Objectives for this present are to define: terminology explain principles of drug action describe pharmacokinetic functions principles of pharmacodynamics identify adverse drug reactions

1. Pharmacology for
Rehabilitation Nursin
g
Mohammad-sajjad lotfi (PhD student of gerontology)
God is online, be careful…

2. •The information contained in this present is intended to assi
st
rehabilitation nurses in pharmacological management for pa
tients.
•This is not a complete presentation of the:
1-issues of pharmacology in rehabilitation medicine
2- nor is it intended to replace comprehensive pharmacolog
y texts or drug references.
notice

3. •Objectives for this present are to define:
• terminology
• explain principles of drug action
• describe pharmacokinetic functions
• principles of pharmacodynamics
• identify adverse drug reactions
notice

4. PHARMACEUTICS
Pharmaceutics evaluates the physical and chemical principles involve
d in the:
• Design
• Formulation
• Manufacture
• Stability of drug delivery systems
• Application of this knowledge to the bioavailability of medication

5. PHARMACEUTICS
A medication is a chemical that interacts with a living organi
sm to produce a biological response.
Following Characteristics:
1. Medications do not bestow any new function on a tissue
or
organ in the body—they only modify existing functions.
Example: Enzyme inhibition with angiotensin-converting en
zyme (ACE) inhibitors for blood pressure or congestive hear
t failure.

6. PHARMACEUTICS
2. Medications generally exhibit multiple actions rather than
a
single effect. Consequently, medications have incidence of
side effects in addition to therapeutic effects.
* Therefore choosing an agent that is more selective for a
particular receptor could minimize this.
Example: First-generation antihistamines, such as diphenhy
dramine, have more anticholinergic side effects (e.g., dry m
outh, blurred
vision, confusion, and sedation) than the newer antihistamin

7. PHARMACEUTICS
3. Medication Action results from a physiochemical interacti
on
between the drug and an important molecule in the body.
• This molecule could be
1- a receptor or
2- a competence of a membrane structure.

8. PHARMACOKINETICS
•Pharmacokinetics (PK) evaluates the:
1- Absorption
2- Distribution
3- Metabolism
4- Elimination of medication
In essential is what the body does to the medication.

9. PHARMACOKINETICS
•Many variables can affect PK and are discussed througho
ut this
chapter.
• The processes associated with pharmacokinetics include:
1- Absorption 2- Bioavailability
3- Distribution 4- Metabolism
5- Elimination 6- clearance
7- Half-life
* These processes ultimately affect the concentrations avail

10. PHARMACOKINETICS
Absorption
• Medications have 100% absorption when administered
intravenously.
•All other forms of administration depend on the:
1- Physiochemical properties of the drug
2- Dosage form
3- Anatomy and physiology of the absorption site.
* thinner skin and absorption

11. PHARMACOKINETICS
Bioavailability
•Bioavailability measures the rate and extent of therapeutical
ly
active medication that reaches the systemic circulation.
•When the bioavailability is rated less than 1 (or 100%)' this
means that :
• either the dosage form did not release all of the medication
• that some of the medication was eliminate destroyed by aci
d or
other means before it reached the systematic circulation.

12. PHARMACOKINETICS
Bioavailability
•Some medications have very low bioavailability, such as
Aldosterone. Administering these drugs correctly is very imp
ortant.
•Check references for any drug-food interaction, and determi
ne
whether the medications must be taken with food to increase
bioavailability.
• Just as important, some medication must be taken on an e
mpty

13. PHARMACOKINETICS
Bioavailability
• Rehabilitation nurses need to understand the meaning bioe
quivalence when explaining brand-name versus geriatric me
dications.
• A medication is deemed
bioequivalent when the area
under the concentration-time
curve (AUC), maximum serum
or blood
concentrations (Cmax) and tim
e Cmax occur Tmax

14. PHARMACOKINETICS
Bioavailability
• When this occur, the serum concentration versus time curv
es for two dosage forms could be superimposed and therefor
e identical.

15. PHARMACOKINETICS
Bioavailability
•Therapeutic index is the difference between where the
concentration of a drug reaches the therapeutic level and the
level of concentration where the drug becomes toxic.
•Many drug have a wide therapeutic index, but some such a
s way drugs have Coumadin, Depakote, or Dilantin have a n
arrow
therapeutic index, so small changes in the dosage level coul
d cause toxic result.

