Psychopharmacology

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Psychiatric nursing
Psychopharmacology
Objectives
• Describe the indications, actions, contraindications,
precautions, side effects and nursing implications for the
following classifications of drugs:
 Antianxiety agents
 Antidepressants
 Mood stabilizers
 Antipsychotics
 Antiparkinsonian agents
 Sedative-hypnotics
 Agents for attention deficit and hyperactivity disorders
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Neurological causes of mental
illness
• 1- genetic/heredity
• 2- Stress and the Immune System/
(Psychoimmunology)
• 3- Infection as a Possible Cause
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Why only these classifications of
drugs?
• These are used in the treatment of more than
95% of the psychiatric cases.
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Introduction and history of psychiatric
treatment
•Early 20th century somatic (body) therapies in psychiatry was
established (e.g. insulin shock therapy (ICT), hydrotherapy (wet
sheet packs and ice baths), psychosurgery (trepanation) and
Electroconvulsive Therapy (ECT)).
Introduction and history of psychiatric
treatment
• Before 1950, sedatives & amphetamines (increase
wakefulness and focus and decrease fatigue) were the only
significant psychotropic medications, even these had limited
use because of their toxicity and addicting effect.
• Since 1950s, development of psychopharmacology has
expanded to include antipsychotic, antidepressant, &
antianxiety medications.
• These medications alone are not intended to cure the mental
illness but they minimize the physical and emotional
symptoms.
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• Prior to the 1950s, the focus was on behavioral
interventions and sedatives. The first antipsychotic
medication, chlorpromazine (Thorazine), was
introduced in the mid-50s. Many advances have
occurred since then that allow for the treatment of
people with serious mental illness in the community.
• Medications allow for the correction of imbalances
of brain chemicals.
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Antipsychotic medications
• Antipsychotic medications are beneficial in disorders that
include psychotic states. Examples of such disorders are
schizophrenia, mood disorders with psychotic features, and
dementia with psychotic features.
• The major positive effect of antipsychotics is on decreasing
the symptoms of delusional thinking, hallucinations,
confusion, motor agitation, and motor retardation.
• Antipsychotic medications also decrease formal thought
disorder, blunted affect, bizarre behavior, social withdrawal,
belligerence, and uncooperativeness.
• Antipsychotic drugs work by blocking receptors of the
neurotransmitter dopamine
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Side effect
• The negative effects are primarily the side
effects that may include effects on the
autonomic nervous system,
• Extrapyramidal symptoms (EPS), serious
neurologic symptoms, include
• 1- acute dystonia, includes acute muscular
rigidity and cramping, a stiff or thick tongue
with difficulty swallowing, and, in severe
cases, laryngospasm and respiratory
difficulties.
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Side effect ‘
• 2- pseudoparkinsonism, Drug-induced
parkinsonism: include a stiff, stooped posture;
mask-like facies; decreased arm swing; a
shuffling, festinating gait (with small steps);
cogwheel rigidity (ratchet-like movements of
joints); drooling; tremor; bradycardia; and
coarse pill-rolling movements of the thumb
and fingers while at rest
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• 3- akathisia: is reported by the client as an
intense need to move about.
• The client appears restless or anxious and
agitated, often with a rigid posture or gait and
a lack of spontaneous gestures.
• This feeling of internal restlessness and the
inability to sit still or rest often leads clients to
discontinue their antipsychotic medication.
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• Neuroleptic malignant syndrome (NMS) is a
potentially fatal idiosyncratic reaction to an
antipsychotic (or neuroleptic) drug
• Include: rigidity; high fever; autonomic
instability such as unstable blood pressure,
diaphoresis, and pallor; delirium; and elevated
levels of enzymes, particularly creatine
phosphokinase.
• Clients with NMS usually are confused and
often mute; they may fluctuate from agitation
to stupor.
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• Anticholinergic Side Effects. :include
orthostatic hypotension, dry mouth,
constipation, urinary hesitance or retention,
blurred near vision, dry eyes, photophobia,
nasal congestion, and decreased memory.
