Antipyretic effects of dipyrone versus ibuprofen versus acetaminophen in children: results of a multinational, randomized, modified double-blind study

Common Selfcare Indications of Pain Medications in Children

Pain has a multifaceted impact on individuals worldwide, affecting their physical functioning, emotional well-being, and quality of life. Children (age < 18 years) have a high prevalence of conditions associated with pain, such as toothache, headache, earache, sore throat, and respiratory tract infections, many of which may be accompanied by fever. Globally, the pharmacologic treatment of pain in pediatric patients is limited largely to nonopioid analgesics, and dosing must account for differences in age, weight, metabolism, and risk of adverse effects. This narrative review summarizes the findings of a literature search on the pediatric indications, dosing approaches, dosing guidelines, and pharmacokinetics of paracetamol and ibuprofen, which are common pain medications available globally for self-care use in children. The review also discusses the risks and benefits associated with these agents. The current roles of paracetamol and ibuprofen in the symptomatic management of coronavirus disease 2019 (COVID-19) infection and in the management of post-COVID-19 immunization symptoms in children are also discussed. Therefore, while a very large amount of data over several decades is available for paracetamol and ibuprofen, an urgent need exists for well-designed studies of these medications for the management of pain and fever in pediatric patients with COVID-19 to ensure optimal relief with minimal toxicity.

Paracetamol (acetaminophen) use in infants and children was never shown to be safe for neurodevelopment: a systematic review with citation tracking

Although widely believed by pediatricians and parents to be safe for use in infants and children when used as directed, increasing evidence indicates that early life exposure to paracetamol (acetaminophen) may cause long-term neurodevelopmental problems. Furthermore, recent studies in animal models demonstrate that cognitive development is exquisitely sensitive to paracetamol exposure during early development. In this study, evidence for the claim that paracetamol is safe was evaluated using a systematic literature search. Publications on PubMed between 1974 and 2017 that contained the keywords "infant" and either "paracetamol" or "acetaminophen" were considered. Of those initial 3096 papers, 218 were identified that made claims that paracetamol was safe for use with infants or children. From these 218, a total of 103 papers were identified as sources of authority for the safety claim.   Conclusion: A total of 52 papers contained actual experiments designed to test safety, and had a median follow-up time of 48 h. None monitored neurodevelopment. Furthermore, no trial considered total exposure to drug since birth, eliminating the possibility that the effects of drug exposure on long-term neurodevelopment could be accurately assessed. On the other hand, abundant and sufficient evidence was found to conclude that paracetamol does not induce acute liver damage in babies or children when used as directed. What is Known: • Paracetamol (acetaminophen) is widely thought by pediatricians and parents to be safe when used as directed in the pediatric population, and is the most widely used drug in that population, with more than 90% of children exposed to the drug in some reports. • Paracetamol is known to cause liver damage in adults under conditions of oxidative stress or when used in excess, but increasing evidence from studies in humans and in laboratory animals indicates that the target organ for paracetamol toxicity during early development is the brain, not the liver. What is New: • This study finds hundreds of published reports in the medical literature asserting that paracetamol is safe when used as directed, providing a foundation for the widespread belief that the drug is safe. • This study shows that paracetamol was proven to be safe by approximately 50 short-term studies demonstrating the drug's safety for the pediatric liver, but the drug was never shown to be safe for neurodevelopment. Paracetamol is widely believed to be safe for infants and children when used as directed, despite mounting evidence in humans and in laboratory animals indicating that the drug is not safe for neurodevelopment. An exhaustive search of published work cited for safe use of paracetamol in the pediatric population revealed 52 experimental studies pointing toward safety, but the median follow-up time was only 48 h, and neurodevelopment was never assessed.

Comparative evaluation of the efficacy of intravenous paracetamol and ibuprofen on the treatment of tonsillopharyngitis with fever: A prospective, randomized controlled, double-blind clinical trial

OBJECTIVE:

Tonsillopharyngitis is one of the constituents of upper respiratory tract infection (URTI). Fever is a URTI symptom requiring treatment due to the occurrence of discomfort and high fever-based complications. This study primarily sets out to observe and compare the efficacy of intravenous administration of paracetamol and ibuprofen drugs on fever in adult patients with tonsillopharyngitis.

METHODS:

This study was performed in a prospective, randomized controlled, double-blind design. The study population was divided as Group 1 (treated with paracetamol) and as Group 2 (treated with ibuprofen). While the first group was treated with paracetamol as 1000 mg in 150 ml normal saline, the second group was treated with ibuprofen as 400 mg in 150 ml normal saline. The primary outcome was the decrease in fever at 15, 30, and 60 min, while the secondary outcome was the need for additional treatment after 60 min.

RESULTS:

One hundred and eighty-five patients were included in the final analysis. The mean age of the paracetamol group (57.4% male) was 28.36 ± 9.6, whereas that of the ibuprofen group (54.9% male) was 27.45 ± 7.98. Fever was reduced significantly between 0 and 60 min in both groups (P ≤ 0.001 and P ≤ 0.001, respectively). Although the antipyretic effect of ibuprofen was more pronounced in the early period than that of paracetamol, no significant difference was noted between the two groups in terms of fever drop between 0 and 60 min (P = 0.350).