16. PHARMACOKINETICS
Distribution
•When medication is absorbed, the drug molecules are carri
ed
throughout the body by the systemic circulation, which carrie
s them
to the target site of action (receptor) as well as other tissues
and
organs.
•The passage of a drug molecule across a membrane depen
ds on
the chemical makeup of the drug.

17. PHARMACOKINETICS
Distribution
• Small molecules permeate cells, organs, and tissues quickl
y
• lipophilic medications deposit in fat tissues that release the
medication slowly.
• Medications bound to proteins, such as albumin, may beco
me too
large for easy diffusion.
•The volume of distribution is the amount of drug in the body
compared to the concentration measured in plasma, serum,

18. PHARMACOKINETICS
Metabolism
•Drug metabolism is the process in the body that makes a ch
emical molecule more polar to hinder its reabsorption and fa
cilitate
elimination.
•The four main processes of drug metabolism are grouped in
to
phase I (oxidation, hydrolysis, and reduction)
Phase II (conjugation).

19. PHARMACOKINETICS
Metabolism
•Phase I reactions include the cytochrome P-450 system, wh
ich is an enzyme system in the liver that metabolizes drugs.
•Enzymes involved in the biotransformation are located prim
arily in the liver; however, other tissues, such as the kidney, l
ung, small intestine, and skin also contain enzymes.

20. PHARMACOKINETICS
Metabolism
• New findings about the multiple interactions within these va
rious
enzymes.
• One interaction to highlight is that of grapefruit juice becaus
e it inhibits intestinal cytochrome P-450. As a result, it increa
ses levels of drugs metabolized by intestinal CYP 3A4, such
as alprazolam,
cyclosporine, felodipine, and nifedipine.

21. PHARMACOKINETICS
Elimination
• Elimination is the irreversible removal of drug from the bo
dy by all routes.
• The main organ in this process is the kidney.
• Most commonly, renal function is expressed by the degree
of
creatinine clearance.
• Some drug dosages must therefore be adjusted based on
the
creatinine clearance.

22. PHARMACOKINETICS
Elimination
• It is important to evaluate an individual's renal function to
appropriately evaluate dosages of some medications.
•There are various formulas used to calculate creatinine clea
rance,
but one of the most common is the Cockcroft-Gault.
•This formula is as follows:
• Creatinine clearance =
(140 — Age) x Weight in kg/ (72.x Serum creatinine)
For women, multiply by 0.85

23. PHARMACOKINETICS
Clearance
• The rate at which a drug is eliminated by the body is an
important parameter that can be affected by many variabl
es.
• Physiologically, it is determined by the:
1. Blood flow to the organ that metabolizes (i.e., liver)
2. Blood flow to the organ that metabolizes Eliminates (i.e.,
kidney
3. the efficiency of the organ in extracting the medication fro
m the body.

24. PHARMACOKINETICS
Clearance
• High-clearance medications, such as propranolol, are extensively
metabolized by the liver.
• low-clearance medications, such as warfarin, elimination is equal to th
e
fraction of unbound, "active,“ medication in the blood and the intrinsic
ability of the organ to clear these medications from the body.
• These issues become important when introducing drugs that increase
or
decrease the metabolism of certain substrates or displace binding of h
ighly
protein-bound medications.

25. PHARMACOKINETICS
Half-Life
• The half-life (t,A) is the amount of time it takes the plasma
concentration of a medication to decrease by one half after
completing absorption and distribution.
• This important parameter provides the rehabilitation nurse with
insight into when a medication reaches steady state (approxim
ately 3 to 5 half-lives).
• Many factors affect PK principles and need to be taken into
consideration, including age (e.g., pediatric and geriatric chang
es),
gender, body build, drug-drug, drug-disease, and drug-food

26. PHARMACODYNAMICS
• Pharmacodynamics (PD) is the study of biochemical and
physiological effects of medications and their mechanism
of action.
• Core definitions and concepts aid in understanding thes
e processes is: what the drug does to the body

27. PHARMACODYNAMICS
Core components
Protein target s for drug binding include
1. enzymes (e.g., cyclooxygenase)
2. carrier molecules (e.g. Na/K pump)
3. ion channels (e.g., voltage gated calcium channels)
4. receptors (usually proteins designed by nature to confer a re
sponse or transduce a signal to a naturally occurring ligand).

28. PHARMACODYNAMICS
Core components
• Medication act selectivity on particular tissue or cell, a proces
s
termed drug specificity.
• For example, angiotensin act selectivity on vascular smooth
muscles.
• Most drug do not act with complete specificity. Therefore side
effect
may occur.