• These side effects usually decrease within 3 to
4 weeks but do not entirely remit.
• Tardive Dyskinesia. Tardive dyskinesia (TD), a
syndro me of permanent involuntary
movements
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• Other Side Effects. Antipsychotic drugs also
increase blood prolactin levels. Elevated
prolactin may cause breast enlargement and
tenderness in men and women; diminished
libido, erectile and orgasmic dysfunction, and
menstrual irregularities; and increased risk for
breast cancer, and may contribute to weight
gain
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Client Teaching
• the types of side effects that may occur and
encourages clients to report such problems to
the physician instead of discontinuing the
medication.
• methods of managing or avoiding unpleasant
side effects and maintaining the medication
regimen.
• Drinking sugar-free fluids and eating sugarfree hard candy ease dry mouth.
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• The client should avoid calorie-laden
beverages and candy because they promote
dental caries, contribute to weight gain, and
do little to relieve dry mouth.
• Methods to prevent or relieve constipation
include exercising and increasing water and
bulk-forming foods in the diet. Stool softeners
are permissible, but the client should avoid
• laxatives. The use of sunscreen is
recommended because photosensitivity can
cause the client to sunburn easily
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Antianxiety Drugs (Anxiolytics)
• are used to treat anxiety and anxiety
disorders, insomnia, OCD, depression,
posttraumatic stress disorder, and alcohol
withdrawal
• Benzodiazepines have proved to be the most
effective in relieving anxiety, also may be
prescribed for their anticonvulsant and muscle
relaxant effects.
• Buspirone is a nonbenzodiazepine often used
for the relief of anxiety
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Mechanism of Action
• Benzodiazepines mediate the actions of the
amino acid GABA, the major inhibitory
neurotransmitter in the brain.
• Because GABA receptor channels selectively
admit the anion chloride into neurons,
activation of GABA receptors hyperpolarizes
neurons and thus is inhibitory.
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Psychopharmacology: Antianxiety Agents
• Examples by chemical class and generic name (see table, page
157):
 Antihistamines: Atarax, Vistaril
 Benzodiazepines: Alprazolam (Xanax), Diazepam (Valium),
Lorazepam (Ativan)
 Propanediols: Meprobamate (Miltown)
 Azaspirodecanediones: Buspirone (Buspar)
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Side effect
• Anxiolytic medications have the effect of
disinhibition of fear-induced behavior. Their
side effects include their addictive potential
and overdose sequelae. The major classes of
drugs used today are the benzodiazepines and
nonbenzodiazepines
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Client Teaching
• Clients should not drink alcohol while taking
benzodiazepines.
• Clients should be aware of decreased
response time, slower reflexes, and possible
sedative effects of these drugs when
attempting activities such as driving or going
to work
• he or she should never discontinue
benzodiazepines abruptly or without the
supervision of the physician
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Anxiolytic medications
• These work through a process of synaptic
activity involving the neurotransmitter
gamma-aminobutyric acid (GABA) in the brain
and spinal cord. Benzodiazepines potentiate
GABA, producing relaxation. There are two
types of benzodiazepine receptors in the CNS.
Type 1 receptors are located in parts of the
brain responsible for sedation. Type 2
receptors are located in parts of the brain
responsible for cognition, memory, and
psychomotor functioning
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Psychopharmacology: Antianxiety Agents
Anxiolytics affect all levels of CNS depression (from mild
sedation to coma), except BuSpar which does not depress
the CNS but interacts with serotonin, dopamine, & other
neurotransmitter receptors.
Contraindications: hypersensitivity, combination with
other CNS depressants, pregnancy and lactation, narrowangle glaucoma, shock, coma.
Precautions: caution with elderly or debilitated (weak)
clients, hepatic or renal dysfunction (decrease dosage),
history of drug abuse or addiction, depressed or suicidal
patients (because CNS depressants can increase
symptoms).
Psychopharmacology: Antianxiety Agents
Interactions:
 Increased effects of antianxiety with alcohol, barbiturates,
narcotics (opioids), antidepressants, antipsychotic,
neuromuscular blocking agents.