CONCLUSION:

Although both drugs prove effective in controlling fever at the 60 min, stronger efficacy of ibuprofen in the first 15 min may enable rapid discharge from the emergency department.

Acetaminophen and ibuprofen in the treatment of pediatric fever: a narrative review

OBJECTIVE

A narrative review of randomized, blinded, controlled studies assessing the antipyretic effect of ibuprofen versus acetaminophen or combined or alternating treatment in children was conducted.

METHODS

Searches of the PubMed and Embase literature databases were conducted to identify relevant articles. Selected articles were limited to studies published in English that investigated OTC oral tablet and syrup formulations of acetaminophen and ibuprofen; there were no publication date limits. Open-label studies, nonrandomized studies, and those evaluating intravenous or suppository formulations of acetaminophen or ibuprofen were excluded. Variations in designs, endpoints, methods, and patient populations precluded our ability to conduct a formal systematic review.

RESULTS

At physician-directed dosing (acetaminophen 15 mg/kg vs ibuprofen 10 mg/kg), no significant differences in antipyretic effects from 0‒6 h and between 0‒6, ‒12, ‒24, or ‒48 h, with single or multiple-doses, respectively, were observed. Tolerability profiles at physician dosing were similar. In 14 over-the-counter dose comparisons (acetaminophen, 10-15 mg/kg; ibuprofen, 2.5-10 mg/kg), antipyresis favored ibuprofen in 6, was similar between groups in 7, and favored acetaminophen (15 mg/kg vs ibuprofen 5 mg/kg) in 1 comparison. Both medications were well tolerated. Efficacy favored combination over individual components in 3 of 4 studies; alternating use results were mixed. All combination or alternating treatments were well tolerated.

CONCLUSIONS

Antipyretic effects of ibuprofen and acetaminophen are similar at physician-directed doses; ibuprofen may be modestly superior at over-the-counter doses.

Symptomatic fever management in children: A systematic review of national and international guidelines

INTRODUCTION

Divergent attitudes towards fever have led to a high level of inconsistency in approaches to its management. In an attempt to overcome this, clinical practice guidelines (CPGs) for the symptomatic management of fever in children have been produced by several healthcare organizations. To date, a comprehensive assessment of the evidence level of the recommendations made in these CPGs has not been carried out.

METHODS

Searches were conducted on Pubmed, google scholar, pediatric society websites and guideline databases to locate CPGs from each country (with date coverage from January 1995 to September 2020). Rather than assessing overall guideline quality, the level of evidence for each recommendation was evaluated according to criteria of the Oxford Centre for Evidence-Based Medicine (OCEBM). A GRADE assessment was undertaken to assess the body of evidence related to a single question: the threshold for initiating antipyresis. Methods and results are reported according to the PRISMA statement.

RESULTS

74 guidelines were retrieved. Recommendations for antipyretic threshold, type and dose; ambient temperature; dress/covering; activity; fluids; nutrition; proctoclysis; external applications; complementary/herbal recommendations; media; and age-related treatment differences all varied widely. OCEBM evidence levels for most recommendations were low (Level 3-4) or indeterminable. The GRADE assessment revealed a very low level of evidence for a threshold for antipyresis.

CONCLUSION

There is no recommendation on which all guidelines agree, and many are inconsistent with the evidence-this is true even for recent guidelines. The threshold question is of fundamental importance and has not yet been answered. Guidelines for the most frequent intervention (antipyresis) remain problematic.

An Experimental and Theoretical Approach to Understand Fever, DENF & its Cure

Fever is a response of a human body, due to an increase in the temperature, against certain stimuli. It may be associated with several reasons and one of the major causes of fever is a mosquito bite. Fever due to dengue virus (DENV) infection is being paid most attention out of several other fever types because of a large number of deaths reported worldwide. Dengue virus is transmitted by biting of the mosquitoes, Aedes aegypti and Aedes albopictus. DENV1, DENV2, DENV3 and DENV4 are the four serotypes of dengue virus and these serotypes have 65% similarities in their genomic structure. The genome of DENV is composed of single-stranded RNA and it encodes for the polyprotein. Structural and non-structural proteins (nsP) are the two major parts of polyprotein. Researchers have paid high attention to the non-structural protease (nsP) of DENV like nsP1, nsP2A, nsP2B, nsP3, nsP4A, nsP4B and nsP5. The NS2B-NS3 protease of DENV is the prime target of the researchers as it is responsible for the catalytic activity. In the present time, Dengvaxia (vaccine) is being recommended to patients suffering severely from DENV infection in few countries only. Till date, neither a vaccine nor an effective medicine is available to combat all four serotypes. This review describes the fever, its causes, and studies to cure the infection due to DENV using theoretical and experimental approaches.

Risk of wheezing and asthma exacerbation in children treated with paracetamol versus ibuprofen: a systematic review and meta-analysis of randomised controlled trials

Background

Paracetamol and ibuprofen are the most commonly used medications for fever and pain management in children. While the efficacy appears similar with both drugs, there are contradictory findings related to adverse events. In particular, incidence of wheezing and asthma among children taking paracetamol compared to ibuprofen, remain unsettled.

