Pharmacokinetics of ketoprofen syrup in small children

Efficacy and Safety of NSAIDs in Infants: A Comprehensive Review of the Literature of the Past 20 Years

Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used in infants, children, and adolescents worldwide; however, despite sufficient evidence of the beneficial effects of NSAIDs in children and adolescents, there is a lack of comprehensive data in infants. The present review summarizes the current knowledge on the safety and efficacy of various NSAIDs used in infants for which data are available, and includes ibuprofen, dexibuprofen, ketoprofen, flurbiprofen, naproxen, diclofenac, ketorolac, indomethacin, niflumic acid, meloxicam, celecoxib, parecoxib, rofecoxib, acetylsalicylic acid, and nimesulide. The efficacy of NSAIDs has been documented for a variety of conditions, such as fever and pain. NSAIDs are also the main pillars of anti-inflammatory treatment, such as in pediatric inflammatory rheumatic diseases. Limited data are available on the safety of most NSAIDs in infants. Adverse drug reactions may be renal, gastrointestinal, hematological, or immunologic. Since NSAIDs are among the most frequently used drugs in the pediatric population, safety and efficacy studies can be performed as part of normal clinical routine, even in young infants. Available data sources, such as (electronic) medical records, should be used for safety and efficacy analyses. On a larger scale, existing data sources, e.g. adverse drug reaction programs/networks, spontaneous national reporting systems, and electronic medical records should be assessed with child-specific methods in order to detect safety signals pertinent to certain pediatric age groups or disease entities. To improve the safety of NSAIDs in infants, treatment needs to be initiated with the lowest age-appropriate or weight-based dose. Duration of treatment and amount of drug used should be regularly evaluated and maximum dose limits and other recommendations by the manufacturer or expert committees should be followed. Treatment for non-chronic conditions such as fever and acute (postoperative) pain should be kept as short as possible. Patients with chronic conditions should be regularly monitored for possible adverse effects of NSAIDs.

Comparison of acetaminophen and ketoprofen in febrile children: a single dose randomized clinical trial

OBJECTIVE

To compare ketoprofen with acetaminophen in febrile children in terms of proportion of achieved temperatures below 37.8°C and time of temperature reduction.

METHODS

316 patients (6 months-12 years) with fever were randomly assigned to receive a single dose of acetaminophen or ketoprofen orally. Tympanic temperature was measured at the time of antipyretic administration and at 15, 30, 60, 120,180, 240 min thereafter.

RESULTS

A higher proportion of patients in the ketoprofen group achieved a temperature below 37.8°C during the 4 h follow up (95% CI, 3.03-12.99, p < 0.001). Treatment with ketoprofen was more likely to achieve temperature below 37.8°C compared to acetaminophen with odds ratio 6.25. (95% CI, 3.03-12.99, p < 0.001). Ketoprofen was superior at temperatures ≥39°C (p < 0.001). Ketoprofen group showed significantly lower mean temperatures at times 15 min (95% CI, 0.95-3.36; P < 0.001), 30 min (95% CI, 3.87-6.59; P < 0.001), 60 min (95% CI, 6.99-10.14; P < 0.001), 120 min (95% CI, 1.66-5.49; P < 0.001), 180 min (95% CI, 0.47-5.73; p < 0.05), and 240 min (95% CI, 3.87-6.59; p < 0.05). The mean temperature reductions at times 15, 30 and 60 min were larger in ketoprofen group (p < 0.001). Ketoprofen was superior to acetaminophen for less time with fever in the first 4 h (p < 0.001).

CONCLUSIONS

It seems reasonable to use ketoprofen first in need of rapid fever reduction.

