Related Experiment Video

Updated: Aug 24, 2026

Quantification of the Immunosuppressant Tacrolimus on Dried Blood Spots Using LC-MS/MS
08:38

Quantification of the Immunosuppressant Tacrolimus on Dried Blood Spots Using LC-MS/MS

Published on: November 8, 2015

Diclofenac and metabolite pharmacokinetics in children

Caroline D van der Marel1, Brian J Anderson, Janne Rømsing

  • 1Department of Paediatric Surgery, ErasmusMC-Sophia Rotterdam, The Netherlands.

Paediatric Anaesthesia
|May 22, 2004
PubMed

Insights

Rectal diclofenac (suppository) is a suitable option for children aged 2-8 years, offering higher bioavailability and faster absorption than enteric-coated tablets. This formulation is effective for postoperative pain management following short-term surgeries.

Area of Science:

  • Pharmacokinetics and Drug Metabolism
  • Pediatric Pharmacology
  • Pain Management

Background:

  • Limited data exist on diclofenac metabolism in children, particularly after rectal administration.
  • Previous studies focused on intravenous and enteric-coated oral diclofenac formulations in pediatric populations.

Purpose of the Study:

  • To investigate the pharmacokinetics of diclofenac and its hydroxyl metabolites following rectal administration in children.
  • To compare the relative bioavailability of rectal diclofenac suppositories with enteric-coated oral tablets.

Main Methods:

  • Twenty-six infants undergoing tonsillectomy received diclofenac suppositories (2 mg.kg(-1) followed by 1 mg.kg(-1) at 8 hours).
  • Serum concentrations of diclofenac, 4'-hydroxydiclofenac, and 5'-hydroxydiclofenac were measured post-administration.
  • Nonlinear mixed-effects models were used to estimate formation clearances and pharmacokinetic parameters; relative bioavailability was assessed against published data.

Main Results:

  • The formation clearance of 4'-hydroxydiclofenac was 8.41 L.h(-1) and 5'-hydroxydiclofenac was 3.41 L.h(-1) (standardized to 70 kg).
  • The diclofenac suppository formulation exhibited an absorption half-life of 0.613 h with a lag time of 0.188 h.
  • Relative bioavailability of the suppository compared to enteric-coated tablets was 1.26, with an earlier Tmax (50 min vs. 108 min).

Conclusions:

  • Rectal administration of diclofenac is a suitable route for children aged 2-8 years.
  • The suppository formulation demonstrates superior bioavailability and faster absorption compared to enteric-coated tablets.
  • Diclofenac suppositories are a viable option for postoperative analgesia in pediatric patients undergoing short-duration surgical procedures.
Abstract

More Related Videos

Mass Spectrometry and Luminogenic-based Approaches to Characterize Phase I Metabolic Competency of In Vitro Cell Cultures10:44

Mass Spectrometry and Luminogenic-based Approaches to Characterize Phase I Metabolic Competency of In Vitro Cell Cultures

Published on: March 28, 2017

Related Concept Videos

Pharmacokinetics in Pediatric Patients: Drug Metabolism01:24

Pharmacokinetics in Pediatric Patients: Drug Metabolism

In pediatric care, understanding the nuances of hepatic drug metabolism is crucial, as it significantly differs from that of adults. This divergence is primarily due to the developmental stage of drug-metabolizing enzymes, which affects how medications are processed in the body. In neonates, for instance, the activity of Phase I enzymes—critical for the initial breakdown of drugs—is markedly reduced, functioning at just 20–40% of the levels seen in adults. This reduction poses a challenge in...
Pharmacokinetics in Pediatric Patients: Drug Excretion01:26

Pharmacokinetics in Pediatric Patients: Drug Excretion

In pediatric medicine, understanding the renal function and drug elimination nuances is crucial for administering safe and effective treatments. Newborns, in particular, display markedly slower renal functions than adults, profoundly affecting how drugs are cleared from their bodies. This slower drug clearance requires clinicians to extend the dosing intervals for many medications to prevent drug accumulation and toxicity while ensuring therapeutic efficacy.One key area where these adjustments...
Pharmacokinetics in Pediatric Patients: Drug Distribution01:17

Pharmacokinetics in Pediatric Patients: Drug Distribution

Drug distribution in the pediatric population exhibits unique challenges and considerations due to the physiological differences between children, particularly neonates and infants, and adults. A crucial aspect of pediatric pharmacology is understanding how these differences impact the pharmacokinetics of various drugs, necessitating age-specific dosing strategies to ensure efficacy and safety.Neonates and infants have a higher total body water content, ~75%–90% of their body weight, compared...
Pharmacokinetics in Pediatric Patients: Overview and Drug Absorption01:23

Pharmacokinetics in Pediatric Patients: Overview and Drug Absorption

Understanding the physiological differences in the pediatric population is crucial for effective pharmacotherapy. Neonates, infants, and children exhibit significant variations in gastric pH, gastric emptying time, intestinal transit time, and biliary function. These variations profoundly affect oral drug absorption, necessitating a nuanced approach to pediatric dosing.Neonates present with a unique physiological profile, having a gastric pH greater than 4 and faster and more irregular gastric...
Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Metabolism01:18

Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Metabolism

Geriatric patients show significant variation in how their bodies process medications, which can change how effective and safe treatments are. The liver is the primary organ where drug metabolism occurs, involving two main types of chemical reactions: phase I and II. Phase I metabolism is driven by the cytochrome P450 enzyme system, which includes key types such as CYP3A, CYP2D6, and CYP2C9. Research indicates that while aging doesn't notably alter the levels or activity of these enzymes, it...
Drug Dosing: Infants and Children01:29

Drug Dosing: Infants and Children

Pediatric patient dosages diverge from adults due to disparities in body surface area, total body water, and extracellular fluid per kilogram of body weight. The dosing regimen considers the variations in pharmacokinetics and pharmacology across distinct age groups, encompassing preterm newborns, infants, young children, older children, and adolescents. Calculation of pediatric patient doses is predicated on determining body surface area, which exhibits a superior correlation with the child's...