Methods

We conducted a meta-analysis of randomized controlled trials (RCTs) that compared wheezing and asthma exacerbations in children taking paracetamol versus ibuprofen. A comprehensive search was conducted in five databases. RCTs reporting on cases of wheezing or asthma exacerbations in infants or children after the administration of paracetamol or ibuprofen were included. The pooled effect size was estimated using the Peto’s odds ratio.

Results

Five RCTs with 85,095 children were included in the analysis. The pooled estimate (OR 1.05; 95%CI 0.76–1.46) revealed no difference in the odds of developing asthma or presenting an exacerbation of asthma in children who received paracetamol compared to ibuprofen. When the analysis was restricted to RCTs that examined the incidence of asthma exacerbation or wheezing, the pooled estimate remained similar (OR 1.01; 95%CI 0.63–1.64). Additional bias adjusted quality effect sensitivity model yielded similar results (RR 1.03; 95%CI 0.84–1.28).

Conclusion

Although, Ibuprofen and paracetamol appear to have similar tolerance and safety profiles in terms of incidence of asthma exacerbations in children, we suggest high quality trials with clear definition of asthma outcomes after receiving ibuprofen or paracetamol at varying doses with longer follow-up are warranted for any conclusive finding.

The Effect of Acetaminophen on Temperature in Critically Ill Children: A Retrospective Analysis of Over 50,000 Doses

OBJECTIVES

Acetaminophen is widely used in PICUs. Although randomized controlled trials suggest that acetaminophen significantly reduces body temperature in adults, the effect of acetaminophen on temperature in critically ill children has not been previously quantified.

DESIGN

Retrospective observational cohort study.

SETTING

Single-center general and cardiac PICU in a specialist children's hospital.

PATIENTS

All children who received acetaminophen or had a fever (temperature ≥ 38°C) while on the ICU over a 40-month period (September 2012 to December 2015).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

In total, 58,177 doses of acetaminophen were administered, with temperature data available for analysis for 54,084 doses. Temperature decreased by 0.11°C (95% CI, 0.09-0.14°C) 4 hours post acetaminophen dose, after adjustment for weight and illness severity. In children who had a fever and were given acetaminophen, temperature decreased by 0.78°C (95% CI, 0.74-0.82°C). Temperature decreased by 0.88°C (95% CI, 0.85-0.92°C) in children who had fever but did not receive acetaminophen. The change in temperature associated with fever was significantly different between those who did and did not receive acetaminophen (likelihood ratio statistic 246.06; p < 2.2 × 10(-16)).

CONCLUSIONS

Acetaminophen is associated with a significant decrease in temperature in children with fever. However, temperature may decrease following fever without acetaminophen in the PICU. The threshold to use acetaminophen must be understood to determine the true effect on temperature in any future trials.

Randomized, controlled, multicentre clinical trial of the antipyretic effect of intravenous paracetamol in patients admitted to hospital with infection

Aim

No randomized study has been conducted to investigate the use of intravenous paracetamol (acetaminophen, APAP) for the management of fever due to infection. The present study evaluated a new ready‐made infusion of paracetamol.

Methods

Eighty patients with a body temperature onset ≥38.5°C in the previous 24 h due to infection were randomized to a single administration of placebo (n = 39) or 1 g paracetamol (n = 41), and their temperature was recorded at standard intervals. Rescue medication with 1 g paracetamol was allowed. Serum samples were collected for the measurement of APAP and its metabolites. The primary endpoint was defervescence, defined as a core temperature ≤37.1°C.

Results

During the first 6 h, defervescence was achieved in 15 (38.5%) patients treated with placebo compared with 33 (80.5%) patients treated with paracetamol 1 g (P < 0.0001). The median time to defervescence with paracetamol 1 g was 3 h. Rescue medication was given to 15 (38.5%) and five (12.2%) patients allocated to placebo and paracetamol, respectively (P = 0.007); nine (60.0%) and two (40.0%) of these patients, respectively, experienced defervescence. No further antipyretic medication was needed for patients becoming afebrile with rescue medication. Serum glucuronide‐APAP concentrations were significantly greater in the serum of patients who did not experience defervescence with paracetamol. The efficacy of paracetamol was not affected by serum creatinine. No drug‐related adverse events were reported.

Conclusions

The 1 g paracetamol formulation has a rapid and sustainable antipyretic effect on fever due to infection. Its efficacy is dependent on hepatic metabolism.

