special populations pediatric geriatric.ppt

special population of pregency

2. Vulnerable Populations …
Are groups of patients with a high risk for
adverse drug effects
Require careful dosing and/or medication
selection

3. At-Risk Groups Include
Men and women of reproductive age
Pregnant or breastfeeding women
Children and infants
Elderly patients
People with renal or hepatic disease
Obese or underweight patients

4. Reproductive Age
In women: Drugs can affect fertility or damage
ova
In men: Drugs can alter sperm quality and alter sperm quality and
quantityquantity

5. Pregnancy
Pregnancy Categories: A, B, C, D, X
A: Studies in pregnant women have not shown a
risk to the fetus
B: Animal studies have not shown harm to fetus
or animal studies have shown fetal harm, but
studies in pregnant women did not show risk

6. Pregnancy (Cont’d)
Pregnancy Categories (Cont’d)
C: Animal studies show an adverse effect and
there are no adequate studies in pregnant
women or no animal studies have been
conducted and there are no adequate studies in
pregnant women
Many drugs fall into Category C!

7. Pregnancy (Cont’d)
Pregnancy Categories (Cont’d)
D: Studies in pregnant women have shown a risk
to the fetus; benefits may outweigh potential
risks
X: Studies in animals and pregnant women have
shown evidence of fetal harm; the drug is
contraindicated in women who are or may
become pregnant

8. Pregnant Women
First TrimesterFirst Trimester
A woman is least likely to know she is
pregnant
Teratogenic drugs may lead to fetal
malformation or miscarriage

9. Pregnant Women (Cont’d)
Third TrimesterThird Trimester
Drugs may not be safely metabolized and
excreted by the fetus
After DeliveryAfter Delivery
Infants no longer have the placenta to help with
drug excretion, and drugs given before delivery
may cause toxicity

10. Pregnant Women (Cont’d)
For pregnant women who require medication, both For pregnant women who require medication, both
mother and fetusmother and fetus must be consideredmust be considered
Weigh risks and benefitsWeigh risks and benefits
Rule of thumb:Rule of thumb:
LOWEST EFFECTIVE DOSELOWEST EFFECTIVE DOSE
for thefor the
SHORTEST PERIOD OF TIMESHORTEST PERIOD OF TIME

11. Lactation
Many drugs are known or thought to be
excreted in breast milk
Dose in breast milk will be low, but still may
cause adverse effects in the infant
Some drugs interfere with milk supply
American Association of Pediatrics (AAP) lists
drugs usually compatible with breastfeeding
http://aappolicy.aappublications.org/cgi/
content/ full/pediatrics;108/3/776

12. Lactation (Cont’d)
AAP encourages breastfeeding if drug is
unlikely to cause harm
In poorer nations, bottle feeding may not be
an alternative
Research medication at LactMed
http://toxnet.nlm.nih.gov/cgi-bin/sis/
htmlgen?LACT

13. Pediatrics
Most drugs given to children <18 years have
not been approved by the FDA for children
Must contain information for SAFE SAFE
PEDIATRIC USEPEDIATRIC USE

14. Pediatrics: Neonates and Preemies
Difficulty in dosing is secondary to
Immature function of body systems
Rapid weight changes
Progressive maturation of hepatic and
renal function

15. Pediatric Dosing
Doses for children are not automatically less
than those for adults
Higher metabolic rate in children causes
drugs to be processed more quickly
Higher doses are needed to maintain
therapeutic blood levels

16. Pediatric Dosing (Cont’d)
Medication doses are based on body weight Medication doses are based on body weight
or body surface area (BSA)or body surface area (BSA)
Body weight doses expressed as mg/kgmg/kg
BSA doses expressed as mg/mmg/m
22

17. Geriatrics
Adults over Adults over 55 55 have have
↑

↑
risk for toxic reactionsrisk for toxic reactions
Age-related changes affectAge-related changes affect pharmacokinetics
Absorption
Distribution
Metabolism
Excretion

18. Geriatrics (Cont’d)
Changes that affect pharmacokineticsChanges that affect pharmacokinetics

↑ Percentage of body fat
↓ Lean muscle mass
↓ Total body water

↓
Protein

19. Geriatrics (Cont’d)
↓ GI motility and blood flow delays
absorption and distribution
↓ Hepatic and renal function delays
metabolism and excretion
Leads to greater incidence of toxicity
Prescribe lowest possible dose at initiation
of drug(s)

20. Geriatrics (Cont’d)
Monitor for
Signs and symptoms of toxicity and side toxicity and side
effectseffects

Drug interactionsDrug interactions
Usage and complications of OTCs and OTCs and
herbal drugsherbal drugs
Effectiveness

21. Patients with Renal Disease
Kidneys are the mKidneys are the major organ of drug elimination
Failure to account for decreased renal function Failure to account for decreased renal function
is ais a preventablepreventable source of adverse drug reactionssource of adverse drug reactions
AssessAssess
Creatinine clearance
BUN and creatinine
Medication blood levels

22. Patients with Liver Disease
The liver is the mThe liver is the major organ of metabolism
The liver changes drugs from fat soluble to water The liver changes drugs from fat soluble to water
soluble so that kidneys can excrete themsoluble so that kidneys can excrete them
Liver damage leads to higher levels of active Liver damage leads to higher levels of active
drug and more toxicitydrug and more toxicity

23. Patients with Liver Disease (Cont’d)
MonitorMonitor
Liver enzymes
Albumin, total protein
Assess patient forAssess patient for
Enlarged liver
Ascites, jaundice

24. Obese Patients
Drug dosing often based on body weight
Some drugs do not penetrate fatty tissues

To prevent toxicityTo prevent toxicity when giving drugs that do not
penetrate fatty tissue (e.g., digoxin) determine
dose by ideal body weight or estimated lean
body mass
Patients with Extremes of Body SizePatients with Extremes of Body Size

25. Underweight Patients
Patients likely to be underweight

Chronic alcoholics

Patients with AIDS
Patients terminally ill with cancer and other debilitating
illnesses

Amputations
No standard formula for calculating dose in
underweight patients — watch for toxicity
Patients with Extremes of Body Size Patients with Extremes of Body Size
(Cont’d)(Cont’d)