 Decreased effects with smoking and caffeine.
Nursing diagnosis: the following diagnoses need to be
considered for those on antianxiety medications:
 Risk for injury RT seizures; panic anxiety and
effects of medications intoxication or overdose.
 Risk for activity intolerance RT side effects of
sedation & lethargy
 Risk for acute confusion RT action of the
medication on the CNS
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Nursing interventions for common side
effects
• drowsiness, confusion and lethargy. Instruct the client not to
drive or operate dangerous machinery when taking the
medication.
• Tolerance, physical and psychological dependence. Instruct
the client on long-term therapy not to quit taking it abruptly.
Abrupt withdrawal can be life threatening.
• Ability to potentiate the effect of other CNS depressant.
Instruct the patient not to drink alcohol or take other
medications that depress the CNS.
• Possibility of aggravating symptoms in depressed patients.
Assess the client’s mood daily and take precaution of
potential suicide.
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Nursing interventions for common
side effects
• Orthostatic hypotension. Monitor lying and standing blood
pressure and pulse every shift. Instruct the patient to stand up
slowly from lying or sitting position.
• Paradoxical excitement. Patients may develop symptoms
opposite to the medication’s desired effect. Withhold the
drug and notify the physician.
• Dry mouth. Instruct the client to take frequent sips of water.
• Nausea and vomiting. Have the client take the drug with food
or milk.
• Drug dyscrasias. Symptoms of sore throat, fever, malaise,
unusual bleeding should be reported to the physician
immediately.
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Nursing interventions for common
side effects
• Delayed onset (buspirone/buspar only). Ensure that the client
understands that there is a lag time of 10-14 days between
the onset of therapy and the subsiding of anxiety symptoms.
Client should continue to take the medication and this
medication is not p.r.n and has no physical dependence.
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Antidepressant medications
• are primarily used in the treatment of major
depressive illness, anxiety disorders, the
depressed phase of bipolar disorder, and
psychotic depression.
• Off-label uses of antidepressants include the
treatment of chronic pain, migraine
headaches, peripheral and diabetic
neuropathies, sleep apnea, dermatologic
disorders, panic disorder, and eating disorders
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Mechanism of action
• Although the mechanism of action is not completely
understood, antidepressants somehow interact with the two
neurotransmitters, norepinephrine and serotonin, that
regulate mood, arousal, attention, sensory processing, and
appetite.
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Antidepressants are divided into
four groups
• 1. Tricyclic and the related cyclic
antidepressants
• 2. Selective serotonin reuptake inhibitors
(SSRIs)
• 3. MAO inhibitors (MAOIs)
• 4. Other antidepressants such as venlafaxine
desvenlafaxine (Pristiq) (Effexor), bupropion
(Wellbutrin), duloxetine (Cymbalta), trazodone
(Desyrel), and nefazodone (Serzone).
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Side effect
• The cyclic antidepressants block cholinergic
receptors, resulting in anticholinergic effects
such as dry mouth, constipation, urinary
hesitancy or retention, dry nasal passages,
and blurred near vision.
• More severe anticholinergic effects such as
agitation, delirium, and ileus may occur,
particularly in older adults.
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• Other common side effects include orthostatic
hypotension, sedation, weight gain, and
tachycardia.
• Clients may develop tolerance to
anticholinergic effects, but these side effects
are common reasons that clients discontinue
drug therapy.
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Side Effects of
• Monoamine Oxidase Inhibitors Daytime
sedation, insomnia, weight gain, dry mouth,
orthostatic hypotension, and sexual
dysfunction.
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Psychopharmacology: Antidepressants
Examples by chemical class and generic name or trade
name (se
 Tricyclics: Amitriptyline (Elavil), Imipramine (Tofranil)
 Monoamine Oxidase inhibitors: Phenelzine (Nardil)
 Selective serotonin reuptake inhibitors: Sertraline
(Zoloft)
 Heterocyclics: Trazodone (Desyrel)
Contraindications: hypersensitivity, recovery from MI, &
angle-closure glaucoma.