[Septic shock secondary to non-congenital chikungunya fever in a young infant: A clinical case]

INTRODUCTION

A chikungunya outbreak took place in the State of Yucatan starting in the second half of 2015 OBJECTIVE: To analyse the clinical course of a case of chikungunya in a previously healthy infant, providing practical evidence to guide future diagnoses and treatment during outbreak seasons in endemic areas

CASE REPORT

Clinical manifestation started with a sudden onset of fever and a diffuse macular-papillary erythema, originally treated in the community with non-steroidal anti-inflammatory drugs. Two days later, the fever relapsed with hypoactivity, severe thrombocytopenia and neutropenia (without lymphopenia), respiratory distress, liver dysfunction, sepsis, followed by septic shock with a fatal outcome. IgM test was positive to chikungunya, while her mother tested negative. Pseudomonas aeruginosa was isolated from the blood culture possible due to contamination, without ruling out the possibility of a mixed origin sepsis.

CONCLUSIONS

Chikungunya is a disease in which the manifestations in neonates and young infants can be severe, and even fatal. It is important to suspect it in this age group at risk of vector contact, in the presence of fever without apparent source of infection and cutaneous manifestations. It is important to use the antipyretics cautiously, considering the possibility of aggravating the underlying infection, and the potential hepatic and haematological damage.

Recent Advances in Pediatric Use of Oral Paracetamol in Fever and Pain Management

Paracetamol is a common analgesic and antipyretic drug for management of fever and mild-to-moderate pain in infants and children, and it is considered as first-line therapy for the treatment of both according to international guidelines and recommendations. The mechanism of action of paracetamol is complex and multifactorial, and several aspects of the pharmacology impact its clinical use, especially in the selection of the correct analgesic and antipyretic dose. A systematic literature search was performed by following procedures for transparent reporting of systematic reviews and meta-analyses. To maximize efficacy and avoid delays in effect, use of the appropriate dose of paracetamol is paramount. Older clinical studies using paracetamol at subtherapeutic doses of ≤10 mg/kg generally show that it is less effective than non-steroidal anti-inflammatory drugs (NSAIDs). However, recent evidence shows that when used at dose of 15 mg/kg for fever and pain management, paracetamol is significantly more effective than placebo, and at least as effective as NSAIDs. Paracetamol 15 mg/kg has a tolerability profile similar to that of placebo and NSAIDs such as ibuprofen and ketoprofen used for short-term treatment of fever. However, when used at repetitive doses for consecutive days, paracetamol shows lower risk of adverse events compared to NSAIDs. Also, unlike NSAIDs, paracetamol is indicated for use in children of all ages. Overall, clinical evidence qualifies paracetamol 15 mg/kg a safe and effective option for treatment of pain and fever in children.

Streocontrolled construction of six vicinal stereogenic centers on spiropyrazolones via organocascade Michael/Michael/1,2-addition reactions

A highly stereoselective one-pot procedure for the synthesis of spiropyrazolone derivatives bearing six contiguous stereogenic centers including two tetrasubstituted carbons has been developed. Under sequential catalysis by two organocatalysts, a cinchona-derived aminosquaramide and DBU, a series of diversely functionalized spiropyrazolones are obtained in good yields (47-62%) and excellent stereoselectivities (up to >25:1 dr and 98-99% ee). The opposite enantiomers of the spiropyrazolones are also accessible by employing a pseudoenantiomeric aminosquaramide catalyst.

Crystal structure, DFT, spectroscopic and biological activity evaluation of analgin complexes with Co(ii), Ni(ii) and Cu(ii)

Coordination of analgin to Ni(ii) and Cu(ii) ions as a mono-negatively tridentate ligand leads to a significant increase in its antibacterial activity compared with the Co(ii) complex.

The efficacy of intravenous paracetamol versus dipyrone for postoperative analgesia after day-case lower abdominal surgery in children with spinal anesthesia: a prospective randomized double-blind placebo-controlled study

BACKGROUND

A multimodal and preventative approach to providing postoperative analgesia is becoming increasingly popular for children and adults, with the aim of reducing reliance on opioids. We conducted a prospective, randomized double-blind study to compare the analgesic efficacy of intravenous paracetamol and dipyrone in the early postoperative period in school-age children undergoing lower abdominal surgery with spinal anesthesia.

METHODS

Sixty children scheduled for elective lower abdominal surgery under spinal anesthesia were randomized to receive either intravenous paracetamol 15 mg/kg, dipyrone 15 mg/kg or isotonic saline. The primary outcome measure was pain at rest, assessed by means of a visual analog scale 15 min, 30 min, 1 h, 2 h, 4 h and 6 h after surgery. If needed, pethidine 0.25 mg/kg was used as the rescue analgesic. Time to first administration of rescue analgesic, cumulative pethidine requirements, adverse effects and complications were also recorded.

RESULTS

There were no significant differences in age, sex, weight, height or duration of surgery between the groups. Pain scores were significantly lower in the paracetamol group at 1 h (P = 0.030) and dipyrone group at 2 h (P = 0.010) when compared with placebo. The proportion of patients requiring rescue analgesia was significantly lower in the paracetamol and dipyrone groups than the placebo group (vs. paracetamol P = 0.037; vs. dipyrone P = 0.020). Time to first analgesic requirement appeared shorter in the placebo group but this difference was not statistically significant, nor were there significant differences in pethidine requirements, adverse effects or complications.

CONCLUSION

After lower abdominal surgery conducted under spinal anesthesia in children, intravenous paracetamol appears to have similar analgesic properties to intravenous dipyrone, suggesting that it can be used as an alternative in the early postoperative period.

