Geriatric pharmacology is a specialized field focusing on medication use in elderly individuals It explore challenges like polypharmacy, age-related changes in drug metabolism, and the importance of personalized treatment plans for older patients. 20% of hospitalization for those > 65 are due to the medication they’re taking

1. G E R I A T R I C
PHARMACOLOGY
BY
ABHINAV S ( 2n d Year MBBS)
GMC Thir uvallur,TamilN adu

2. CONTENTS
 Introduction to Geriatric Pharmacology
 Renal Function Changes
 Hepatic Changes
 Drug Dosage Adjustments
 Drug Absorption and Distribution
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3. CONTENTS
 Cardiovascular System in the Elderly
 Specific Considerations for Males
 Adverse Drug Reactions in the Elderly
 Multiple Drug Therapy Challenges
 Polypharmacy
 Conclusion
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4. Introduction
Geriatric pharmacology is a specialized field focusing on
medication use in elderly individuals
It explore challenges like polypharmacy, age-related changes
in drug metabolism, and the importance of personalized
treatment plans for older patients.
20% of hospitalization for those > 65 are due to the
medication they’re taking 4

5. Physiologic Changes of Aging Affecting
Absorption
 Physiologic change
• Decreased gastric acidity
• Decreased gastrointestinal blood flow
• Delayed gastric emptying
• Slowed intestinal transit time
 General clinical effect
• None on passive diffusion or bioavailability for most drugs
• Decreased active transport: Decreased bioavailability for
some drugs
• Decreased first-pass effect: Increased
bioavailability for some drugs
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6. Physiologic Changes of Aging Affecting
Distribution
Decreased Total body water
Decreased Lean body mass
Decreased Serum Albumin
Decreased Alpha 1 Acid glycoprotein
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7. Physiologic Changes of Aging Affecting
Elimination
 Physiologic change
 Decreased GFR
 Decreased renal blood flow
 Decreased renal mass
 General clinical effects
 Increased (t½) of renally eliminated
drugs
 Decreased clearance
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8. Diseases with increased incidence in
elderly
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 Alzheimer's disease
 Parkinsonism
 Stroke
 Vascular dementia
 Visual impairment
specially cataracts
and macular
degeneration
 Atherosclerosis
 Arthritis
 Heart failure
 Fractures
 Cancer
 Diabetes

9. PHARMACOKINETICS

10. Renal Function Changes In Elderly
In the elderly, renal function progressively declines (intact
nephron loss)
At 50 years
G F R is ~
75%
At 75 years
G F R is ~ 50%
So drug
doses have to
be reduced
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11. Hepatic Changes In Elderly
Reduction in hepatic microsomal drug metabolizing activity
Altered liver blood flow and its implications
There is also a
reduction in the
hepatic
microsomal drug
metabolizing
activity and liver
blood flow
Oral bioavailability
of drugs with high
hepatic extraction
is generally
increased
But the overall
effects on drug
metabolism are not
uniform
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12. NOTE
Due to lower renal as well as metabolic
clearance, the elderly are prone to develop
cumulative toxicity while receiving
prolonged medication
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13. Drug Dosage Adjustments
Dosage adj ustme nts in the
e ld e r ly-
Stre ptomyc in dosage
changes with age
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14. Let’s see
an example
Dai l y d os e of s tr ep tom ycin i s
0 .75 g af ter 50 year s an d
0 .5 g af ter 70 year s of ag e com p ar ed to 1g f or youn g
ad ul ts .
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15. PHARMACODYNAMICS

16. Pharmacodynamic changes in elderly
 Pharmac odynamic c hange s in the e lde rly have be e n le ss e x te nsive ly
studie d
 Ev ide nc e of e nhanc e d e nd -organ re sponsive ne ss or "se nsitiv ity " to
medications with aging
 Enhanced "sensitivity" may be
due
• Changes in receptor affinity
• Changes in receptor number
• Post-receptor alteration
• Age-related impairment of
homeostatic mechanisms Example:
decreased baroreceptor reflexes
 Age-related changes:
• Increased
• sensitivity to sedation and
psychomotor impairment with
benzodiazepines
• level and duration of pain relief with
narcotic agents
• drowsiness with alcohol
• sensitivity to anti-cholinergic agents
• cardiac sensitivity to digoxin
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17. Drug Absorption and Distribution
 Slower absorption due to reduced gut
motility as well as blood flow to intestines
 Lesser plasma protein binding due to lower
plasma albumin
 Increased or decreased volume of
distribution of lipophilic and hydrophilic
drugs respectively.
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18. Cardiovascular System in the Elderly
A ge d are re lative ly intole rant
to digitalis.
The responsiveness of
adre ne rgic re c e ptor s to both
agonists and antagonists is
re duc e d in the e lde rly and
se nsitiv ity to othe r drugs also
may be alte re d
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19. Cardiovascular drugs
 Antihypertensive drugs
Systolic blood pressure increases with age in
western countries and in most culture in
which salt intake is high
 Drugs used for it are Thiazides , calcium
channel blocker, beta blockers etc
ADRS related to these drug
Dizziness and falls
Orthostatic hypotension 19

20. Specific Considerations for Males
Due to prostatism in elderly
males, even mild
anticholinergic activity of the
drug can accentuate bladder
voiding difficulty
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21. Adverse Drug Reactions in the Elderly
Elderly are also likely to be on multiple drug therapy for
hypertension, ischaemic heart disease, diabetes, arthritis
etc.
This increases many fold the chances or drug
interactions.
They are more prone to develop postural instability,
giddiness and mental confusion.
In general, the incidence of adverse drug reactions is
much higher in the elderly
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22. Multiple Drug Therapy Challenges
Common conditions in the elderly that often
lead to polypharmacy include
Hypertension
Diabetes
Osteoarthritis
Cardiovascular diseases
Mental health disorders
Managing these conditions often requires
multiple medications
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23. Polypharmacy
Polypharmacy refers to the simultaneous use
of multiple medications by a single
individual.
It can pose risks such as drug interactions,
side effects, and increased complexity in
managing health.
Regular review by healthcare professionals is
crucial to optimize medication regimens and
minimize potential harm.
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24. Preventing Polypharmacy
Review medications regularly and
each time a new medication started or
dose is changed
Maintain accurate medication records
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25. CONCLUSION
 Re nal De c line : Elde rly 's kidne y func tion drops,
GF R goe s from 75% at 50 ye ar s to 50% at 75
ye ar s.
 Dose Adj ustments : Drug doses must be reduced
with age
 A lte re d Handling: A ging affe c ts drug
absorption, prote in binding, and distribution,
le ading to pote ntial tox ic ity.
 Adver se Reactions: Elderly face higher risk of
adve r se drug re ac tions due to re duc e d re c e ptor
re sponsive ne ss, pote ntial antic holine rgic
e ffe c ts, and inc re ase d me dic ation inte rac tions.
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26. BIBLIOGRAPHY
Basic and Clinical
Pharmacology by Bertram G.
Katzung Susan B. Master
ESSENTIALS OF MEDICAL
PHARMACOLOGY K D
TRIPATHI
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