered to be a safe drug at its therapeutic dose. However, a single overdose or frequent use of APAP can cause severe acute liver injury. APAP hepatotoxicity is a prevalent cause of acute liver disease around the world and the lack of suitable treatment makes it a serious problem. In recent years, there has been a surge in interest in using probiotics and probiotic-derived products, known as postbiotics, as health and disease negotiators. A growing body of evidence revealed that they can be equally effective against APAP hepatotoxicity. Different probiotic bacteria were found to be pre-clinically effective against APAP hepatotoxicity. Different postbiotics have also shown exciting results in preclinical models of APAP hepatotoxicity. This review summarized the protective roles and mechanisms of the different probiotic bacteria and postbiotics against APAP hepatotoxicity, with critical discussion. A brief discussion on potential novel probiotics and postbiotics for oxidative liver injury was also included. This review was written in an attempt to pique the interest of researchers in developing a safe therapeutic option against oxidative liver damage using probiotics and/or postbiotics as dietary supplements.

Protective effect of probiotics against acetaminophen induced nephrotoxicity.

Acetaminophen (APAP) is commonly prescribed as an antipyretic and analgesic agent in the practical field. Like every other drug(s), APAP also undergo metabolism by oxidation or conjugation by glucuronate and sulphate to form the toxic metabolite N-acetyl-p-benzoquinone imine (NAPQI). Moreover, the NAPQI is detoxified by conjugation with reduced glutathione (GSH). Interestingly, APAP is also metabolized in the kidney by deacetylation reaction in the presence of N-deacetylase enzyme into another severely toxic but minor metabolite, p-aminophenol. Both NAPQI and p-aminophenol shows nephrotoxicity as well as hepatotoxicity. Hence, the long-term therapeutic dose use and unnecessary overdose of APAP are of great concern as prolonged negligence may cost the nephrotoxicity that may lead to uremia and finally to kidney failure. It has recently been investigated that probiotic supplementation inhibits the sequential events associated with APAP-induced nephrotoxicity. This review emphasizes the role of different probiotics that have already been investigated in nephrotoxicity or uremia caused by APAP overdose.

EBNEO Commentary: Paracetamol/acetaminophen to avoid PDA ligation: How to interpret impact on 18- to 24-month outcomes.

Mashally S, Banihani R, Jasani B, Nield LE, Martins FF, Jain A, Weisz DE. Is late treatment with acetaminophen safe and effective in avoiding surgical ligation among extremely preterm neonates with persistent patent ductus arteriosus? J Perinatol 2021; Aug 21; 1–7. Online ahead of print. PMID 34453113. Acetaminophen (APAP) use among ELBW infants is increasing worldwide.1, 2 There is an urgent need to evaluate both the safety and efficacy of APAP for PDA treatment. In this retrospective study, Mashally and colleagues have compared outcomes of ELGANS in which differing approaches across two epochs were used for the treatment of a persistent PDA (pPDA) at a single centre: surgical ligation and APAP with ligation after failed closure. Comparing the neurodevelopmental outcomes of these infants at 18–24 months corrected age, the authors found no difference in the risk of NDI or death between infants treated for a pPDA between the two epochs. They conclude that APAP is a safe and effective therapy for late treatment of the PDA to avoid surgical ligation. These results add to the growing body of literature evaluating the use of APAP for PDA treatment. However, a number of issues must be considered. Although the authors state that the objective was to evaluate the ‘association of late treatment with acetaminophen vs. immediate surgical ligation with death or neurodevelopmental impairment (NDI) among extremely low gestational age neonates (ELGANs) with persistent patent ductus arteriosus (pPDA)’, this precise goal could not be met with the retrospective design and included subjects. Specifically, in epoch1 – the PDA ligation epoch – over 25% of the subjects did not undergo PDA ligation. In epoch2 – the APAP epoch – 20% were not exposed to APAP. Therefore, it is more accurate to state that this study compared outcomes across epochs with different prevailing clinical approaches to treatment of a late PDA. Furthermore, the small sample size also limits the ability to detect clinically relevant differences in outcomes. Larger observational and interventional studies that balance patient characteristics, avoid treatment contamination and minimise treatment selection bias are needed to determine the safety of APAP for pPDA. Lastly, any conclusion regarding the ‘safety’ of APAP must be considered in relation to the comparison therapy. In this study, the comparison was surgical ligation, which is an independent risk factor for poor neurodevelopmental outcomes.3 Given the risks of ligation, it could be argued that a pharmacologic approach that limits these exposures, and yet is not clearly safer, may potentially carry underappreciated risks that must be considered. The authors previously reported that late APAP exposure was associated with an increase in chronic lung disease.4 Although referenced in their methods, they do not comment further on this association here. The present report indicates that rates of moderate-severe bronchopulmonary dysplasia were 65% in epoch1 and 81% in epoch2 (p = 0.11). Although this difference did not reach statistical significance, a 16% absolute increase in the rates of this outcome is of possible clinical significance, particularly in the light of the reduced frequency of PDA ligation. This potential signal for harm, as well as the potential impact of APAP exposures on the developing lung, brain and endocrine function, reminds us that studies evaluating APAP safety should include broad measures of end-organ injury.5-7 With these points in mind, the conclusion regarding the safety of APAP should be regarded cautiously. URL LINK: URL TO THE FULL REVIEW ON THE EBNEO WEBSITE https://ebneo.org/apap-pda-ligation-18-24-month-outcomes None stated.