Ketoprofen pharmacokinetics, efficacy, and tolerability in pediatric patients

The NSAID ketoprofen is used widely in the management of inflammatory and musculoskeletal conditions, pain, and fever in children and adults. Pharmacokinetic studies show that drug exposure after a single intravenous dose is similar in children and adults (after dose normalization), and thus similar mg/kg bodyweight dosing may be used in children and adults. Ketoprofen crosses the blood-brain barrier and therefore has the potential to cause central analgesic effects. Ketoprofen has been investigated in children for the treatment of pain and fever, peri- and postoperative pain, and inflammatory pain conditions. The results of four clinical trials in febrile conditions with the oral syrup formulation indicate that ketoprofen is as effective as acetaminophen (paracetamol) and ibuprofen, allowing children to rapidly return to daily activities with improvements in sleep quality and appetite. Studies of ketoprofen in the management of postoperative pain indicate that ketoprofen is a highly effective analgesic when administered perioperatively for a variety of surgical types, by a variety of routes, and whether given preoperatively or postoperatively. For adenoidectomy, intravenous ketoprofen provided superior postoperative analgesic efficacy compared with placebo. Analgesic efficacy was similar with intravenous, intramuscular, or rectal routes of administration, but oral administration just before surgery was inferior to intravenous administration in this setting. In patients undergoing a tonsillectomy, intravenous ketoprofen was superior to intravenous tramadol in terms of the need for postoperative rescue analgesia, but did not remove the need for rescue opioid therapy in these patients. Intravenous ketoprofen had superior postoperative analgesic efficacy to placebo when given as an adjuvant to epidural sufentanil analgesia after major surgery. Oral ketoprofen has shown efficacy in the treatment of juvenile rheumatoid arthritis. Ketoprofen is generally well tolerated in pediatric patients. Most of the adverse events reported are mild and transient, and are similar to those observed with other NSAIDs. Long-term tolerability has not yet been fully established in children, but data from three studies in >900 children indicate that oral ketoprofen is well tolerated when administered for up to 3 weeks after surgery. In conclusion, ketoprofen is effective and well tolerated in children for the control of post-surgical pain and for the control of pain and fever in inflammatory conditions.

Ketoprofen versus paracetamol (acetaminophen) or ibuprofen in the management of fever: results of two randomized, double-blind, double-dummy, parallel-group, repeated-dose, multicentre, phase III studies in children

Fever is a common symptom in children and one of the major concerns of parents of younger and preschool-age children. To compare the efficacy and safety of ketoprofen with that of paracetamol (acetaminophen) and ibuprofen in the treatment of febrile conditions in children. Two prospective, randomized, double-blind, double-dummy, repeated-dose, multicentre, phase III studies with two parallel groups in each study were conducted in primary-care outpatient clinics. Children aged 6 months to 6 years presenting with a febrile condition and an oral body temperature of > or =38.8 degrees C or rectal temperature of > or =39 degrees C were eligible for inclusion. Patients were randomized to receive either ketoprofen syrup 0.5 mg/kg, ibuprofen suspension 5 mg/kg or paracetamol suspension 15 mg/kg every 6 hours by the oral route. The primary outcome measure was the change in temperature at 3 hours (H3), compared with baseline (H0). All three treatments provided similar mean maximum decreases of 1.4-1.5 degrees C in body temperature at H3 compared with H0. Use of ketoprofen was not associated with any increased risk of adverse events compared with the two reference compounds. Ketoprofen 0.5 mg/kg appeared to be equivalent to the standard antipyretic doses of the reference products ibuprofen 5 mg/kg and paracetamol 15 mg/kg. Ketoprofen at the 0.5 mg/kg dose should be an effective and safe option for symptomatic management of fever in children.

Dose-finding studies of ketoprofen in the management of fever in children: report on two randomized, single-blind, comparator-controlled, single-dose, multicentre, phase II studies

BACKGROUND

Ketoprofen is a highly effective NSAID with antipyretic and analgesic properties for the symptomatic management of pain and fever in both adults and children.

OBJECTIVE

To compare three dose levels of ketoprofen with paracetamol (acetaminophen) in the management of fever in children.

