What is Dopamine responsible for?
Involved in fine muscle movement; Involved in the integration of emotions
and thoughts; Involved in decision making; Stimulates hypothalamus to
release hormones (sex, thyroid, adrenal).
What is Norepinephrine responsible for?
Level in brain affects mood; Attention and arousal; Stimulates sympathetic
branch of autonomic nervous system for "fight or flight" in response to
stress
What is Serotonin responsible for?
Plays a role in sleep regulation, hunger, mood states, and pain perception;
Hormonal activity; Plays a role in aggression and sexual behavior
What is Histamine responsible for?
Involved in alertness; Involved in inflammatory response; Stimulates
gastric secretion
What is a Decrease in Dopamine responsible for?
Parkinson's disease and Depression
What is an Increase in Dopamine responsible for?
Schizophrenia and Mania
What is a Decrease in Norepinephrine responsible for?
Depression
What is an Increase in Norepinephrine responsible for?
Mania, Anxiety states, and Schizophrenia
What is a Decrease in Serotonin responsible for?
Depression
What is an Increase in Serotonin responsible for?
Anxiety states
What is a Decrease in Histamine responsible for?
Sedation and Weight gain
What is GABA (an amino acid) responsible for?
Plays a role in inhibition, reduces aggression, excitation, and anxiety; May
play a role in pain perception; Has anticonvulsant and muscle-relaxing
properties; May impair cognition and psychomotor functioning
What is a Decrease in GABA (an amino acid) responsible for?
Anxiety disorders, Schizophrenia, Mania, and Huntington's disease
What is an Increase in GABA (an amino acid) responsible for?
Reduction of anxiety
What is Glutamate (an amino acid) responsible for?
Is excitatory; Plays a role in learning and memory
What is an Increase in Glutamate (an amino acid) responsible for?
Prolonged increase state can be neurotoxic; Neurodegeneration in
Alzheimer's disease; Improvement of cognitive performance in behavior
tasks
What is a Decrease in Glutamate (an amino acid) responsible for?
Psychosis
What is Acetylcholine (anticholinergic) responsible for?
Plays a role in learning, memory; Regulates mood: mania, sexual
aggression; Affects sexual and aggressive behavior; Stimulates
parasympathetic nervous system
What is a Decrease in Acetylcholine (anticholinergic) responsible for?
Alzheimer's disease, Huntington's disease, and Parkinson's disease
What is an Increase in Acetylcholine (anticholinergic) responsible for?
Depression
What is Substance P (peptides) responsible for?
Promotes and reinforces memory; Involved in regulation of mood and
anxiety; Role in pain management
What is Somatostatin (peptides) responsible for?
Altered levels associated with cognitive disease
What is a Decrease in Somatostatin (peptides) responsible for?
Alzheimer's disease; some association with depression
What is an Increase in Somatostatin (peptides) responsible for?
Huntington's disease
What is Neurotensin (peptides) responsible for?
Endogenous antipsychotic-like properties
What are the adverse effects of Lithium?
Tremor, ataxia, confusion, convulsions, nausea, vomiting, diarrhea,
arrhythmias, polyuria, polydipsia, edema, goiter, and hypothyroidism
What are Neurons?
Nerve cells that respond to stimuli, conduct electrical impulses, and
release chemicals called neurotransmitters.
What are Circadian Rhythms?
The fluctuation of various physiological and behavioral parameters over a
24 hr cycle. Include body temp and sleep/wake cycle.
What is the Limbic System?
Areas of the cerebrum that play a crucial role in emotional status and
psychological function
What is the Brainstem responsible for?
Regulates the internal organs and is responsible for such vital functions as
the regulation of blood gases and the maintenance of blood pressure.
What is the Cerebellum responsible for?
Regulation of skeletal muscle coordination and contraction and the
maintenance of equilibrium.
What is the Cerebrum responsible for?
Mental activities and a conscious sense of being. Responsible for our
conscious perception of the external world, our own body, emotional
status, memory, control of skeletal muscles, language and the ability to
communicate
How are PET scans different from CT scans and MRIs?
PET scans can detect functional abnormalities in the brain while CT scans
and MRIs detect structural abnormalities in the brain.
What is Pharmacokinetics?
Refers to the actions of the person on the drug
What is Pharmacogenetics?
Explains how genetic variation leads to altered drug responses in different
individuals and ethnic groups
What do Benzodiazepines do?
They potentiate, or promote the activity of GABA by binding to a specific
receptor on the GABA(a) receptor complex. Examples include Valium,
Xanax, and Klonopin
What is occasionally combined with Benzodiazepines that needs to be
monitored for life threatening CNS depression?
Other CNS depressants such as alcohol, opiates, or tricyclic
antidepressants
What is Buspirone (BuSpar)?
A drug that reduces anxiety without having strong sedative-hypnotic
properties. It is not a CNS depressant and therefore does not have as
great a danger of interaction with other CNS depressants as
Benzodiazepines do.
What are Melatonin Receptor Agonists?
These drugs mimic the hormone Melatonin (that is only excreted at night
as part of the normal circadian rhythm) to help patient's fall asleep.