29. PHARMACODYNAMICS
Core components
Medication bind to receptor differently as described in the followi
ng:
1- At equilibrium, binding is related to drug concentration.
2- Higher selective drugs need lower concentration to approach
saturation of the receptors and clinically can result in fewer adve
rse
side effects.
3- Competitive antagonism occurs when two or more medication
s
compete for the same receptors, and one may reduce the affinity

30. PHARMACODYNAMICS
Core components
• After binding to the receptor site, the following different response
s can occur:
1. Agonists initiate changes in cell function, producing various effe
cts.
The potency depends on:
1. affinity (tendency to bind to receptors)
2. efficacy (ability once bound to produce an effect)
Full agonists produce maximal effect and have high efficacy;
partial agonists produce only submaximal effect and intermediate ef
ficacy.

31. PHARMACODYNAMICS
Core components
2. Antagonists bind to receptors without initiating changes. Types of ant
agonisms
• Chemical antagonism, such as when a chelating agent binds to a heav
y metal
• Pharmacokinetic antagonism, such as cytochrome P-450 inducers
(carbamazepine, phenobarbital) that increase the metabolism of a subst
rate such as warfarin.
• Noncompetitive antagonism (blocking a receptor-effector linkage), suc
h as
omeprazole (Prilosec), a proton pump inhibitor
• Physiological antagonism, wherein two agents balance each other, su

32. PHARMACODYNAMICS
Receptor Level Changes
• Receptor level changes describe a change in conformational state o
r a loss of receptors, such as what happens with beta-receptors.
• Knowing the basic pharmacodynamic principles assist rehabilitation n
urse in
understanding how long medication require to reach efficacy and what t
o
expect concerning side effects or toxicity.

33. Understanding pharmacological change
across the life span
Geriatric Considerations
All rehabilitation nurses need to heighten their awareness a
bout
medications and the elderly.
Many medications are more likely to produce adverse effec
ts and
lead to negative outcomes in older persons.
A review of the PK different in this population helps with un
derstanding the Presses

34. Understanding pharmacological change
across the life span
Geriatric Considerations
Effect on Absorption
• Changes in absorption are not usually clinically significant.
• However, older person have describe gastric acidity and decreased
gastrointestinal tract flow.
• They also have delayed gastric emptying and a lipid content of their
skin.

35. Understanding pharmacological change
across the life span
Geriatric Considerations
Effects on Distribution
• Changes in distribution in the elderly include the following:
• Decreased total body water, which increases potential dehydration, especially
when
taking diuretics.
• Body fat increases from 15% to 30%, and lean body, weigh, decreases in prop
ortion
to total body weight. The result is in increase in the volume of distribution and
half time of agents such as diazepam (Valium).
• There is a decreased serum albumin level, leading to an increase in concentra
tions of
highly protein-bound drugs phenytoin).

36. Understanding pharmacological change
across the life span
Geriatric Considerations
Effects on Metabolism
• Metabolism is altered in the elderly by the following:
1- There is a decrease in liver mass
2- Phase I oxidative process by cytochrome P-450 appears to be decre
ased.
• No changes have been noted in the phase II coupling of a parent dr
ug or
phase by glucoronidation, sulfation, or acetylation

37. Understanding pharmacological change
across the life span
Geriatric Considerations
Effects on Elimination
1- Elimination of medications is affected by a decrease in the siz
e of
the kidney (20%) accompanied by reduced renal blood flow,
glomerular filtration rate, and tubular excretory capacity.
2- Most medications are metabolized and inactivated to some ex
tent in
the liver, and age-related decreases in liver size, hepatic blood fl
ow
and enzymatic capacity can impair the body's ability to metaboliz

38. Understanding pharmacological change
across the life span
Geriatric Considerations
Effects on Elimination
• Likewise, the kidneys are the primary site of drug excretion, an
d
progressive decreases in renal mass, renal blood flow, filtration
capacity and nephron function can reduce the body's ability to r
emove various drugs and their metabolites from the bloodstrea
m.
• Because of these age-related physiological changes, the body i
s not
able to eliminate drugs in a timely and predictable manner, thus

39. ADVERSE DRUG REACTIONS
defines an adverse drug reaction (ADR) as
"any incident in which the use of 'medication (drug or biologic) at any d
ose, a medical device, of a special nutritional product (e.g., dietary sup
plement, infant formula, medical food) may have resulted in an adverse
outcome in a patient.“
• It is important to note that ADRs have been reported as the fourth le
ading cause of death in the United States, following heart disease, c
ancer, and
stroke.