FXR-Deoxycholic Acid-TNF-α Axis Modulates Acetaminophen-Induced Hepatotoxicity.

The idiosyncratic characteristics and severity of acetaminophen (APAP) overdose-induced hepatotoxicity render identifying the predisposing factors and mechanisms of APAP-induced liver toxicity necessary and urgent. Farnesoid X receptor (FXR) controls bile acid homeostasis and modulates the progression of various liver diseases. Although global FXR deficiency in mice enhances APAP intoxication, the mechanism remains elusive. In this study, an increased sensitivity to APAP-induced toxicity was found in global Fxr-null (Fxr-/-) mice, but was not observed in hepatocyte-specific or macrophage-specific Fxr-null mice, suggesting that global FXR deficiency enhances APAP hepatotoxicity via disruption of systematic bile acid homeostasis. Indeed, more bile acid accumulation was found in global Fxr-/- mice, while 2% cholestyramine diet feeding decreased serum bile acids and alleviated APAP hepatotoxicity in global Fxr-/- mice, suggesting that bile acid accumulation contributes to APAP toxicity. Bile acids were suspected to induce macrophage to release tumor necrosis factor-α (TNF-α), which is known to enhance the APAP hepatotoxicity. In vitro, deoxycholic acid (DCA), a secondary bile acid metabolite, significantly induced Tnfa mRNA and dose-dependently enhanced TNF-α release from macrophage, while the same dose of DCA did not directly potentiate APAP toxicity in cultured primary hepatocytes. In vivo, DCA enhanced TNF-α release and potentiated APAP toxicity, both of which were abolished by the specific TNF-α antagonist infliximab. These results reveal an FXR-DCA-TNF-α axis that potentiates APAP hepatotoxicity, which could guide the clinical safe use of APAP.

Taste Masking of Granulated Acetaminophen by Water Insoluble Ethylcellulose Coating.

