geriatric and pediatric pharm

Question 1

define age ranges for premature, neonatal, infants, children, adolescents, geriatric

Answer 1

Premature: born before 37 weeks gestational age. Neonatal: 1 day-1 month. Infants: 1 month-1 year. Pediatric - children 1-11 years. Adolescent: 12-16 years. Geriatric: > 65 years

Question 2

pediatric absorption

Answer 2

By 1 year of age, adult-child differences NOT substantial

Question 3

pediatric volume of distribution

Answer 3

Body proportions and fat distribution change with age, but effect on Vd for most drugs is relatively minor. Loading doses change little

Question 4

pediatric hepatic metabolism- list phase 1 pathways and when they reach adult levels

Answer 4

CYP1A2: 4-5 months. CYP2C9: teens (<30% at birth). CYP2D6: 10 years (no activity at birth). CYP3A4: 1 year (30-75% at birth).

Question 5

List substrates for CYP1A2, CYP2C9, CYP2D6 and CYP3A4

Answer 5

CYP1A2: caffeine, theophylline. CYP2C9: NSAIDS, Warfarin. CYP2D6: antidepressants, opioid analgesics. CYP3A4: statins, calcium channel blockers

Question 6

pediatric hepatic metabolism- list phase 2 pathways and when they reach adult levels

Answer 6

1. sulfate and glycine conjugation- at birth. 2. acetylation- 2 yrs. 3. glucuronide conjugation- 2-3 yrs (0-25% at birth). This is the cause of grey baby syndrome with chloramphenicol

Question 7

pediatric renal function maturation

Answer 7

Adult level functioning is achieved by 5 months for renal blood flow, 6 months for tubular sec and 3 years for GFR

Question 8

compare renal vs hepatic clearance of drugs in children

Answer 8

renal clearance is more predictable and renally excreted drugs are cleared more rapidly. Hepatic elimination varies widely in children

Question 9

pediatric maintenancedoses

Answer 9

Drugs are cleared more rapidly in children (in general), whether eliminated via renal or hepatic processes. Maintenance doses (calculated on a mg/kg/day basis) are often higher than encountered in adults

Question 10

pediatric therapeutic levels of drugs (Cp)

Answer 10

Therapeutic levels of drugs (Cp) in children same as adults. Calculated based on weight

Question 11

drugs that affect growth in kids

Answer 11

Most psychoactive agents have modest effects on growth. Anti-inflammatory corticosteroids (including topical agents) are potent inhibitors of growth

Question 12

drugs that affect intellectual development in kids

Answer 12

barbiturates

Question 13

side effects of tetracyclines in kids

Answer 13

are incorporated into growing bone and teeth and are contraindicated in children and in pregnancy

Question 14

Aspirin side effects in kids

Answer 14

not recommended for use in children prior to puberty because of risk for hepatic dysfunction: Reyes syndrome- fatty liver with acute encephalopathy. Aspirin interaction with chicken pox and influenza

Question 15

List drugs that have potential for life threatening sx in young children

Answer 15

Benzonatate, iron, antidepressants, antipsychotics, antimalarials, antiarrythmics, Ca channel blockers, sulfonylurea hypoglycemics, opioids, acetaminophen, diphenhydramine

Question 16

geriatric changes in absorption

Answer 16

Rate of absorption changes slightly but extent of absorption (bioavailability) is unchanged. increased gastric pH, decreased absorptive surface, splanchnc blood flow, GI motility and gastric emptying rate

Question 17

geriatric changes in distribution

Answer 17

decreased cardiac output, hepatic/ renal blood flow, body fat (changes volume of distribution), total body water, relative tissue perfusion and albumin

Question 18

geriatric changes in metabolism

Answer 18

decreased liver mass, hepatic blood flow and enzyme activity (changes clearance rate)

Question 19

geriatric changes in excretion

Answer 19

decreased renal blood flow, decreased GFR (changes clearance), tubular secretion and renal mass

Question 20

how does decreased gastric acid affect drug absorption in geriatrics

Answer 20

1. Decrease in absorption of weak acid drugs (e.g., warfarin, penicillin). 2. Increase in absorption of weak base drugs (e.g., TCADs, benzodiazepines, opioid analgesics, anticonvulsants). 3. Inappropriate (early) release of enteric-coated drugs (e.g., aspirin)

Question 21

List disease which may affect absorption

Answer 21

CHF: slowed or reduced absorption. Gastroparesis: decreased gastric emptying and GI motility

Question 22

list drugs/ drug properties which may affect absorption

Answer 22

1. drugs that decrease gastric emptying/ motility- anticholinergics like diphenhydramine and TCADs. 2. drugs that increase gastric emptying/ motility- metoclopramide, cisapride, stimulant laxatives. 3. drugs that decrease absorption by interacting in the guy- ie. cholestyramine binds warfarin