What are Tricyclic antidepressants (TCAs)?
Antidepressant. Drugs that are thought to act primarily by blocking the
reuptake of norepineprhine, therefore increasing the level of
norepinephrine at the synapse.
What are Selective Serotonin Reuptake Inhibitors (SSRIs)?
Antidepressant. Block the reuptake and the degradation of serotonin, but
each specific SSRI has a different effect on neurotransmitters.
What are Serotonin-Norepinephrine Reuptake Inhibitors?
Antidepressant. Drugs that increase Serotonin and Norepinephrine
What are Monoamine Oxidase Inhibitors (MAOIs)?
Antidepressant. Act by inhibiting the enzyme and interfering with the
destruction of the monoamine neurotransmitters (norepinephrine,
epinephrine, dopamine, serotonin, etc.), thereby leaving more of them
available.
What drugs are contraindicated with MAOIs?
Antidepressants, sympathomimetic drugs, and oral decongestants
What is Lithium used for?
A mood stabilizer in patients with bipolar disorder.
What is the Therapeutic Index?
The ratio of the lethal dose to the effective dose, and is a measure of
overall drug safety in regards to the possibility of overdose or toxicity.
What how do Anticonvulsant Drugs work?
They reduce the firing rate of very-high-frequency neurons in the brain;
which possibly accounts for their ability to reduce the mood swings that
occur in patients with bipolar disorders.
What is carbamazepine (Tegretol) used for?
Anticonvulsant. Useful in preventing mania during episodes of acute
mania. Reduces the firing rate of overexcited neurons by reducing the
activity of sodium channels.
What is lamotrigine (Lamictal) used for?
Anticonvulsant. Works well in treating the depression of bipolar disorder
with less incidence of switching the patient to mania than
antidepressants. Modulates the release of glutamate and aspartate.
What are First-Generation Antipsychotics?
Drugs that are strong antagonists (blocking the action) of Dopamine;
Target mostly the positive symptoms of schizophrenia
What are some side effects of First-Generation Antipsychotics?
Extrapyramidal symptoms; Sedation and Weight gain
What are Second-Generation Antipsychotics?
Drugs that predominantly block Dopamine and Serotonin. Produce fewer
extrapyramidal side effects; and target both the negative and positive
symptoms of schizophrenia; Increased chances of developing Metabolic
Syndrome *
What is a major side effect to watch for in patients taking Clozapine (a
2nd-generation antipsychotic)?
Agranulocytosis - requires constant measurement of WBC count
What are some side effects of Risperidone (Risperdal) a 2nd-generation
antipsychotic?
Motor difficulties (ex. extrapyramidal symptoms); Sedation; Orthostatic
hypotension; Weight gain
What is aripiprazole (Abilify)?
3rd-generation antipsychotic. Known as a dopamine system stabilizer.
Side effects include insomnia and akathisia
What drug class is used for patients with ADHD?
Psychostimulants
Function of the brain
Monitor changes in the external world, Monitor the composition of body
fluids, Regulate the contractions of the skeletal muscles, Regulate the
internal organs, Initiate and regulate the basic drives of hunger, thirst,
sex, aggressive self-protection, Mediate conscious sensation, Store and
retrieve memories, Regulate mood (affect) and emotions, Think and
perform intellectual functions, Regulate the sleep cycle, Produce and
interpret language, Process visual and auditory data.
Cerebrum
surface and deep areas of integrating gray matter (the cerebral cortex and
basal ganglia; neuronal cell bodies, dendrites, and glial cells) as well as
connecting tracts of white matter (link these areas with each other and the
rest of the nervous system; myelinated nerve fibers (axons)).
Progressive loss of both gray and white matter
linked with schizophrenia as well as use of antipsychotic medication.
Plasticity (change structurally and functionally as a result of input from
the environment.)
is evident throughout life as gray matter shrinks or thickens and synaptic
connections are pruned or forged, especially in areas where learning and
memory occur.
Each hemisphere of the cerebral cortex is divided into four lobes:
sensory and motor function as well as higher mental activities (e.g.,
language, decision making, problem solving, and a conscious sense of
being).
Sensory areas are responsible for specific sensations:
the parietal for touch, temporal for sound, and occipital for vision.
Frontal Lobe/Motor areas controls
voluntary movement.
Frontal lobe/ The prefrontal cortex (PFC)
coordinates complex cognitive functions (thought process) and enables us
to plan and execute goals, insight, motivation, social judgment, voluntary
motor ability starts here.
Frontal lobe/ When circuitry in the PFC is impaired by a mental disorder
(e.g., schizophrenia, major depression, or alcohol intoxication), there is
a decrease in:
executive function, attention, impulse control, socialization, regulation of
drives (such as libido), and emotions.
In addition to the gray matter forming the cortex, there are pockets of
integrating gray matter lying deep within the cerebrum: (3)
the hippocampus, the amygdala, and the basal ganglia.
Hippocampus interacts with the PFC for:
making new memories.
Amygdala plays a major role in:
processing fear and anxiety.