40. ADVERSE DRUG REACTIONS
• Patients at high ADS include, but are not limited to, pediatric and ge
riatric
aggregate and person with hepatic or renal failure.
• High-risk medication extend beyond aminoglycoside, digoxin, hepari
n, phenytoin, and warfarin.

41. TREATMENT OF PAIN AND INFLAMMATION
Opioid analgesics
• Opioid (narcotic) medications such as morphine and mep
eridine (Table 12.1) are powerful analgesics that bind to n
euronal
receptors in the spinal cord and brain.
• These medications reduce synaptic activity in pain-trans
mitting
pathways, thereby decreasing pain perception.
• Common side effects of opioids include sedation, respirat
ory
depression, constipation and postural hypotension.

42. TREATMENT OF PAIN AND INFLAMMATION
Opioid analgesics
• Elderly reactions to opioid such as confusion, anxiety, ha
llucinations and euphoria/dysphoria.
• Opioids can also increase the risk of falls in older adults,
by
either increasing sedation or causing dizziness from orth
ostatic hypotension.
• These reactions are especially common in elderly patien
ts
recovering from surgery, perhaps because of opioid side
effects being magnified by the residual effects of the gen
eral anesthetic and because of the disorientation and wo

43. TREATMENT OF PAIN AND INFLAMMATION
Non-opioid analgesics
• Nonsteroidal anti-inflammatory drugs (NSAIDs) are th
e
primary group of non-opioid analgesics.
NSAIDs include aspirin, ibuprofen and similar agents
(see Table 12.1) and these drugs are often effective in
treating
mild to moderate pain.
• These medications actually produce four clinically imp
ortant effects: decreased pain, decreased inflammatio
n, decreased fever and decreased blood coagulation.

44. TREATMENT OF PAIN AND INFLAMMATION
Non-opioid analgesics
• There is also considerable evidence that NSAIDs may d
ecrease the risk of certain cancers, including colorectal c
ancer.
• All of these effects are mediated through inhibition of the
biosynthesis of lipid compounds called prostaglandins.
• Certain prostaglandins mediate painful sensations by
increasing the nociceptive effects of bradykinin

45. TREATMENT OF PAIN AND INFLAMMATION
Non-opioid analgesics
• NSAID-mediated inhibition of prostaglandin synthesis theref
ore
helps reduce painful sensations in a variety of clinical conditi
ons.
• The primary problem associated with NSAIDs is gastrointest
inal
distress, including gastric irritation and ulceration.
• These medications may also cause damage to the liver and
kidneys, especially in older adults who have preexisting hep
atic or renal
dysfunction.

46. TREATMENT OF PAIN AND INFLAMMATION
Non-opioid analgesics
• In addition to traditional NSAIDs, newer drugs known as
COX-2
inhibitors have been developed.
• These drugs are so named because they inhibit the cyclo
oxygenase (COX)-2 enzyme that synthesizes prostagland
ins during
pathological conditions.
• The COX-2 enzyme synthesizes prostaglandins that caus
e pain,
inflammation and other harmful effects, whereas the COX
-1

47. TREATMENT OF PAIN AND INFLAMMATION
Non-opioid analgesics
• Traditional NSAIDs (aspirin, ibuprofen) inhibit both
isoforms of the COX enzyme, the COX-2 drugs are design
ed to
inhibit only the production of harmful prostaglandins (reduc
ing
pain and inflammation) while sparing the production of
beneficial prostaglandins in the stomach, kidneys, and oth
er
organs and tissues.
• Indeed, the incidence of gastric problems is lower with CO
X-2
drugs, and some older adults have used these drugs succ

48. TREATMENT OF PAIN AND INFLAMMATION
Non-opioid analgesics
The COX-2 drugs, however, may also produce serious cardio
vascular problems including heart attack and stroke in suscep
tible patients.
Hence, these drugs should be avoided in those at risk for
cardiovascular disease.
Currently, celecoxib (Celebrex) is the only COX-2 drug that re
mains on the market, and future studies will be needed to det
ermine if this drug and newer COX-2 inhibitors can be used s
afely in older adults who have an acceptable risk profile.

49. TREATMENT OF PAIN AND INFLAMMATION
Non-opioid analgesics
• Acetaminophen (paracetamol), the active ingredient in
Tylenol and other products, is another type of non-opioi
d analgesic.
• This agent is different from the NSAIDs in that it does n
ot
produce any appreciable anti-inflammatory or anticoag
ulant
effects.