Precaution: caution with elderly or debilitated clients &
hepatic, renal, or cardiac insufficiency, with seizures.
Psychopharmacology: Antidepressants
Interactions: antihypertensive drugs (decrease therapeutic
response to some antihypertensives & amphetamines)
Nursing diagnosis
Risk for suicide RT depressed mood
Risk for injury RT side effects of sedation,
orthostatic HTN
Social isolation RT depressed mood
Constipation RT side effects
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Nursing interventions for common
side effects
• Dry mouth. Strict oral hygiene. Sips of water. Offer the
patients a sugar less candy.
• Sedation.
• Nausea.
• Discontinuation syndrome. Decreased gradually to avoid
withdrawal syndrome.
• Blurred vision (hazy and indistinct of the sight). Offer
reassurance that this subside after few weeks.
• Constipation.
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Nursing interventions for common
side effects
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Urinary retention. Intake/output chart.
Orthostatic hypotension.
Tachycardia and arrhythmias. Monitor B.P, P.R and rhythm.
Photosensitivity. Protective sunscreen and sunglasses when
outdoor.
• Weight gain. Reduce caloric intake.
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• The negative effects of antidepressants include their
potential side effects and interactions. The tricyclic
antidepressants may aggravate symptoms in a
person with, or susceptible to, schizophrenia.
• Oral MAOIs may cause a potentially life-threatening
hypertensive crisis when combined with foods
containing tyramine, sympathomimetic medications,
or the SSRIs. MAOIs require the client to follow a diet
that restricts tyramine.
• The initiation of antidepressants may contribute to
the risk of suicide in children, adolescents, and
adults.
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Pt teaching
• To minimize side effects, clients generally
should take cyclic compounds at night in a
single daily dose when possible.
• If the client forgets a dose of a cyclic
compound, he or she should take it within 3
hours of the missed dose or omit the dose for
that day.
• Clients should exercise caution when driving
or performing activities requiring sharp, alert
reflexes until sedative effects can be
determined.
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Mood stabilizers
• are used to treat bipolar disorder by stabilizing
the client’s mood, preventing or minimizing
the highs and lows that characterize bipolar
illness, and treating acute episodes of mania.
• Lithium is the most established mood
stabilizer; some anticonvulsant drugs,
particularly carbamazepine (Tegretol) and
valproic acid
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• Mood stabilizers: Lithium aids in the reduction
of neurotransmitter release into the synapse
and enhances its return. Lithium and the
anticonvulsants used as mood stabilizers may
affect neurocellular changes that occur over
weeks and months after their initiation
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Side effect
• lithium therapy include mild nausea or
diarrhea, anorexia, fine hand tremor,
polydipsia, polyuria, a metallic taste in the
mouth, and fatigue or lethargy.
• Weight gain and acne are side effects that
occur later in lithium therapy;
• Taking the medication with food may help
with nausea, and the use of propranolol often
improves the fine tremor. Lethargy and weight
gain are difficult to manage or minimize and
frequently lead to noncompliance.
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• Side effects of carbamazepine and valproic
acid include drowsiness, sedation, dry mouth,
and blurred vision
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Client Teaching
• For clients taking lithium and the
anticonvulsants, monitoring blood levels
periodically is important.
• The time of the last dose must be accurate so
that plasma levels can be checked 12 hours
after the last dose has been taken.
• Taking these medications with meals
minimizes nausea.
• The client should not attempt to drive until
dizziness, lethargy, fatigue, or blurred vision
has subsided
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Guidelines for the treatment of
bipolar disorder are:
– A mood stabilizer is used in all phases of
treatment.
– Atypical antipsychotics are preferable to
conventional older antipsychotics if psychosis is
present.
– Mild depression is treated initially with a mood
stabilizer.
– An antidepressant is used in the beginning of
severe depression.
– Rapid cycling is treated from the beginning with a
mood stabilizer alone, preferably divalproex.