TRIAL REGISTRATION

Clinical Trials.gov. Identifier: NCT01858402.

Dosing and antipyretic efficacy of oral acetaminophen in children

BACKGROUND

A standardized approach to dosing acetaminophen in pediatric populations was published in 1983. That review proposed specific weight-related dosing for infants and children weighing 6 through 95 lb and an age-based schedule for children aged <4 months through 11 years. Subsequent clinical studies evaluating these and alternative doses of acetaminophen supported the recommended 10-15-mg/kg dose.

OBJECTIVE

This article reviewed published and unpublished pediatric antipyretic data to provide a critical assessment of the 10-15-mg/kg oral dose and the current pediatric oral dosing schedules for acetaminophen.

METHODS

Published literature and unpublished clinical trials that evaluated the antipyretic efficacy of acetaminophen in children were reviewed. The PubMed database was searched using the term acetaminophen or paracetamol, with study criteria limited to randomized, controlled trials; oral dosing; patient age <12 years; and publication between 1982 and August 2012. All of the sponsor's unpublished antipyretic clinical studies completed between 1980 and August 2012 and involving at least 1 oral-formulation acetaminophen-only treatment arm were identified. Data from published literature containing sufficient detail to verify doses; dosing frequency; and, when necessary, estimates from figures, and from acetaminophen arms of the unpublished studies were analyzed.

RESULTS

Thirteen unpublished trials enrolled 705 children to receive an oral dose of 10-15 mg/kg of acetaminophen. This dose resulted in a rapid onset of temperature reduction, with a maximum temperature decrement of ~3 hours following administration. Results from 40 published clinical trials in which 2332 children received oral acetaminophen for fever support these findings. The most common adverse events reported in any of the reported studies were gastrointestinal in nature and generally mild in intensity.

CONCLUSIONS

Data support the recommended 10-15-mg/kg oral dose and demonstrate that the age and weight schedules for over-the-counter acetaminophen proposed in 1983 remain appropriate.

Efficacy and Safety of Ibuprofen and Acetaminophen in Children and Adults: A Meta-Analysis and Qualitative Review

Objective:

To evaluate the analgesic and antipyretic efficacy and safety of ibuprofen compared to acetaminophen in children and adults.

Data Sources:

Literature searches were performed using PubMed/MEDLINE (through August 2009) and EMBASE (through January 2008) and were restricted to the English language. In PubMed/MEDLINE, search terms used were ibuprofen, acetaminophen, paracetamol, clinical trials, and randomized controlled trials. EMBASE search terms included ibuprofen and acetaminophen, restricted to human and clinical trials.

Study Selection And Data Extraction:

All English-language articles identified from the data sources were reviewed. Multiple review articles were studied for any pertinent references and this yielded additional articles. Only articles that directly compared ibuprofen and acetaminophen were eligible for this review.

Data Synthesis:

Eighty-five studies that directly compared ibuprofen to acetaminophen were identified; 54 contained analgesic efficacy data, 35 contained antipyretic/temperature reduction data, and 66 contained safety data (some articles contained more than 1 type of data). Qualitative review of the literature revealed that, for the most part, ibuprofen was more efficacious than acetaminophen for the treatment of pain and fever in both pediatric and adult populations, and that these 2 drugs were equally safe. Meta-analyses on the subset of randomized clinical trial articles that reported sufficient quantitative information to calculate either an odds ratio (adverse event [AE]) or standardized mean difference (pain and fever) confirmed the qualitative results for adult (standardized mean difference [SMD] 0.69; 95% CI 0.57 to 0.81) and pediatric (SMD 0.28; 95% CI 0.10 to 0.46) pain at 2 hours postdose and pediatric fever (SMD 0.26; 95% CI 0.10 to 0.41) at 4 hours postdose. Conclusions regarding adult fever/temperature reduction could not be made due to a lack of evaluable data. The combined odds ratio for the proportion of adult subjects experiencing at least 1 AE slightly favored ibuprofen; however, the difference was not statistically significant (1.12; 95% CI 1.00 to 1.25). No significant difference between drugs in AE incidence was found for pediatric patients (0.82; 95% CI 0.60 to 1.12).

Conclusions:

Ibuprofen is as or more efficacious than acetaminophen for the treatment of pain and fever in adult and pediatric populations and is equally safe.

Systematic review and meta-analysis of the clinical safety and tolerability of ibuprofen compared with paracetamol in paediatric pain and fever

OBJECTIVE

The main aim of this review was to compare the tolerability and safety between ibuprofen and paracetamol when used as anti-pyretic and analgesic agents in children up to 18 years of age.

METHODS

MEDLINE (1950 to November 2008), EMBASE (1980 to November 2008), The Cochrane Library (2007, Issue 3), ACP Journal Club (1991 to November 2007) and Pascal (1987 to November 2007) were searched for randomised controlled trails (RCTs) (comparing ibuprofen and/or paracetamol with placebo), controlled observational studies and large case series comprised more than 1000 participants.