50. TREATMENT OF PAIN AND INFLAMMATION
Anti-inflammatory medications
• acetaminophen does not produce gastrointestinal irritati
on, but
this medication can cause severe hepatotoxicity in thos
e with
liver disease or after an overdose.
• Treatment of inflammation consists primarily of the NSA
IDs
and anti-inflammatory steroids.

51. TREATMENT OF PAIN AND INFLAMMATION
Anti-inflammatory medications
• More severe inflammatory conditions often require the us
e of
anti-inflammatory steroids known as glucocorticoids.
• Medications such as prednisolone and cortisone (see Tab
le 12.1) inhibit a number of the cellular and chemical aspe
cts of the
inflammatory response, often producing a dramatic decre
ase in the symptoms of inflammation.

52. TREATMENT OF PAIN AND INFLAMMATION
Anti-inflammatory medications
• However, glucocorticoids cause many severe side effects i
ncluding breakdown of collagenous tissues, hypertension,
glucose intolerance, gastric ulcer, glaucoma and adrenocor
tical suppression.
• Tissue breakdown (catabolism) can cause severe muscle
wasting
and osteoporosis, especially in older people who may alrea
dy be somewhat debilitated

53. TREATMENT OF PAIN AND INFLAMMATION

54. PSYCHOTROPIC MEDICATIONS
Antianxiety drugs
•Treatment of anxiety has traditionally consisted of benzodiaz
epines, including diazepam and similar agents (Table 12.2) .
•These drugs work by increasing the inhibitory effects of
7-aminobutyric acid (GABA), an endogenous neurotransmitte
r, in
areas of the brain that control mood and behavior.
•The primary side effect of benzodiazepine agents is sedation
.
•These drugs may also cause tolerance and physical depend
ence

55. PSYCHOTROPIC MEDICATIONS
Antianxiety drugs
• Benzodiazepines also have extremely long metabolic ha
lf-lives in older adults, which means that it takes a very l
ong time to
metabolize and eliminate these drugs.
• As a result, benzodiazepines can accumulate in older p
atients and reach toxic levels, shown by symptoms of co
nfusion, slurred speech, dyspnea, incoordination and pro
nounced weakness.

56. PSYCHOTROPIC MEDICATIONS
Antianxiety drugs
• newer type of non-benzodiazepine antianxiety medication
has
been developed, which is known as buspirone.
• This agent, chemically classified as an azapirone, increas
es
serotonin activity in the brain, thus decreasing symptoms o
f
anxiety.
• Buspirone has been used increasingly in older adults beca
use this agent does not appear to produce sedation or cau
se tolerance and physical dependence.

57. PSYCHOTROPIC MEDICATIONS
Antianxiety drugs
• However, it may take longer to exert its antianxiety effects,
and may not be as effective in treating severe anxiety com
pared with the benzodiazepines.
• A Finally, certain antidepressants such as paroxetine and
yenlafaxine may reduce anxiety even in people who are no
t
depressed.
• they may provide an effective alternative for older adults w
ho do not respond adequately to more traditional antianxiet
y agents.

58. PSYCHOTROPIC MEDICATIONS
Antidepressants
• Several different types and categories of antidepressant
medication exist (see Table 12.2)
• These drugs all share the common goal of trying to increa
se
activity at synapses in the brain that use amine neurotrans
mitters, including catecholamines (norepinephrine), 5-hyd
roxytryptamine (serotonin) and dopamine.

59. Nurological MEDICATIONS
Antidepressants
• Although the details remain unclear, depression is thought
to be
caused by a defect in the release of, or sensitivity to, these
amine neurotransmitters in specific areas of the brain that
control mood (i.e. the limbic system).
• Most antidepressants are nonselective and cause:
• increased activity at synapses that use
norepinephrine, serotonin and dopamine.

60. Nurological MEDICATIONS
Antidepressants
• However, certain antidepressants are more selective for s
erotonin pathways than other amine synapses.
• These drugs, also known as selective serotonin-reuptake i
nhibitors (SSRIs), include fluoxetine (Prozac), sertraline (Z
oloft) and paroxetine (Paxil).
• There is still considerable debate whether SSRIs are more
effective than their nonselective counterparts, but these dr
ugs
may produce a more acceptable side effect profile in older
adults (see below).