Bitter tasting of drugs leads to non-compliance especially in the case of pediatric patients due to their inability to swal-low medication. In this study, we aimed to mask the bitter taste of acetaminophen (APAP) particles through coating. A pH independent water insoluble ethylcellulose polymer was used to coat the APAP. The coating of water insoluble ethylcellulose on APAP can have a significant impact on the dissolution profile. Various grades of APAP were used for coating; fine grade, Compap L90% having wide particle size distribution (PSD), and a special granular (SG) APAP 1680 having narrow PSD. Coating was performed using top spray (Vector) for Compap L90% and SG APAP 1680 grade of APAP. Bitter taste of SG APAP was masked after spraying dispersion equivalent to a weight gain of 10% compared to 35% used for Compap L90%. Using bottom spray (Wurster coater, GPCP 2.0), coating was performed on SG APAP 1680 grade of APAP by spraying aqueous dispersion of ethylcellulose (Surelease) equivalent to a weight gain of 10%. The scalability of the top spray process was also evaluated in GPCG 30 and bitter taste was masked by using Surelease dispersion equivalent to a weight gain of 6%. Coated APAP was examined for particle size (PS), particle size distribution (PSD), flowability, and drug release profile. Dissolution was performed using USP apparatus 2 and 4 in phosphate buffer and evaluated for mechanism of drug release. Particle size obtained for coated SG APAP 1680 via top and bottom spray process was 404 µm d(90) and 487 µm d(90) respectively. The results of the study demonstrated the potential of Surelease dispersion in taste masking. The use of SG APAP 1680 having narrow PSD allowed taste masking to achieve at low weight gain without greatly affecting the dissolution profile.

Acetaminophen and the Developing Lung: Could There Be Lifelong Consequences?

Acetaminophen and the Developing Lung: Could There Be Lifelong Consequences?

Acetaminophen metabolism revisited using non-targeted analyses: Implications for human biomonitoring

The analgesic paracetamol/acetaminophen (N-acetyl-4-aminophenol, APAP) is commonly used to relieve pain, fever and malaise. While sales have increased worldwide, a growing body of experimental and epidemiological evidence has suggested APAP as a possible risk factor for various health disorders in humans. To perform internal exposure-based risk assessment, the use of accurate and optimized biomonitoring methods is critical. However, retrospectively assessing pharmaceutical use of APAP in humans is challenging because of its short half-life. The objective of this study was to address the key issue of potential underestimation of APAP use using current standard analytical methods based on urinary analyses of free APAP and its phase II conjugates. The question we address is whether investigating additional metabolites than direct phase II conjugates could improve the monitoring of APAP. Using non-targeted analyses based on high-resolution mass spectrometry, we identified, in a controlled longitudinal exposure study with male volunteers, overlooked APAP metabolites with delayed formation and excretion rates. We postulate that these metabolites are formed via the thiomethyl shunt after the enterohepatic circulation as already observed in rodents. Importantly, these conjugated thiomethyl metabolites were (i) of comparable diagnostic sensitivity as the free APAP and its phase II conjugates detected by current methods; (ii) had delayed peak levels in blood and urine compared to other APAP metabolites and therefore potentially extend the window of exposure assessment; and (iii) provide relevant information regarding metabolic pathways of interest from a toxicological point of view. Including these metabolites in future APAP biomonitoring methods therefore provides an option to decrease potential underestimation of APAP use. Moreover, our data challenge the notion that the standard methods in biomonitoring based exclusively on the parent compound and its phase II metabolites are adequate for human biomonitoring of a non-persistent chemical such as APAP.

Biochemical study on the protective effect of curcumin on acetaminophen and gamma-irradiation induced hepatic toxicity in rats.

Acetaminophen (APAP) is one of the few recommended analgesic and antipyretic drugs in some critical cases such as viral disease COVID-19. However, the unrestricted use of APAP develops liver disorders. Hepatotoxicity and liver injury can also be induced by ionizing radiation (IR) during radiotherapy. The data of the current study represents that treatment of rats with either APAP-overdose, or gamma-irradiation (R) induces hepatotoxicity, results in significant increases of the hepatic-enzymes activities (ALT, AST, ALP, GGT, LDH, and MDH), as well as enhancement of triglycerides, total cholesterol levels, combined with declines in albumin and total protein contents. An enhancement of the lipid peroxides (malondialdehyde; MDA), and nitric oxide levels along with a decline of reduced glutathione contents and suppression of superoxide dismutase, catalase, and glutathione peroxidase activities are also observed within the liver tissues of intoxicated animals. TNF-α, IL-1β, IL-6, iNOS, Cytochrome P450 2E1 (CYP2E1), miR-802 gene expression, NF-κB, and calcium levels are up-regulated, while Nuclear factor erythroid-related factor-2 (Nrf2), Hemoxygenase-1 (HO-1) protein and gene expressions, as well as, glutamate-cysteine ligase catalytic subunit (GCLC), NAD(P)H-Quinone oxidoreductase (NQO1), and miR-122 gene expressions are down-regulated in the livers of intoxicated animals. All these parameters show significant improvement in R/APAP intoxicated animals. Curcumin pretreatment develops an amelioration of these effects in APAP-overdose, R-exposure, or R/APAP treatments. In conclusion, oral administration of curcumin shows hepatoprotective effects against APAP-overdose induced hepatic damage in normal and gamma-irradiated rats through prospective regulation of the therapeutic targets CYP2E1, Nrf2, and NF-κB, via organizing the miR-122 and miR-802 gene expression.