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Psychopharmacology: Mood Stabilizing Agents
 Anti manic: Lithium carbonate (Lithane, drug of choice)
 Anticonvulsant: Carbamazepine (Tegretol)
 Calcium channel blocker: Verapamil (Isoptin)
Indications: Bipolar mania
Action: decrease norepinephrine & serotonin levels in
the body resulting in decreased hyperactivity (Symptoms
subside in 1-3 weeks).
Contraindications: hypersensitivity, cardiac or renal
disease, dehydration (competes with ADH) and cardiogenic
shock.
Caution with pregnancy, lactation, children, & elderly.
Interactions: lithium increases neuromuscular blocking
agents (block the neuromuscular transmission); may result
in neurotoxicity or lithium toxicity (especially in chronic
cases).
Mood Stabilizing Agents
Nursing diagnosis
Risk for injury RT manic hyperactivity
Risk for violence: self-directed or other-directed RT
unresolved anger turned inward on the self or
outward on the environment
Risk for injury RT lithium toxicity
Risk for activity intolerance RT side effects of
drowsiness & dizziness
Nursing interventions for common side effects.
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Psychopharmacology: Antipsychotic Agents
• Psychosis: abnormal condition of the mind, in which the
thought and emotion are impaired involving loss of contact
with reality.
• Also called major tranquilizers & neuroleptics.
 Phenothiazines: Chloropromazine (Thorazine), Thioridazine
(Mellaril)
 Butyrophenone: Haloperidol (Haldol)
• Indications: acute and chronic psychosis, particularly when
accompanied by increased psychomotor activity, treatment of
intractable hiccoughs, control of tics & vocal utterances.
Action: block postsynaptic dopamine receptors in basal
ganglia, hypothalamus, limbic system, brainstem, & medulla.
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Psychopharmacology: Antipsychotic Agents
Contraindications: hypersensitivity, pregnancy & lactation,
diabetic or respiratory insufficiency.
Interactions: antacids & antidiarrheals may decrease
absorption of antipsychotic; barbiturates may increase
metabolism & decrease effectiveness of antipsychotic.
Nursing diagnosis
Risk for other-directed violence RT panic anxiety &
mistrust of others
Risk for injury RT side effects of sedation
Risk for activity intolerance RT side effects of
sedation
Noncompliance with medication regimen RT
suspiciousness & mistrust of others
• Nursing interventions for common side effects.
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Psychopharmacology: Antiparkinsonian Agents
• Examples
 Anticholinergics: procyclidine (Kemadrin), Trihexyphenidyl
(Artane), Biperiden (Akineton)
 Antihistamines: Diphenhydramine (Benadryl)
• Indications: agents are indicated for the treatment of all
parkinsonism (relief symptoms of Parkinson's disease) and
for relief of drug-induced extrapyramidal reactions
(movement disorders such as akinesia and akathesia).
• Action: restore the balance of acetylcholine and dopamine
(increase dopamine or reducing acetylcholine activity in the
CNS). Deficiency in dopamine resulting in excessive
cholinergic activity (neurotransmitters of the
parasympathetic nervous system).
Contraindications: hypersensitivity, duodenal obstruction,
peptic ulcer and myasthenia gravis. Caution with tachycardia,
cardiac arrhythmias, HTN, & hypotension.
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Antiparkinsonian Agents
Nursing diagnosis:
Risk for injury RT symptoms of Parkinson's disease
Hyperthermia RT anticholinergic effect of
decreased sweating
Activity intolerance RT side effects of the
medication
Knowledge deficit RT medication regimen
• Nursing interventions for common side effects.
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Psychopharmacology: Sedative-Hypnotics
• Examples: Barbiturates: Phenobarbital (Luminal)
Secobarbital (Seconal)
• Indications: various anxiety states, insomnia, anticonvulsant and
preoperative sedation.
Action: they cause generalized CNS depression. They may produce
dependence and tolerance.
Contraindications: hypersensitivity, hepatic dysfunction, or severe
renal impairment. Should be short-term only.