METHODS

Two prospective, randomized, single-blind, comparator-controlled, single-dose, multicentre, phase II studies with four parallel groups in each study were conducted in primary-care outpatient clinics. Children aged 6-24 months and 2-6 years presenting with a febrile condition (rectal body temperature > or =39 degrees C) were included in the studies. Patients were treated with either ketoprofen syrup 0.25 mg/kg, 0.5 mg/kg or 1 mg/kg, or paracetamol drinkable solution 15 mg/kg, both administered orally. The primary outcome measure was the maximal reduction in body temperature before re-medication compared with baseline during the 6-hour study period.

RESULTS

In the ketoprofen groups, the mean maximal temperature decreases in the younger/older age groups were 1.6/1.6 degrees C, 2.0/1.9 degrees C and 1.9/2.2 degrees C with doses of 0.25 mg/kg, 0.5 mg/kg and 1 mg/kg of ketoprofen, respectively, compared with 1.8/1.8 degrees C with paracetamol 15 mg/kg. In the older children, ketoprofen provided antipyretic efficacy in a dose-dependent manner.

CONCLUSION

Ketoprofen was found to have a significant antipyretic efficacy in children. The lowest dose of ketoprofen syrup that provided a meaningful antipyretic effect in both groups was 0.5 mg/kg. At this dose the antipyretic efficacy was equal to that of paracetamol 15 mg/kg. Based on these data, a dose of 0.5 mg/kg of ketoprofen was selected for future evaluation in phase III studies in the symptomatic management of fever in children.

Antipyretic effect of ketoprofen

OBJECTIVE

The aim of this study was to investigate the efficacy and side effect profile of ketoprofen as well as compliance with respect to the taste of the drug and compare these parameters with those of acetaminophen and ibuprofen.

METHODS

A total of 301 patients between 1-14 years of age who applied to emergency rooms of three medical centers with the complaint of fever that required antipyretic therapy were included in the study. Fever was measured with the aid of a tympanic thermometer (Braun Kronberg 6014) and followed for 4-6 hours. The measurement was repeated at 30, 60, 120 minutes, and again 4-6 hours after the initial assessment.

RESULTS

The mean age of the patients was 47.8+/-41.1 months. The patients randomly received 15 mg/kg/dose of acetaminophen (n=112 group 1), 0.5 mg/kg/dose of ketoprofen (n=105, group 2), or 10 mg/kg/dose of ibuprofen (n=84, group 3). Fever was 38.4+/-0.7 degrees C, 38.4+/-0.7 degrees C, and 38.5+/-0.5 degrees C at 30 minutes; 38.0+/-0.7 degrees C, 37.9+/-0.7 degrees C, and 38.0+/-0.6 degrees C at 60 minutes (p>0.05), 37.7+/-0.6 degrees C, 37.6+/-0.7 degrees C, and 37.7+/-0.5 degrees C at 120 minutes (p>0.05); 37.5+/-0.7 degrees C, 37.3+/-0.6 degrees C, and 37.4+/-0.6 degrees C at 4-6 hours after admission (p>0.05). The fever was significantly lower at 30, 60, and 120 minutes in all group s (p<0.05). Early vomiting after medication (<6 hours) was observed in 3.8%, 13.5%, and 9.6% whereas late vomiting (6-48 hours) occurred in 1.3%, 2.7%, and 5.8% respectively (p>0.05). Bad taste was expressed by 5.1%, 12.2%, and 5.8% early (<6 hours), and 3.9%, 8.1%, and 3.8% late (6-48 hours) (p>0.05). There were no differences between age groups for antipyretic effect, taste and adverse effect in three drugs (p>0.05).

CONCLUSION

All three drugs were similar in terms of efficacy, adverse effects, and compliance within 48 hours of therapy. These results suggest that ketoprofen may be used for antipyresis as an alternative to acetaminophen and ibuprofen.

Postoperative pain control in children: a guide to drug choice

Postoperative pain in children can usually be well controlled with a combination of analgesics, including acetaminophen (paracetamol), NSAIDs, opioids, and local/regional anesthesia. Recent research has shown that the dosage of acetaminophen required to provide analgesia is higher than the traditional dosages used for the regulation of elevated body temperature. Rectal administration of acetaminophen gives a lower and more variable bioavailability compared with oral administration. There is growing experience with the use of NSAIDs in children and several studies have demonstrated the relatively strong analgesic potential of these drugs. Titration of opioids to analgesic effect, and the use of nurse- and patient-controlled continuous opioid infusions in children have gained widespread use and, with proper education and supervision, are considered excellent methods of pain control. Local peripheral and central blocks decrease the need for anesthetics during surgery and provide effective postoperative pain relief.

