This document discusses several key points regarding pediatric pharmacy practice:
- Children represent a significant portion of the global population but have poorly developed organ functions and are at higher risk for toxicity and adverse drug reactions. Historical events like the sulfanilamide elixir death and thalidomide tragedy demonstrate this risk.
- Pediatric patients require specialized pharmacist care due to age-related variability in drug absorption, distribution, metabolism, and excretion, as well as higher risk of dosing errors due to non-standard doses, need for compounding and dilutions, and less tolerance for mistakes.
- The roles of pediatric pharmacists include dosing calculations and consultations, medication history reviews, discharge counseling, drug
2. 20 to 25% of total world population
Poorly developed organ functions and highest
risk of toxicity and poor clinical response.
Sulphanilamide elixir- death: Thalidomide
tragedy.
Taste of
Raspberries, Taste
of Death
The 1937 Elixir
Sulfanilamide
Incident 2
3. Why Do We Need Paediatric
Pharmacists?
Children are at increased risk of adverse
drug events (ADE’s)
Pharmacologic factors
•Age-based variability in absorption,
distribution, metabolism, and excretion of
drugs
Physiologic factors
•Weight and/or body surface area (BSA)
need
to be considered for each drug for each
patient
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4. Process factors
•Individualized dilution of stock
medications
and fluids
•Multiple concentrations of same drug
• Dilution errors
Environmental factors
•ICU settingWeight-based dosing
Error dosing rate
Error rates inversely related to size or
weight of patient
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5. Paediatric medication orders are more
prone
to errors than adult orders
Doses are not standard
Math errors can occur when calculating
the dose
Suspensions often have to be compounded
Tablets may have to be cut
Dilutions need to be made to make
amounts that are measurable
However, children have less tolerance for
errors
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6. Preemie <37 weeks gestation (gestational
age is the time from conception
until
Birth)
Full Term 37-42 weeks gestation
Neonate First 30 days of life
Infant First year of life
Toddler From 1 to 2 years of life
Child Age 3-11
Adolescent Age Age 12 on
Definition of a child is based on age
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7. Special Challenges of Practicing in
Pediatrics
Lack of published information on
therapeutic uses and monitoring of drugs
Lack of FDA approval for many drugs used
in pediatrics
Lack of appropriate commercially available
dosage forms and concentrations of commonly
used medicationsInability of patients to communicate with
caregivers
Interacting with parents
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8. Skills Necessary
Dosage calculations
Dosage-form selection
Specialized drug preparation and
administration techniques
Understanding of PK/PD changes occurring
with age
Understanding of disease-specific
conditions
affecting drug choice or dose
Understanding nature of medication errors
in
pediatric patients 8
9. Role of the Paediatric Pharmacist
Ensure the patient receives the necessary
drug in a manner that allows the intended
therapeutic effect to be realized.
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10. Patient interviews
Medication history
•Inquiring about OTC and herbal
medications
Allergy history
•True allergic reaction?