MAIN OUTCOME MEASURES

Adverse events (AEs) requiring discontinuation of medication; systemic reactions related to ibuprofen or paracetamol; serious AEs that are fatal, life-threatening or require hospitalisation; and serious AEs not requiring hospitalisation.

RESULTS

A total of 24 RCTs examined either ibuprofen and/or paracetamol versus placebo for AE data. Twelve other studies meeting our criteria were also included for AE data. Meta-analysis of systemic reactions demonstrated that tolerability and safety of ibuprofen was similar to placebo, as was paracetamol: ibuprofen versus placebo relative risk (RR) 1.39 (95% CI: 0.92, 2.10); paracetamol versus placebo RR 1.57 (95% CI 0.74, 3.33). A total of 2937 systemic AEs occurred in 21,305 patients taking ibuprofen compared with 1,466 systemic AEs in 11,164 patients taking paracetamol: RR 1.03 (95% CI 0.98, 1.10). There was no significant difference between the two groups. Narrative analysis of AE data identified conflicting evidence regarding hepatic injury with paracetamol and group A streptococcal infections with ibuprofen or paracetamol treatment.

CONCLUSIONS

Ibuprofen, paracetamol and placebo have similar tolerability and safety profiles in terms of gastrointestinal symptoms, asthma and renal adverse effects. While the study data investigated here may not reflect over-the-counter use, these results are still relevant in the context of any safety concerns relating to general ibuprofen or paracetamol treatment in children.

Intramuscular Dipyrone versus Oral Ibuprofen or Nimesulide for Reduction of Fever in the Outpatient Setting

OBJECTIVE

To compare the effectiveness and rate of temperature reduction of three antipyretic medications in febrile children.

DESIGN

A single-dose, randomised, prospective, modified double-blind, parallel clinical trial.

SETTING

The paediatric emergency department of a university hospital that has 13 000 annual visits.

STUDY PARTICIPANTS

252 otherwise healthy children aged 6 months to 14 years with acute, intercurrent, febrile illness.

INTERVENTIONS

Enrolled children were assigned to receive a single dose of oral ibuprofen 10 mg/kg, oral nimesulide 2.5 mg/kg, or parenteral dipyrone 10 mg/kg.

MAIN OUTCOME MEASURES AND RESULTS

Axillary temperature was measured at the time of antipyretic administration and at 30, 45, 60 and 120 minutes thereafter. All three medications were effective in reducing the axillary temperature during the 2-hour testing period. The rates of axillary temperature change between the three medications were significantly different for the ibuprofen and dipyrone groups (p = 0.023). In addition, the axillary temperature in the dipyrone group was significantly lower than that in the ibuprofen group (p = 0.036) at 120 minutes. There was no significant difference in antipyretic effect between the nimesulide group and the other two groups during the testing period. Within each group the difference between initial temperature and the temperature at the end of the testing period was statistically significant (p = 0.036) for the dipyrone group only.

CONCLUSIONS

All three antipyretic medications were effective in reducing the axillary temperature in febrile children. Although administration of intramuscular dipyrone seemed to be more effective than ibuprofen, this relationship was not significant when nimesulide was considered. In addition, in view of its known side effects and the problems associated with intramuscular administration in children, the preference for orally administered nimesulide or ibuprofen over dipyrone in the setting of the emergency department seems more logical provided that the child accepts oral therapy.

Antipyretic efficacy and tolerability of oral ibuprofen, oral dipyrone and intramuscular dipyrone in children: a randomized controlled trial

CONTEXT AND OBJECTIVE

Dipyrone is a widely used over-the-counter antipyretic in Latin America, and elsewhere among Latin immigrants. Despite limited evidence, physicians often prescribe oral ibuprofen or intramuscular dipyrone as the most effective antipyretics. Our aim was to compare the antipyretic efficacy and tolerability of a single dose of oral ibuprofen, oral dipyrone or intramuscular dipyrone in febrile children.

DESIGN AND SETTING

Randomized, single-blind clinical trial, at San Bartolomé Mother-Child National Teaching Hospital, Lima, Peru.

METHODS

Children from six months to six years old with fever (rectal temperature: 38.3 to 39.8 degrees C) in the emergency ward between February and June 2003 were eligible. Seventy-five children were randomly assigned to receive a single dose of oral ibuprofen (10 mg/kg), oral dipyrone (15 mg/kg) or intramuscular dipyrone (15 mg/kg). The primary outcome was mean temperature reduction after 30, 45, 60, 90 and 120 minutes. Secondary outcomes were fever-associated symptoms and clinical adverse events.

RESULTS

Fever decreased by about 0.5 degrees C after 45 minutes and by about 1.0 degrees C after 120 minutes in all three groups. Mean temperatures were similar for the three groups at all times. There was a significant decrease in fever-associated symptoms for all groups. Six patients (four receiving oral dipyrone and two receiving ibuprofen) were withdrawn because of vomiting within 20 minutes after first dose of study medication. One patient assigned to oral ibuprofen presented transient urticaria.