Pharmacokinetics of Oxycodone After Intravenous, Buccal, Intramuscular and Gastric Administration in Children

OBJECTIVE

To evaluate the pharmacokinetics of four administration routes of oxycodone parenteral liquid (10 mg/mL), single intravenous and intramuscular injections and buccal and gastric administration, in children.

PATIENTS AND PARTICIPANTS

Forty generally healthy children, aged 6-93 months, undergoing inpatient surgery.

METHODS

After induction of anaesthesia, children received a single dose of oxycodone 0.1 mg/kg intravenously (n = 9), intramuscularly (n = 10), buccally (n = 11) or via an orogastric tube into the stomach (n = 10). Regular blood samples were collected up to 12 hours, and plasma was analysed for oxycodone using gas chromatography-mass spectrometry (limit of quantification 1 microg/L).

RESULTS

The peak drug concentration observed was 57-110 (mean 82) microg/L after intravenous administration, 23-54 (34) microg/L after intramuscular administration, 3.9-14 (9.8) microg/L after buccal administration and 1.7-15 (9.2) microg/L after gastric administration. The time to peak concentration was 2-30 (16) minutes in the intramuscular group, 30-480 (221) minutes in the buccal group and 60-360 (193) minutes in the gastric group. The terminal elimination half-lives were closely similar in the four groups: 124-208 (163) minutes in the intravenous group, 162-227 (150) minutes in the intramuscular group, 73-234 (150) minutes in the buccal group and 80-246 (147) minutes in the gastric group. Area under the concentration-time curve (AUC) was 5037-8954 (6612) microg x min/L in the intravenous group, 3084-5524 (4473) microg x min/L in the intramuscular group, 1444-5560 (3658) microg x min/L in the buccal group and 692-3843 (2436) microg x min/L in the gastric group. The estimated bioavailability (AUC/mean intravenous AUC) of intramuscular oxycodone was 0.47-0.84 (0.68), that of buccal oxycodone 0.22-0.84 (0.55) and that of gastric oxycodone 0.10-0.58 (0.37).

CONCLUSION

The pharmacokinetics of intravenous oxycodone in children aged 6-93 months are fairly similar to those reported in adults. Intramuscular administration provides relatively constant drug absorption, but after buccal and gastric administration the interindividual variation in the rate and extent of absorption is large.

Pharmacokinetics of intravenous and rectal ketoprofen in young children

OBJECTIVE

To evaluate the relative bioavailabilities of ketoprofen after intravenous and rectal administration to young children.

DESIGN

Open-label prospective parallel-group study.

PATIENTS

Participants were 28 children aged 7 to 93 months.

METHODS

Eighteen children received a single intravenous injection of ketoprofen 1 mg/kg, and ten children, weight 16-24 kg, received a 25mg ketoprofen suppository. Venous blood samples were collected at selected times after administration, ranging from 2 minutes to 8 hours for the intravenous group and from 30 minutes to 8 hours for the suppository group. A validated high performance liquid chromatography method was used to measure plasma ketoprofen concentrations.

RESULTS

In the intravenous group, the maximum plasma concentration of ketoprofen ranged between 10.5 and 22.2 mg/L, and in the suppository group, following dose normalisation to 1 mg/kg of ketoprofen, between 3.8 and 7.4 mg/L. In the intravenous group, area under the concentration-time curve from zero to infinity ranged between 9.2 and 23.5 mg x h/L, and in the suppository group after dose normalisation between 8.8 and 12.9 mg x h/L. The bioavailability of ketoprofen from the suppository was about 73%. Volume of distribution was 0.04-0.10 L/kg in the intravenous group and 0.08-0.16 L/kg in the suppository group. The terminal half-life was comparable in both study groups, ranging between 0.7 and 3.0 hours in the intravenous group and between 1.2 and 2.9 hours in the suppository group.