Immunization history
•Can make recommendations to MD if
patient is not up-to-date on immunizations 10
11. Discharge counselling
Administration & use of appropriate
measuring device dosage
Preparation of form at home, if
necessary
Attention to taste of liquid medications
Prevention of accidental ingestions
School / day-care issues directed at
patient and/or caregiver
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12. Drug Information
Influence selection of drug therapy in initial
phase of patient care
•Consult with physician and patient
Provide current, unbiased and relevant drug
information
Assist with finding literature supporting use of
drugs for unlabeled indications
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13. Therapeutic Drug Monitoring
Understanding timing / indication of
monitoring to prevent unnecessary blood draws
on children
Account for age-related differences in
dosage
Documentation in patient chart
Monitor steps of the medication use
process
Reduce drug costs
Avoidance of medication errors resulting
from over- or underdosing
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14. Reduce Medication Errors
Report medication errors
Encourage others to report medication
errors or suspected ADE’s
Participation in quality-improvement
committees
Develop and enforce policies and procedures
for safe medication practices 14
15. Drug Use Evaluation
Low therapeutic index drugs
Those responsible for serious
medication errors
High frequency of preventable adverse
drug reactions
Expensive medications
Education
Patients
Nursing unit staff
Physicians
Pharmacy students and residents
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16. Research
Pediatric patients are “therapeutic
orphans”
Insufficient research in pediatric
patients
Expansion of adult diseases into the
pediatric population (i.e. AIDS)
Use of therapeutic agents in children
without FDA approval
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18. Absorption
– Gastrointestinal
pH- gastric acid output maturity is related to
postnatal age and
approaches adult values by 3 months of age
GI motility- neonates have a delay in gastric
emptying time, adult values are reached at 6-8
months of age
GI contents- develops rapidly within the first
year of life,
underdeveloped flora can increase absorption of
drugs (digoxin)
–
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19. 19
Percutaneous
Absorption is increased in the newborn
due to immature
epidermal barrier and increased skin
hydration during the first 2
weeks of life
Increased surface area to weight ratio
increases percutaneous
absorption
20. Distribution
–Body Water
• Neonates are 80% body water compared to 55%
in adults
• Vd is increased for drugs that distribute to
aqueous parts of the body (aminoglycosides)
• Total body fat is 1% in a 29 wk neonate
• Total body fat is 15% in a full term baby
• Total body fat is 20-25% in 2yo toddler
• Fat content tends to increase between 5-10 years
followed by a decrease through age 17
• Vd is increased for drugs that are highly lipid
soluble
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21. – Plasma Protein Binding
• Neonates have decreased plasma protein which
increases unbound concentrations (ex: Phenytoin
may only be 70% bound in a neonate compared to
90% in an adult)
– Blood Brain Barrier
• An immature BBB due to incomplete CNS
myelination results in increased CNS drug
penetration
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22. Metabolism
– Neonates have decreased activity of many enzyme
pathways, that is why drug dosages are decreased
for neonates
P450 activity is 50% of adult levels
Decreased hydroxylation activity leads to
decreased metabolism of phenobarbital, phenytoin,
lidocaine
Children have increased hepatic enzyme activity
between 2-4 years of age. This may be due to large
liver size compared to total body weight. Doses are
increased during this time for theophylline,
phenytoin, and phenobarbital.
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23. At birth, kidney function is decreased, GFR
matures first, then tubular secretion, and lastly
tubular reabsorption
GFR at birth is 2-4 ml/min, which is 0.5% of an
adult level
After the first week of life, a significant
increase in GFR is seen, this explains why
recommended doses change after 7 days of life
At 1 year, GFR reaches 70 ml/min/m2
Around 12-24 month of age, GFR and tubular
secretion are more mature than tubular
reabsorption and cause an increased renal
clearance of drugs (digoxin)
Excretion
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25. • Safe pediatric dosages calculated by:
– Body weight
• Measured in mg per kg, mcg per kg, etc.
– Body surface area (BSA)
• Measured in m2
Remember
1 kg = 2.2 lb
– When converting pounds to kilograms, round kilogram
weight to one decimal place
• Tenths
1 lb = 16 oz
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26. Dosage is optimally calculated by using the
child’s body weight or mass and the appropriate
dose in milligrams per kilogram (mg/kg).
A. Fried’s rule for infants
age (in months) X adult dose
............................
= dose for infant
150
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27. age (in years)
............................. X adult dose =
age (in years) + 12
dose for child
Young’s rule for children 2 years old or older
weight (lb) X adult dose
........................................ = dose for child
150 lb (avg wt of adult)
Clark’s rule
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28. BSA of child (m)2 X adult dose
............................................... =
1.73 m2 (avg adult BSA)
approximate dose for
child
Child’s dosage based on body surface area
(BSA)
In the case of some drugs, such as chemotherapy, doses are
based on body surface area (BSA). This value can be determined
from the patient’s height and
weight, using either a nomogram or the following equation:
height (cm) X weight (kg)
BSA (m)2 = .......................................
3600
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29. Although the total body water content of
an adult
accounts for approximately 60% of body
weight, the total body water content of a
healthy newborn is
(A) 40%.
(B) 50%.
(C) 70%.
(D) 80%.
(E) 90%.
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