CONCLUSIONS

Antipyretic efficacy and tolerability were similar for oral ibuprofen, oral dipyrone and intramuscular dipyrone. Oral antipyretics seem more appropriate for feverish children.

Analgesia pós-operatória

JUSTIFICATIVAS E OBJETIVOS: A dor sempre foi uma das maiores preocupações do homem, entretanto, apesar dos progressos da ciência, ainda existem várias barreiras ao seu adequado tratamento, incluindo a falta de conhecimento por parte da equipe médica, sobre o mecanismo das diversas drogas e técnicas empregadas. O objetivo deste trabalho é abordar as principais drogas e técnicas empregadas no controle da dor pós-operatória, visando estimular o interesse sobre o assunto bem como aumentar a eficácia do tratamento dado aos pacientes. CONTEÚDO: Está ressaltada neste artigo, a importância da adequada analgesia pós-operatória, considerando as principais drogas e técnicas utilizadas no controle da dor, seus mecanismos de ação, posologias, vias de administração e efeitos colaterais, bem como a importância da integração de toda a equipe envolvida nos cuidados do paciente para o sucesso do tratamento. O tratamento inadequado da dor no pós-operatório não se justifica, pois há um arsenal considerável de drogas e técnicas analgésicas. O que se faz necessário, portanto, é que toda equipe, anestesistas, cirurgiões, e enfermeiros tenham conhecimento e estejam integrados na utilização deste arsenal.

[Study of the extent and rate of bioavailability of ibuprofen tablets]

The extent and rate of bioavailability of ibuprofen tablets were determined in a crossover clinical trial in 18 healthy subjects of both sexes. The study was approved by the local ethical committee and was authorized by the Spanish Medicines Agency. Volunteers signed an informed consent form and were included in accordance with the standard procedures for this type of study. In two distinct sessions participants received a single 600 mg ibuprofen dose as Gelofeno(®) 600 mg tablets (Laboratorios Gelos S.L.), or as the reference formulation, Neobrufen(®) 600 mg tablets. Ibuprofen concentrations in plasma were determined immediately before (0 h) and 0.25, 0.5, 0.75, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 10, 12 and 24 h after drug administration. The pharmacokinetic parameters were then calculated. In all subjects, Gelofeno(®) 600 mg tablets produced plasma concentrations above the quantification limit between 15 and 30 minutes after administration, and in 9 (50%) of these subjects maximal plasma concentrations were reached at 1 h. The median t(max) was 1.25 h, and the average maximal plasma concentration was 40.7 mg/l. Gelofeno(®) 600 mg tablets were bioequivalent both in extent and in rate of bioavailability compared with the reference drug. The formulation showed good tolerability and no medication-related adverse effects were observed.

Postoperative Schmerztherapie nach Tonsillektomie im Kindesalter

OBJECTIVE

We investigated the efficacy and side-effects of a concept for pain therapy after tonsillectomy in children.

PATIENTS AND METHODS

A total of 100 children aged between 6 and 14 years were treated according to the following protocol for pain therapy after tonsillectomy: after induction of anaesthesia the children received 35-40 mg/kg acetaminophen rectally and 0.1 mg/kg piritramide i.v.. Additionally, boluses of 0.05 mg/kg pitritramide i.v. were allowed in the recovery room and 2 doses of 20 mg/kg acetaminophen were given rectally every 6 h on the day of surgery. On the following day the children received 30 mg/kg acetaminophen 3 times per day and from the second postoperative day onwards 1 mg/kg diclofenac was given 3 times a day. The rescue therapy was 5 mg/kg metamizol orally. The severity of the postoperative pain was evaluated by a visual pain scale (VAS) (0-100), side-effects such as vomiting and postoperative haemorrhage were documented. The Friedman test was used for testing the time course of pain intensity.

RESULTS

The median of the VAS was 42 on the day of surgery, 35 on the first postoperative day and fell continuously to 10 by the 6th postoperative day. The decrease of pain severity was statistically significant (p <0.05). A rescue therapy was necessary in 6 patients on the day of surgery and in 9 patients on the first postoperative day. 7 patients suffered a postoperative haemorrhage, 4 out of the 7 needed a surgical revision and 2 out of 100 patients vomited.

CONCLUSION

We conclude that this protocol for pain therapy after tonsillectomy was effective. The incidence of postoperative haemorrhage and vomiting was low.

[Antipyretic effectiveness of ibuprofen and paracetamol]

OBJECTIVE

To compare the antipyretic effectiveness of ibuprofen and paracetamol and to evaluate the possible influence of patients' sex, weight, height and underlying disease on effectiveness.

PATIENTS AND METHODS

A total of 166 children with fever, defined as a temperature equal to or above 38 degrees C, were enrolled. Of these, 80 were given paracetamol at a dose of 15 mg per kg and 86 were given 7 mg of ibuprofen per kg. Temperature was recorded at 60, 120,180 and 240 minutes after drug administration. Data were statistically analyzed, including analysis of paired data.

