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Copyright ©2008 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458
All rights reserved.
Focus on Pharmacology, First EditionBy Jahangir Moini
Focus on PharmacologyEssentials for Health
Professionals
Chapter 30Pediatrics
Jahangir Moini, MD, MPH
Copyright ©2008 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458
All rights reserved.
Focus on Pharmacology, First EditionBy Jahangir Moini
Terms
• Neonate: birth to 28 days • Infant: 29 days to walking age (typically
1 year)• Toddler: 1 to 3 years of age
Copyright ©2008 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458
All rights reserved.
Focus on Pharmacology, First EditionBy Jahangir Moini
Factors that Affect Pharmacokinetics in Children
• Drugs inactivated by low pH gastric contents should not be given orally.
• Peristalsis is irregular and slower.• Rate of gastric emptying is variable.
Copyright ©2008 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458
All rights reserved.
Focus on Pharmacology, First EditionBy Jahangir Moini
Physiologic Impacts on Pharmacokinetics
The physiologic processes that influence pharmacokinetics in children include: – GI function– Tissue blood flow– Body fluid levels– Plasma protein concentrations– Liver function– Renal function.
Copyright ©2008 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458
All rights reserved.
Focus on Pharmacology, First EditionBy Jahangir Moini
Drug Distribution in Children
• Neonates have higher total body water than adults.
• Body fat is about 15%.• Protein binding of drugs is lower in
neonates.
Copyright ©2008 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458
All rights reserved.
Focus on Pharmacology, First EditionBy Jahangir Moini
Drug Absorption in Children
• Physiologic conditions can reduce rate of blood flow to site of administration: heart failure, cardiovascular shock, vasoconstriction
• If peripheral blood circulation improves, sudden increase of circulating drugs may cause toxic drug concentrations.
Copyright ©2008 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458
All rights reserved.
Focus on Pharmacology, First EditionBy Jahangir Moini
Drug Metabolism in Children
• Neonates exhibit substantially lower drug-metabolizing activities of oxidases and conjugating enzymes
• Dose-response relationships of some drugs may change markedly during first few weeks after birth
Copyright ©2008 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458
All rights reserved.
Focus on Pharmacology, First EditionBy Jahangir Moini
Drug Elimination in Children
• Glomerular filtration rate is lower in neonates.
• Drugs that require renal function for elimination are removed from the body very slowly during first weeks of life.
Copyright ©2008 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458
All rights reserved.
Focus on Pharmacology, First EditionBy Jahangir Moini
Limited Clinical Studies
• Very few clinical drug studies are done in children.
• Little data on effects of drugs in this population.
• Efficacy and dosage difficult to establish.
Copyright ©2008 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458
All rights reserved.
Focus on Pharmacology, First EditionBy Jahangir Moini
Pediatric Dosage Forms
• Elixirs: alcoholic solutions that offer consistent dissolution and distribution of drugs
• Suspensions: contain undissolved drug particles; must be shaken to evenly distribute drug particles
Copyright ©2008 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458
All rights reserved.
Focus on Pharmacology, First EditionBy Jahangir Moini
Drug Safety During Lactation
If data are not available about a certain drug and its effects on breastfeeding, the mother should not take it.
Copyright ©2008 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458
All rights reserved.
Focus on Pharmacology, First EditionBy Jahangir Moini
Pediatric Pharmacokinetic Differences
The differences in pharmacokinetics can lead to stronger or weaker drug effects in children compared with those of young adults.
Copyright ©2008 by Pearson Education, Inc.Upper Saddle River, New Jersey 07458
All rights reserved.
Focus on Pharmacology, First EditionBy Jahangir Moini
Pediatric Drug Doses
• Based on proportionally reduced adult doses
• Based on body surface area, age, or body weight
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