Nursing diagnosis:
Risk for injury r/t abrupt withdrawal from long-term use
Sleep pattern disturbance r/t physical condition
Risk for activity intolerance r/t side effects
Risk for acute confusion r/t action on CNS
• Nursing interventions for common side effects.
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Stimulants
• pronounced effects of CNS stimulation
• Today, the primary use of stimulants is for
ADHD in children and adolescents, residual
attention deficit disorder in adults, and
narcolepsy (attacks of unwanted but
irresistible daytime sleepiness that disrupt the
person’s life)
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Psychopharmacology: CNS stimulants for ADHD
• Examples: amphetamines –Dextroamphetamines (Dexedrine)
• Indications: narcolepsy (excessive daytime sleepiness) & ADHD
with hyperactivity in children & adults.
• Action: increase level of neurotransmitters (increase mental
alertness), diminish sense of fatigue.
Contraindications: hypersensitivity, cardiovascular diseases,
hyperthyroidism, and glaucoma.
Nursing diagnosis:
Risk for injury r/t hyperactivity
Risk for suicide r/t abrupt withdrawal after extended use
Sleep pattern disturbance overstimulation
• Nursing interventions for common side effects.
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Side effect
• The most common side effects of stimulants
are anorexia, weight loss, nausea, and
irritability. The client should avoid caffeine,
sugar, and chocolate, which may worsen these
symptoms.
• Less common side effects include dizziness,
dry mouth, blurred vision, and palpitations.
• The most common long-term problem with
stimulants is the growth and weight
suppression that occurs in some children
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Psychopharmacology: Nursing interventions
• Drowsiness: no driving, no working with machines,
• Tolerance: not to stop medication abruptly, not to take other
medications and alcohol,
• Physical: assess vital signs for tachycardia, monitor intake and
output, observe orthostatic hypotension, teach relaxation
techniques, report any abnormalities such as rash, observe
extrapyramidal symptoms, …
• Dry mouth: sips of water, sugar-free candy, ice, ..
• Nutrition: high fiber, milk, take drug with food or milk, oral
hygiene, physical exercise, avoid caffeinated food,
• Vision: not to drive, clear pathways.
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Client Teaching
• The potential for abuse exists with stimulants,
but this is seldom a problem in children.
• Taking doses of stimulants after meals may
minimize anorexia and nausea.
• Caffeine-free beverages are suggested; clients
should avoid chocolate and excessive sugar.
• Most important is to keep the medication out
of the child’s reach because as little as a 10day supply can be fatal.
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Other disorder
• The treatment of simple insomnia includes
antidepressants, benzodiazepines,
nonbenzodiazepines, over-the-counter medications,
barbiturates, and some miscellaneous substances.
The treatment of choice is the nonbenzodiazepines
because of their rapid absorption and efficient
elimination with little hangover effect.
• Acetylcholinesterase inhibitors are used to improve
or slow the decline of cognitive functioning and
memory problems in clients with dementia of the
Alzheimer’s type
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• Acetylcholinesterase inhibitors: These increase
available acetylcholine in the CNS, thus
improving cognitive functioning and memory.
The action is to decrease acetylcholinesterase,
an enzyme that breaks down acetylcholine
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Disulfiram (Antabuse)
• Disulfiram is a sensitizing agent that causes an
adverse reaction when mixed with alcohol in
the body.
• This agent’s only use is as a deterrent to
drinking alcohol in persons receiving
treatment for alcoholism.
• It is useful for persons who are motivated to
abstain from drinking and who are not
impulsive
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• Five to ten minutes after a person taking disulfiram
ingests alcohol, symptoms begin to appear: facial and
body flushing from vasodilation, a throbbing
headache, sweating, dry mouth, nausea, vomiting,
dizziness, and weakness.
• In severe cases, there may be chest pain, dyspnea,
severe hypotension, confusion, and
even death. Symptoms progress rapidly and last from
30 minutes to 2 hours. Because the liver metabolizes
disulfiram,
• it is most effective in persons whose liver enzyme
levels are within or close to normal range
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THANK YOU
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