CONCLUSION

Absorption of ketoprofen after rectal administration is reasonably rapid and predictable. Because the bioavailability of rectal ketoprofen is also relatively high, a suppository may be used in children in whom the drug cannot be given intravenously or by mouth.

Nonsteroidal anti-inflammatory drugs for postoperative pain: a focus on children

Pain is a common symptom after surgery in children, and the need for effective pain management is obvious. For example, after myringotomy, despite the brief nature of the procedure, at least one-half of children have significant pain. After more extended surgery, such as tonsillectomy, almost all children have considerable pain longer than 7 days. Nonsteroidal anti-inflammatory drugs (NSAIDs) are useful for postoperative pain management because surgery causes both pain and inflammation. Several pediatric studies indicate NSAIDs are effective analgesics in the management of mild and moderate pain. In the treatment of severe pain, NSAIDs should be given with acetaminophen (paracetamol) or opioids, and the use of an appropriate regional analgesic technique should be considered. NSAIDs are more effective in preventing pain than in the relief of established pain. Pain following surgery is best managed by providing medication on a regular basis, preventing the pain from recurring. This proactive approach should be implemented for any procedure where postoperative pain is the likely outcome. In children, the choice of formulation can be more important than the choice of drug. Intravenous administration is preferred for children with an intravenous line in place; thereafter mixtures and small tablets are feasible options. Children dislike suppositories, and intramuscular administration should not be used in nonsedated children. Ibuprofen, diclofenac, ketoprofen and ketorolac are the most extensively evaluated NSAIDs in children. Only a few trials have compared different NSAIDs, but no major differences in the analgesic action are expected when appropriate doses of each drug are used. Whether NSAIDs differ in the incidence and severity of adverse effects is open to discussion. Because NSAIDs prevent platelet aggregation they may increase bleeding. A few studies indicate that ketorolac may increase bleeding more so than other NSAIDs, but the evidence is conflicting. Severe adverse effects of NSAIDs in children are very rare, but it is important to know about adverse effects in order to recognize and treat them when they do occur. NSAIDs are contraindicated in patients in whom sensitivity reactions are precipitated by aspirin (acetylsalicylic acid) or other NSAIDs. They should be used with caution in children with liver dysfunction, impaired renal function, hypovolemia or hypotension, coagulation disorders, thrombocytopenia, or active bleeding from any cause. In contrast, it seems that most children with mild asthma may use NSAIDs.

Diffusion of ketoprofen into the cerebrospinal fluid of young children

BACKGROUND

The objective was to examine whether or not ketoprofen enters the cerebrospinal fluid after a single oral dose of 1 mg.kg-1 syrup, and to find out what is the lowest plasma concentration that will achieve a measurable level in the cerebrospinal fluid.

METHODS

We measured ketoprofen concentrations both in plasma and cerebrospinal fluid of 10 young and healthy children (aged 9-86 months) after surgery with spinal anaesthesia. Samples of cerebrospinal fluid were collected 30 min after drug administration, at the same time as venous blood samples. A validated high-performance liquid chromatography method with a lower limit of 0.02 microg x ml(-1) was used to detect ketoprofen concentrations in cerebrospinal fluid and plasma.

RESULTS

Ketoprofen was detectable in the cerebrospinal fluid only in the child who had the highest plasma concentration, 7.4 microg x ml(-1), while at plasma concentrations 6.5 microg x ml(-1) or less, cerebrospinal fluid (CSF) concentrations remained unmeasurable. The detected CSF/plasma ratio was 0.008.

CONCLUSIONS

These results indicate that ketoprofen at a dose of 1 mg x kg(-1) is too low to produce measurable CSF levels within 30 min of oral administration.

