Special Populations

Question 1

Pregnancy: Teratogen

Answer 1

Teratogens are drugs or other agents that can disrupt development of the fetus or halt pregnancy

Question 2

Teratogens and trimesters

Answer 2

First trimester is the period of greatest danger for drug-induced developmental defects such as gross malformations because of enormous cell multiplication and differentiation

Second & Third trimester
Disruption of function (not anatomy) such as brain development

Question 3

Pediatric Considerations: ABSORPTION

Answer 3

Gastric environment less acidic
Gastric emptying slowed
First pass reduced (immature liver)
Topical absorption faster
Intramuscular absorption faster

Question 4

Pediatric Considerations: DISTRIBUTION

Answer 4

Total body water:
70-80% in full-term infant
85% in premature neonate
64% in children 1-12 yrs old

Greater TBW = lower fat content

Protein binding decreased due to decreased protein made in immature liver

Immature blood-brain barrier allows more drugs to cross to brain

Question 5

Pediatric Considerations: METABOLISM

Answer 5

Immature liver does not produce enough microsomal enzymes (CYP enzymes) so metabolism reduced

Question 6

Pediatric Considerations: EXCRETION

Answer 6

Immature kidney affects glomerular filtration rate and tubular secretion

Decreased perfusion rate of kidneys = reduced excretion of drugs

Question 7

Other pediatric considerations

Answer 7

•Skin is thin/permeable
•Stomach lacks acid to kill bacteria
•Lungs lack mucus barriers
•Body temp poorly regulated
•Dehydration occurs easier
•Liver/kidneys immature, impairing drug metabolism and excretion

Question 8

Older adult (geriatric) considerations

Answer 8

Geriatric: >65

Use of meds common (20-40% of all prescription drugs, >40% of OTC drugs)

Polypharmacy: Concurrent multiple meds

More sensitive to drugs compared to young adults (pharmacokinetic changes, health conditions, polypharmacy, drug adherence)

Question 9

Physiological Changes in Geriatric Populations

Answer 9

•Cardiovascular: decreased cardiac output, decreased blood flow to organs = decreased absorption and distribution

•GI: Increased pH causes altered absorption, decreased peristalsis causes delayed gastric emptying

•Liver: Decreased CYP450, thus decreasing metabolism

•Kidney: Reduced function, decreased excretion of water soluble drugs and metabolites