Influence of acetaminophen on renal function: a longitudinal descriptive study using a real-world database.

Long-term acetaminophen (APAP) use has poorly defined effects on renal function. We investigated these effects using a real-world database. We used a database of health data routinely collected from 185 hospitals serving 20 million patients in Japan. Individuals with chronic pain were selected for the study. The primary outcome was the change in renal function, as measured by 1/serum creatinine (SCr) during the postindex period. After excluding individuals who did not meet the inclusion criteria, 241,167 patients were included in the analysis (median age 79.0, range 65-101years; 111,252 were men). APAP was prescribed significantly more frequently to patients with a low renal function (P < 0.001). The annual changes in 1/SCr median and interquartile range (IQR) were -0.038 (-0.182 to 0.101) in patients receiving APAP, -0.040 (-0.187 to 0.082) in patients receiving non-steroidal anti-inflammatory drugs (NSAIDs), and -0.025 (-0.142 to 0.079) in nonmedicated control patients (P < 0.001). These changes were not significantly different among patients with a low renal function, with 0.003 (-0.066 to 0.113) in the APAP group, 0.000 (-0.089 to 0.090) in the NSAID group, and -0.009 (-0.086 to 0.089) in the control group (P = 0.327). Physicians tended to select APAP for individuals with a low renal function. The annual changes in 1/SCr were significantly different based on APAP and NSAID use or no analgesia, but the differences were not significant among patients with a low renal function. Overall, long-term use of APAP does not appear to exacerbate the renal function in a clinical setting.

Is Concomitant Therapy with Acetaminophen and Low-dose Aspirin a Risk Factor for CKD Progression? A 6-Year Cohort Study

Concomitant therapy with acetaminophen (APAP) and low-dose aspirin is often used in clinical settings; however, it is unclear whether this combination is involved in the progression of chronic kidney disease (CKD). We hypothesized that concomitant therapy with APAP and low-dose aspirin may cause CKD progression. We carried out a retrospective 6-year cohort study that included all patients who received low-dose aspirin from January 2011 to December 2016 at Kaetsu Hospital. Primary outcome was defined as CKD progression at the end of the study compared with baseline. Among the 441 patients treated during the study period, we identified 89 cases of CKD progression. Multivariate regression analysis showed that exposure to APAP>50 g [odds ratio (OR), 2.68, 95% confidence interval (CI), 1.08-6.70], age increase by 1 year (OR, 1.05, 95% CI, 1.02-1.08), and diabetes mellitus (OR, 2.40, 95% CI, 1.41-4.08) had positive associations with CKD progression. Our findings suggested that concomitant therapy with APAP and low-dose aspirin increased the risk of CKD progression. Therefore, we recommend more thorough monitoring of serum creatinine when patients are on such concomitant therapy. Moreover, it is important to advise users of low-dose aspirin to avoid unnecessary use of APAP, in order to reduce the risk of CKD progression.