61. Nurological MEDICATIONS
Antidepressants
• The primary side effects of traditional (nonselective)
antidepressants are:
sedation
postural hypotension
decreased acetylcholine function (anticholinergic effects), suc
h as dry mouth, urinary retention, constipation, tachycardia an
d confusion
• These side effects are often much more pronounced in old
er
people because of age-related declines in various physiolo
gical systems combined with the fact that some of these dr

62. Nurological MEDICATIONS
Antidepressants
• For example, the elimination half-life of amitriptyline (a traditi
onal nonselective antidepressant) is normally around 16 h in
young
individuals, whereas it may be twice as long (31 h) in health
y older adults.
• More selective agents such as the SSRIstend to have fewer
sedative, hypotensive and anticholinergic effects, and these
drugs may therefore be used preferentially in older adults.

63. PSYCHOTROPIC MEDICATIONS
Antidepressants
• Another primary concern about antidepressants is that the
re is
typically a 1- to 2-week time lag between initiation of drug
treatment and improvement of depression, and some pati
ents
may need up to 6 weeks before receiving the full benefit fr
om
these drugs.
• Depression may actually worsen in some patients during t
his
period, and therapists should be especially careful to note

64. PSYCHOTROPIC MEDICATIONS
Antipsychotics
• Psychosis seems to be caused by increased activity in cert
ain
dopamine pathways of the brain.
• As a result, antipsychotic medications block postsynaptic
receptors in these pathways to help normalize dopaminergi
c
influence.
• These agents typically cause side effects such as sedation,
postural hypotension, anticholinergic effects and movemen
t
disorders including tardive dyskinesia, pseudo-parkinsonis

65. PSYCHOTROPIC MEDICATIONS
Antipsychotics
• Tardive dyskinesia is characterized by oral-facial moveme
nts
such as extending the tongue, grinding the jaw, puffing the
cheeks, and various other fragmented movements of the n
eck, trunk and extremities.
• This problem is often regarded as being the most serious
side
effect of antipsychotic medications because symptoms of t
ardive dyskinesia may take several months to disappear o
r may remain indefinitely after the antipsychotic drug is dis
continued.

66. PSYCHOTROPIC MEDICATIONS
Antipsychotics
• Some of the newer antipsychotics are regarded as 'atypical
'
because they are as effective as traditional agents but pos
e a
lower risk of tardive dyskinesia and other side effects and a
re
better tolerated; hence, these atypical antipsychotics may b
e
used preferentially in older adults.
• Nonetheless, therapists should be cognizant of any aberra
nt

67. PSYCHOTROPICMEDICATIONS

68. Nurological MEDICATIONS
Parkinson's disease
• The motor symptoms of Parkinson's disease (bradykinesia
, rigidity, resting tremor) are related to the loss of dopamin
ergic neurons
in the basal ganglia.
• The primary method of drug treatment is levodopa (i-dopa)
,
which is the metabolic precursor to dopamine.
• Although dopamine will not cross the blood-brain barrier,
levodopa will enter brain tissues where it is subsequently
converted to dopamine, thus helping to restore the influen
ce of

69. Nurological MEDICATIONS
Parkinson's disease
• Levodopa is often administered with carbidopa, a drug that
prevents premature conversion of levodopa to dopamine in
the
peripheral circulation.
• Combining levodopa with carbidopa in preparations such as
Sinemet allows levodopa to reach the brain before undergoi
ng
conversion to dopamine.
• .

70. Nurological MEDICATIONS
Parkinson's disease
• Levodopa is associated with several side effects including
gastrointestinal irritation, hypotension and psychotic-like sy
mptoms.
• Other movement problems, including dyslcinesias and dyst
onias,
may also occur, especially at higher dosages.
• However, the most devastating problems are typically relate
d to
a decrease in long-term effectiveness; patients who respon
d well
to levodopa initially, commonly experience progressively

71. Nurological MEDICATIONS
Parkinson's disease
• This phenomenon is probably related to a progressive incr
ease in the severity of Parkinson's disease; that is, drug th
erapy cannot
adequately resolve the motor symptoms because of the ad
vanced degeneration of dopaminergic neurons in the basal
ganglia.
• Helping patients and their families to deal with the physical
as
well as psychological impact of decreased levodopa effecti
veness is one of the more difficult tasks that therapists face
.

72. Nurological MEDICATIONS
Parkinson's disease
• Several other types of medications are used as supplement
al drug therapy in Parkinson's disease (Table 12.3).
• These agents are typically used to supplement levodopa the
rapy
or they serve as the primary agent when levodopa is poorly
tolerated or no longer effective.
• A common strategy is to combine several agents in low to m
oderate doses to obtain optimal benefits while avoiding the e
xcessive side effects that would occur with large amounts of
any single drug.