RESULTS

Ninety percent of the children became afebrile at some time during the study with both paracetamol and ibuprofen. Seventy-four percent of the patients remained afebrile 4 hours after drug administration. The mean temperatures obtained with ibuprofen versus paracetamol were 37.66 +/- 0.73 vs 37.8 +/- 0.65, p = 0.22 one hour after drug administration; 37.09 +/- 0.83 vs 37.29 +/- 0.71, p = 0.14 two hours after drug administration; 37.12 +/- 1.05 vs 37.28 +/- 0.87, p = 0.64 three hours after drug administration; and 37.40 +/- 1.12 vs 37.46 +/- 1.00, p = 0.72 four hours after drug administration. The maximum rate of temperature decrease was achieved during the first 60 minutes after drug administration (-1.32 +- 0.83 with ibuprofen vs -1.09 +/- 0.77 with paracetamol, p = 0.10). In children aged between 5 and 12 years, ibuprofen achieved significantly lower temperatures than paracetamol (38.00 +/- 0.65 vs 37.45 +/- 0.43, p = 0.02 at 1 hour; 36.71 +/- 0.66 vs 37.60 +/- 0.93, p = 0.01 at 2 hours; 36.80 +/- 0.79 vs 37.67 +/- 1.12, p = 0.03 at 3 hours). Analysis by weight, height or underlying disease revealed no significant differences.

CONCLUSIONS

Both ibuprofen and paracetamol proved to be successful in reducing temperature. The effectiveness of ibuprofen and paracetamol was similar, except in children aged more than 5 years old, in whom ibuprofen was more effective. Weight, sex and underlying disease had no influence on effectiveness.

Characterization of the role of physicochemical factors on the hydrolysis of dipyrone

Dipyrone is a prodrug which is used mainly for its analgesic and antipyretic effects. After oral intake, dipyrone is rapidly hydrolyzed to its main metabolite, 4-methylaminoantipyrine (4-MAA), from which many other metabolites are produced by enzymatic reactions. Even though it is well known that dipyrone is a prodrug and hydrolyzed non-enzymatically, in most of the studies of dipyrone the prodrug form is tested using in vitro methodologies, which do not represent or predict the actual in vivo activity of dipyrone. In this study, we characterize the hydrolysis kinetics of dipyrone as functions of concentration, temperature, and pH using a HPLC assay. Concentration is an important factor in the hydrolysis of dipyrone. Low concentrations of dipyrone are hydrolyzed more rapidly than are solutions of higher concentrations. At a concentration of 0.1M, which is 140 times, the concentration of the marketed pharmaceutical form, dipyrone is only minimally (10%) hydrolyzed to 4-MAA at 5h. Temperature, as expected, affects the hydrolysis reaction dramatically. We tested three temperatures (4, 21, and 37 degrees C) and found that at body temperature the hydrolysis is significantly faster than at room or at refrigerator temperatures. Compared with more alkaline solutions, the hydrolysis rate of dipyrone increases dramatically in acidic solutions. At low pH (2.5) and at a 0.01 mM concentration, the hydrolysis of dipyrone is completed within almost 30 min, which is the highest rate we observed. Experiments which involve in vitro and/or local application of dipyrone should consider these physicochemical factors and interpret the results accordingly.

Antipyretic efficacy and safety of ibuprofen and acetaminophen in children

OBJECTIVE

To evaluate the antipyretic effects and safety of ibuprofen compared with acetaminophen in febrile children.

DATA SOURCES

Searches of MEDLINE (1966-November 2003) and EMBASE (1988-November 2003) were conducted using the terms ibuprofen and acetaminophen. Bibliographies of selected articles were reviewed.

DATA SYNTHESIS

Ibuprofen was significantly more effective than acetaminophen in reducing fever after a single dose. Ibuprofen was found to be more effective after 6 hours, but not after a longer period of time. Studies with multiple doses have also failed to show that one drug is better than the other.

CONCLUSIONS

The efficacy and effectiveness of acetaminophen and ibuprofen in their recommended dosages are similar, with slightly more beneficial effects shown with ibuprofen.

Text Influenced Molecular Indexing (TIMI): a literature database mining approach that handles text and chemistry

We present an application of a novel methodology called Text Influenced Molecular Indexing (TIMI) to mine the information in the scientific literature. TIMI is an extension of two existing methodologies: (1) Latent Semantic Structure Indexing (LaSSI), a method for calculating chemical similarity using two-dimensional topological descriptors, and (2) Latent Semantic Indexing (LSI), a method for generating correlations between textual terms. The singular value decomposition (SVD) of a feature/object matrix is the fundamental mathematical operation underlying LSI, LaSSI, and TIMI and is used in the identification of associations between textual and chemical descriptors. We present the results of our studies with a database containing 11,571 PubMed/MEDLINE abstracts which show the advantages of merging textual and chemical descriptors over using either text or chemistry alone. Our work demonstrates that searching text-only databases limits retrieved documents to those that explicitly mention compounds by name in the text. Similarly, searching chemistry-only databases can only retrieve those documents that have chemical structures in them. TIMI, however, enables search and retrieval of documents with textual, chemical, and/or text- and chemistry-based queries. Thus, the TIMI system offers a powerful new approach to uncovering the contextual scientific knowledge sought by the medical research community.