Hepatic Adaptation to Therapeutic Doses of Acetaminophen: An Exploratory Study in Healthy Individuals

PurposeAcetaminophen (APAP) has hepatotoxic potential when overdosed. Recent studies have reported serum alanine aminotransferase (ALT) elevations that resolve spontaneously with continued use of the drug, referred to as adaptation, in several individuals receiving therapeutic doses of APAP. However, the clinical significance of these ALT elevations remains unclear. This study was performed to investigate the incidence and characteristics of hepatic adaptation to therapeutic doses of APAP in healthy individuals. MethodsIn a randomized, single-blind, placebo-controlled study, 242 healthy Japanese individuals were enrolled. Each person received 3 g/d of APAP (n = 202) or placebo (n = 40) for 28 days. All study participants underwent analysis of genetic polymorphisms of CYP2E1 and UGT1A1; measurements of plasma APAP concentration and urine metabolites (glucuronide, sulfate, cysteine, and mercapturate); liver function monitoring, including ALT, microRNA-122, and high-mobility group box 1. Individuals with ALT levels remaining below the upper limit of normal (ULN; 40 U/L) during the study period were defined as tolerant and those with ALT elevations above the ULN as susceptible. Susceptible individuals who developed ALT elevations exceeding 2 × ULN discontinued use of the study drug for tolerability consideration. Susceptible individuals who had ALT elevations that decreased toward the ULN spontaneously with continued use of the study drug were classified as adaptation. FindingsIn the APAP group, 129 individuals (66%) were classified as tolerant and 65 (34%) as susceptible. Among 65 susceptible individuals, 12 (18%) discontinued use of APAP because of ALT elevations (>2 × ULN), whereas 53 (82%) completed 28-day APAP dosing. Thirty of 65 susceptible individuals (46%) had adaptation within 28 days. In the placebo group, no individuals was withdrawn from the study because of elevated ALT levels, 33 individuals (89%) were classified as tolerant, and 4 (11%) were classified as susceptible. None had clinical signs of liver injury. ALT level correlated significantly with microRNA-122 but not with high-mobility group box 1. No association was found between plasma APAP concentrations and ALT levels. Urinary excretion of APAP mercapturate was higher in susceptible than in tolerant individuals (P = 0.018, Wilcoxon or Kruskal-Wallis test). The frequency of homozygotes and compound heterozygotes for UGT1A1∗28 and UGT1A1∗6 (∗28/∗28, ∗6/∗6, and ∗6/∗28) was higher in susceptible than in tolerant individuals (13.9% vs 3.9%; P = 0.011, χ2 test). ImplicationsThese findings indicate that in healthy individuals, APAP at a therapeutic dose can cause transient and self-limiting ALT elevation, reflecting subclinical hepatocellular damage, and these ALT elevations may be associated with the disposition of APAP metabolites and genetic factors. UMIN-CTR identifier: UMIN000019607.

A novel pipeline of 2-(benzenesulfonamide)-N-(4-hydroxyphenyl) acetamide analgesics that lack hepatotoxicity and retain antipyresis

Although acetaminophen (ApAP) is one of the most commonly used medicines worldwide, hepatotoxicity is a risk with overdose or in patients with compromised liver function. ApAP overdose is the most common cause of acute fulminant hepatic failure. Oxidation of ApAP to N-acetyl-p-benzoquinone imine (NAPQI) is the mechanism for hepatotoxicity. 1 is a non-hepatotoxic, metabolically unstable lipophilic ApAP analog that is not antipyretic. The newly synthesized 3 is a non-hepatotoxic ApAP analog that is stable, lipophilic, and retains analgesia and antipyresis. Intraperitoneal or po administration of the new chemical entities (NCEs), 3b and 3r, in concentrations equal to a toxic dose of ApAP did not result in the formation of NAPQI. Unlike livers from NCE-treated mice, the livers from ApAP-treated mice demonstrated large amounts of nitrotyrosine, a marker of mitochondrial free radical formation, and loss of hepatic tight junction integrity. Given the widespread use of ApAP, hepatotoxicity risk with overuse, and the ongoing opioid epidemic, these NCEs represent a novel, non-narcotic therapeutic pipeline.