Risks and benefits of nonsteroidal anti-inflammatory drugs in children: a comparison with paracetamol

Nonsteroidal anti-inflammatory drugs (NSAIDs) possess antipyretic, analgesic and anti-inflammatory effects. They are frequently used in children and have numerous therapeutic indications, the most common ones being fever, postoperative pain and inflammatory disorders, such as juvenile idiopathic arthritis (JIA) and Kawasaki disease. Their major mechanism of action is through inhibition of prostaglandin biosynthesis by blockade of cyclo-oxygenase (COX). The disposition of most NSAIDs has been mainly studied in infants > or = 2 years of age. Compared with adults, the volume of distribution and clearance of NSAIDs such as diclofenac, ibuprofen (infants aged between 3 months and 2.5 years), ketorolac and nimesulide were increased in children. The elimination half-life was similar in children to that in adults. These pharmacokinetic differences might be clinically significant with the need for higher loading and/or maintenance doses in children. Ibuprofen, acetylsalicylic acid (ASA) and acetaminophen are the most frequently used agents for fever reduction in children. Over the past 20 years, because of the association between ASA use and Reye's syndrome, most of the interest has been directed toward ibuprofen and acetaminophen. In view of its comparable antipyretic efficacy, but superior tolerability profile, acetaminophen, when used appropriately with age-adapted formulations, should remain the first-line therapy in the treatment of childhood fever. At the moment, there is no scientific evidence to recommend simultaneous use of these two antipyretic drugs. Most NSAIDs provide mild to moderate analgesia, with the exception of ketorolac which has a strong analgesic activity. The analgesic efficacy of ketorolac, ketoprofen, diclofenac and ibuprofen in the treatment of postoperative pain has been mainly studied following a single dose, in children of > or = 1 year of age undergoing minor surgeries. In this setting, when used either alone or in adjunct to caudal or epidural anaesthesia, they were associated with an opioid-sparing effect and were well tolerated. With the exception of ketorolac use in children undergoing tonsillectomy, where controversy exists regarding the risk of postoperative haemorrhage, NSAIDs have not been associated with an increased risk of perioperative bleeding. NSAIDs are the first-line therapy in JIA. They appear to be equally effective and tolerated, with the exception of ASA which is associated with more adverse effects. ASA has been used for many years in the treatment of Kawasaki disease and is part of the standard modality of treatment in combination with intravenous gammaglobulins. More recently, lung inflammation associated with cystic fibrosis (CF) has become a new target for NSAIDs. Despite promising preliminary results with ibuprofen, numerous questions need to be answered before this new strategy becomes part of the conventional treatment of patients with CF. In summary, NSAIDs are effective in reducing fever, alleviating pain and reducing inflammation in children, with a good tolerance profile. Pharmacokinetic studies are needed to characterise the disposition of NSAIDs in very young infants in order to use them rationally. To date, no studies have been published on the disposition, tolerability and efficacy of specific COX-2 inhibitors in children. Further clinical experience with these agents in adults is warranted before undergoing trials with specific COX-2 inhibitors in children.

Comparison of intravenous and oral ketoprofen for postoperative pain after adenoidectomy in children

One hundred children, aged 1-9 yr, undergoing adenoidectomy were randomized to receive ketoprofen 1 mg kg-1 either i.v. with an oral placebo (n = 40) or ketoprofen 1 mg kg-1 orally with an i.v. placebo (n = 40), or both oral and i.v. placebo (n = 20). The study design was prospective and double blind with parallel groups. The pain was assessed at rest and during swallowing using the Maunuksela pain scale (0 = no pain, 10 = worst possible pain) after surgery for 3 h. Fentanyl 0.5 microgram kg-1 i.v. was given for rescue analgesia. Children in the i.v. group needed significantly less doses (1, 1-3; median and 10th/90th percentiles) of rescue analgesic compared with the oral group (2, 1-3; P = 0.024). Of those who needed rescue analgesic, three out of 30 children in the i.v. group required three or more doses of fentanyl compared with 10 out of 28 children in the oral group. There were no differences between the groups with respect to pain scores, operation times, perioperative bleeding or frequency of adverse events.