Question 23

drugs which have a decreased Vd in geriatrics

Answer 23

Water soluble drugs will have decreased Vd due to decreased total body water. This increases plasma concentrations of these drugs. Ie. digoxin, aminoglycosides, lithium. This may lower the loading dose

Question 24

drugs which have an increased Vd in geriatrics

Answer 24

lipid soluble drugs have increased Vd due to increased body fat. This causes slower elimination, increased half life and drug accumulation. Ie. Chlordiazepoxide and diazepam. May require lower maintenance dose

Question 25

How do geriatric serum albumin levels affect distribution

Answer 25

decreased albumin Can result in increase in free (active) drug concentrations of highly protein bound drugs like phenytoin, phenobarbital, warfarin and diazepam.

Question 26

describe drug metabolism in general

Answer 26

lipophilic drug undergoes phase 1 enzyme action (CYP450) to form hydrophilic less active compound. This then undergoes phase II glucuronidation or conjugation to form highly water soluble, inactive substrate

Question 27

how do phase I and phase II reactions change in geriatrics

Answer 27

Phase I reactions (oxidation, reduction, hydrolysis) decrease with age in 30-35% of elderly patients. Drugs like chlordiazepoxide and diazepam will have an increased plasma half life. Phase II reactions (conjugation, glucuronidation) are minimally affected by aging. This includes lorazepam, oxazepam, temazepam

Question 28

Which benzodiazepams are preferred in elderly

Answer 28

Lorazepam / oxazepam are preferred over diazepam / chlordiazepoxide due to their phase II metabolism

Question 29

Dosing of renally excreted drugs in geriatrics

Answer 29

Drugs eliminated primarily by the kidneys will accumulate in the presence of renal impairment. Use renal dosing based on creatinine clearance

Question 30

equation for creatinine clearance

Answer 30

[(140-age) x (Kg) x 0.85 (females)] / (serum creatinine x 72)

Question 31

Beers criteria

Answer 31

Addresses inappropriate drugs regardless of diagnosis- conditions OR drug use in certain diagnosis-condition for elderly patients.

Question 32

Worst drugs from the Beers criteria

Answer 32

amitriptyline, diazepam, doxepin

Question 33

Beers criteria- drugs to avoid in HTN

Answer 33

pseudoephedrine, methylphenidate

Question 34

Beers criteria- drugs to avoid syncope or falls

Answer 34

benzos, TCADs

Question 35

List drugs that worsen arthralgias, myopathies and osteoporosis

Answer 35

Worsened by corticosteroids, phenytoin, heparin-warfarin, decreased vitamin D intake

Question 36

list drugs that worsen movement disorders

Answer 36

Worsened by dopamine receptor blockers: antipsychotic agents, metoclopramide

Question 37

list drugs that worsen tinnitus and vertigo

Answer 37

Worsened by aspirin, aminoglycosides, ethacrynic acid

Question 38

list drugs that worsen hypotension

Answer 38

Worsened by beta-blockers, calcium channel blockers, diuretics, vasodilators, antidepressants

Question 39

list drugs that worsen psychomotor retardation

Answer 39

Worsened by benzodiazepines, antihistamines, antipsychotic agents, antidepressants

Question 40

receptors involved in urination

Answer 40

GO: stimulate Muscarinic receptors (bladder and neck), block alpha 1 receptors (trigone). Stop: block M or stimulate alpha1, Beta2 or 3 (bladder)

Question 41

list drugs that worsen urinary retention and overflow

Answer 41

Worsened by anticholinergic agents, agents with anticholinergic side effects (tricyclic antidepressants, antihistamines, typical antipsychotic agents), smooth muscle relaxants, a -adrenergic agonists. Treated with tamsulosin (flomax), a alpha-adrenergic antagonist

Question 42

List drugs that worsen stress incontinence

Answer 42

a-adrenergic antagonists (prazosin, doxazosin)

Question 43

list drugs that worsen urge incontinence due to detrusor hyperreflexia (overactive bladder)

Answer 43

Worsened by cholinergic drugs for dementia (AChEIs), diuretics. Treated with: antimuscarinic agents [tolterodine]

Question 44

List drugs that worsen constipation

Answer 44

Worsened by opioid analgesics, antimuscarinic agents, 1st gen antihistamines (esp. diphenhydramine), CCBs- verapamil

Question 45

List drugs that cause metabolic alterations leading to mental state dysfunction

Answer 45

Metabolic alterations with beta-blockers, corticosteroids, diuretics, sulfonylureas

Question 46

list drugs that cause cognitive impairment

Answer 46

opioid analgesics, cimetidine, propranolol, antipsychotic agents, anticonvulsants, BDZs

Question 47

list drugs that cause behavioral toxicity

Answer 47

anticholinergics, cimetidine, l-dopa, digoxin, opioid analgesics, β-blockers, corticosteroids