73. Nurological MEDICATIONS
Seizures
• Some of the medications commonly used to control seizure
activity are listed in Table 12.3.
• These agents act on the brain to selectively reduce excitabi
lity in neurons that initiate seizures.
• however, it is often difficult to reduce excitation in these ne
urons
without producing some degree of general inhibition throug
hout
the brain.
• This is especially true in the older patient who has had a pr

74. Nurological MEDICATIONS
Seizures
• As a result, older patients taking anti-seizure medications ar
e
especially prone to side effects such as:
• sedation, fatigue, weakness, incoordination, ataxia and visu
al disturbances (e.g. blurred vision and diplopia)
• Therapists should pay particular attention to patients taking
antiseizure medication because they are in a position to help
determine whether dosages are too high (as indicated by ex
cessive side effects) or too low (as evidenced by an increas
e in seizure
activity).

75. Nurological MEDICATIONS
Alzheimer's disease
• Donepezil (Aricept), tacrine (Cognex) and several other
medications (see Table 12.3)
• were developed fairly recently to help improve cognition an
d
intellectual function in patients with Alzheimer's disease.
• These drugs are cholinergic stimulants; they:
1- decrease acetylcholine breakdown at synapses in the brain
2- thereby helping to maintain acetylcholine influence in areas
of the brain that are undergoing the neuronal degeneration ass
ociated with Alzheimer's disease.

76. Nurological MEDICATIONS
Alzheimer's disease
• These drugs do not cure Alzheimer's disease, but prelimina
ry
evidence indicates that they may help patients retain more
intellectual and functional ability during the early stages of t
he
disease.
• The primary side effects associated with these drugs includ
e:
• loss of appetite
• gastrointestinal distress (diarrhea, nausea and vomiting).

77. Nurological MEDICATIONS

78. CARDIOVASCULAR DRUGS
Antihypertensive medications
• Several drug categories (Table 12.4) are used to treat high
blood pressure in older adults and reduce the chance of hy
pertensive
related incidents such as stroke, myocardial infarction and k
idney disease.
• Angiotensin-converting enzyme (ACE) inhibitors prevent the
formation of angiotensin II, which is a powerful vasoconstric
tor and stimulant of vascular smooth muscle growth.

79. CARDIOVASCULAR DRUGS
Antihypertensive medications
• Agents such as: alpha blockers, beta blockers and other
sympatholytic drugs decrease sympathetic nervous system
stimulation of the heart and vasculature, thereby decreasing
myocardial contraction force and peripheral vascular resista
nce.
• Calcium-channel blockers reduce myocardial contractility a
nd
vascular smooth muscle contraction by limiting calcium entr
y into these tissues.
• Diuretics increase sodium and water excretion, thereby dec
reasing blood pressure by reducing fluid volume in the vasc
ular system.

80. CARDIOVASCULAR DRUGS
Antihypertensive medications
• Elderly people with hypertension are treated routinely with di
uretic agents because these drugs are fairly safe and well tol
erated.
• ACE inhibitors have also been used increasingly in older pat
ients
because these agents reduce blood pressure and prevent a
dverse
structural changes in the heart and vasculature.
• sympatholytic and vasodilators tend to produce a
variety of unfavorable side effects in older patients so these
drugs are typically used only in severe cases.

81. CARDIOVASCULAR DRUGS
Antihypertensive medications
• Calcium-channel blockers can also be used to treat hypert
ension
in older adults, but the short-acting forms of these drugs sh
ould be avoided because they may decrease blood pressur
e too rapidly and increase the risk of myocardial infarction i
n certain patients.
• sustained- or continuous-release versions of the calcium-c
hannel
blockers should be used preferentially in older patients with
hypertension.

82. CARDIOVASCULAR DRUGS
Antihypertensive medications
• Antihypertensive drugs produce various side effects, dependi
ng on
the specific agent; however, it is important that therapists are
aware that hypotension and postural hypotension are always
possible
whenever blood pressure is reduced pharmacologically.
• Blood pressure may fall by more than 10-20 mmHg, especiall
y when an older patient sits or stands up suddenly.

83. CARDIOVASCULAR DRUGS
Antihypertensive medications
• Likewise, physical therapy interventions that cause extensiv
e
peripheral vasodilation must be used very cautiously becaus
e these interventions add to the hypotensive drug effects an
d produce
dangerously low blood pressure in older adults.

84. CARDIOVASCULAR DRUGS
Treatment of congestive heart failure
• Congestive heart failure (CHF) occurs commonly in older
adults
and is characterized by a progressive decline in myocardia
l
pumping ability.
• The primary medications used to treat CHF are the digitali
s
glycosides such as digoxin (see Table 12.4).
• These agents increase calcium entry into myocardial tissu
es, thereby increasing contractile force.

85. CARDIOVASCULAR DRUGS
Treatment of congestive heart failure
• Digitalis drugs often produce temporary hemodynamic
improvements that decrease the symptoms of CHF, but th
ese
agents do not alter the progression of the disease or decre
ase
the rather high morbidity and mortality rates associated wit
h heart failure.
• These agents have a small safety margin and can accumu
late
rapidly in the bloodstream causing toxicity in older patients
.

86. CARDIOVASCULAR DRUGS
Treatment of congestive heart failure
• Digitalis toxicity is associated with symptoms such as gast
rointestinal distress, confusion, blurred vision and cardiac
arrhythmias.
• Therapists should be alert for these symptoms because di
gitalis-induced arrhythmias can be quite severe or fatal.
• Because of the problems related to digitalis, other medicati
ons
have been used alone or with digitalis drugs to help treat
patients with CHF.

87. CARDIOVASCULAR DRUGS
Treatment of congestive heart failure
• Diuretics and vasodilators have been used to decrease th
e
workload on the failing heart by reducing fluid volume or
decreasing vascular resistance respectively.
• ACE inhibitors have been recognized as being very benefi
cial in patients with CHF.
• These agents decrease angiotensin II-mediated vasoconst
riction
and vascular hypertrophy so that cardiac workload is redu
ced.

88. CARDIOVASCULAR DRUGS
Treatment of congestive heart failure
• Unlike digitalis drugs, ACE inhibitors appear to improve the
prognosis of patients with heart failure and decrease the
morbidity and mortality associated with CHF.
• ACE inhibitors are tolerated fairly well by older adults and h
ave
relatively minor side effects such as a mild allergic reaction
(skin
rash) or a dry persistent cough.
• As a result, ACE inhibitors continue to gain acceptance as a
primary treatment of CHF in the elderly.

89. CARDIOVASCULAR DRUGS
Treatment of hyperlipidemia
• Several drugs have been introduced to the market to help
improve plasma lipid profile and reduce the adverse effects
of atherosclerosis on the cardiovascular system.
• The primary category of lipid-lowering drugs is the statins (
see Table 12.4).
• Statin drugs inhibit an enzyme known as 3-hydroxy-3-meth
ylglutaryl coenzyme A (HMG-CoA) that is responsible for sy
nthesizing
cholesterol in the body.

90. CARDIOVASCULAR DRUGS
Treatment of hyperlipidemia
• This reduces endogenous:
1. cholesterol biosynthesis
2. facilitates a number of other beneficial effects on plasma l
ipids
3. (reduced low-density lipoproteins, reduced triglycerides).

91. CARDIOVASCULAR DRUGS
Treatment of hyperlipidemia
• A second category of anti-hyperlipidemia agents is the fibric
acids.
• Although the exact mechanism of their action is not known,
fibricacids can:
1. reduce triglyceride levels
2. increase low-density lipoprotein breakdown.
• An eclectic group of other agents (e.g. niacin, probuchol) ar
e also available, and these agents work in various ways to t
reat
hyperlipidemia.

92. CARDIOVASCULAR DRUGS
Treatment of hyperlipidemia
Drugs used to treat hyperlipidemia produce various side
effects including:
1. gastrointestinal disturbances (nausea, cramping, diar
rhea).
2. In rare cases, statins can also produce muscular pai
n, weakness and inflammation.
• his so-called statin-induced myopathy' can be quite se
vere
in some people and even lead to breakdown of skelet
al muscle tissues (rhabdomyolysis).

93. CARDIOVASCULAR DRUGS
Treatment of hyperlipidemia
• Therefore, if muscle pain occurs spontaneously in older a
dults or any individual taking lipid-lowering drugs, clinicia
ns should
refer the patient back to the physician immediately to
determine the source of the pain.
• If statin-induced myopathy is the suspected cause, the dr
ug is
usually discontinued and the patient is allowed several w
eeks to recover from the muscle damage before resumin
g exercise or other vigorous activities.

95. Geriatric Rehabilitation manual
Chapter 12, form pages 63-68
References:
Rehabilitation nursing: Prevention,
intervention, and outcomes.
Chapter 7, form pages 91-96

96. Thanks for your
attention
Any questions?
Qazean Village, Kashan, Iran