Parietal Lobe (sensory and motor)
receives and id's sensory information; concept formation and abstraction;
proprioception and body awareness; reading; mathematics, right and left
orientation.
occipital lobe
vision; interprets visual images, visual associations, visual memories,
involved with language formation.
temporal lobe
auditory; language comprehension, stores sounds into memory
(language/speech), connects with limbic system (emotional brain) to allow
expression of emotion (sexual, aggression, fear)
limbic system (emotional brain) 4 parts;
The hippocampus and amygdala, along with the hypothalamus and
thalamus, are part of a circle of structures
limic system links: Linking the:
frontal cortex, basal ganglia, and upper brainstem,
limbic system mediates:
thought and feeling through complex, bidirectional connections.
Antianxiety drugs (anxiolytics) slow the:
limbic system.
The four subcortical basal ganglia that lie deep within the cerebrum are
the
striatum, the pallidum, the substantia nigra, and the subthalamic nucleus.
basal ganglia plays major role in:
motor responses via the extrapyramidal motor system: regulates
movement including the diaphragm and muscles of the throat, tongue and
mouth.
dopamine- a neurotransmitter (basal ganglia)
maintain proper muscle tone and motor stability (extra pyramidal motor
system of basal ganglia).
Haloperidal (an antipsychotic agent) can:
reduce striatal (one of four basal ganglia) volume within hours,
temporarily changing brain structure and predicting abnormal involuntary
motor symptoms (extrapyramidal symptoms [EPS]).
In the basal ganglia, two types of movement disturbances may occur:
(1) acute extrapyramidal symptoms, which develop early in treatment; and
(2) tardive dyskinesia, which usually occurs much later.
These types of antipschotics are most likely to cause extrapyramidal
side effects:
Conventional antipsychotics (the first generation of antipsychotic
medications) and high doses of the atypical agent (second generation of
antipsychotic medications) risperidone (Risperdal)
Drugs that affect brain function can stimulate or depress:
respiration or affect speech patterns (e.g., slurred speech).
brainstem (composed of the midbrain, pons, and medulla)
basic vital life functions
Reticular activating system (RAS), in the brainstem:
sets the level of consciousness and regulates the cycle of sleep and
wakefulness.
drugs used to treat psychiatric problems may interfere with
the regulation of sleep and alertness, thus the warning to take sedating
drugs at bedtime and to use caution while driving.
Cerebellum
coordinator of motor function; interacts with the cerebrum in higher
cognitive functions(speech memory, facial recognition, visual attention,
and awareness)
Cerebellar hypoactivation
affecting posture and equilibrium is well-documented as occurring in
some people with schizophrenia.
Thalamus (above brain stem)
major relay station for sensory impulses on their way to the cerebral
cortex; plays a role in complex reflex movements, body-alerting
mechanisms, and even emotions by associating sensory impulses with
various feelings.
Dopamine (thalmus)- monoamine
Reduces the thalamic sensory filter, allowing more sensory input to
escape from the thalamus to the cortex:
Fine muscle movement, Integration of emotions and thoughts, Decision
making, Stimulates hypothalamus to release hormones (sex, thyroid,
adrenal)
Increase:Schizophrenia, Mania
Decrease:Parkinson's disease, Depression
Corticostriatal-thalamic pathways are disrupted in:
schizophrenia, obsessive-compulsive disorder (OCD), and attention
deficit/hyperactivity disorder (ADHD).
hypothalamus maintains
homeostasis by regulating temperature, blood pressure, perspiration,
libido, hunger, thirst, and circadian rhythms, such as sleep and
wakefulness.
Hypothalamic neurohormones, often called releasing hormones, direct
the secretion of hormones from the anterior pituitary gland. For example,
corticotropin-releasing hormone (CRH) is involved in the stress response.
It stimulates the pituitary to release corticotropin, which in turn stimulates
the cortex of each adrenal gland to secrete cortisol.
hypothamlamic neurohormones is disrupted in
mood disorders, posttraumatic stress disorder (PTSD), and Alzheimer's
dementia.
The hypothalamic-pituitary-thyroid axis is involved in
the regulation of nearly every organ system because all major hormones
and catecholamines (e.g., cortisol, gonadal hormones, insulin) depend on
thyroid status.
Release of thyrotropin-releasing hormone (TRH) results in
pituitary secretion of thyrotropin (thyroid-stimulating hormone or TSH),
which in turn stimulates the thyroid gland to release the thyroid
hormones—thyroxine (T4) and triiodothyronine (T3).
Thyroid hormones are used to treat people with
depression or rapid-cycling bipolar I disorder. Also used as replacement
therapy (lithium).
hypothyroid state is a result of
Lithium treatment and need thyroid hormone replacement therapy.
hypothalamic neurohormone dopamine inhibits...
the release of prolactin.
dopamine blocked by conventional antipsychotic drugs
blood prolactin levels increase (hyperprolactinemia) with subsequent
amenorrhea, galactorrhea (milk flow), gynecomastia (development of
breast tissue), or sexual dysfunction(conventional agents and the atypical
drug risperidone )
hypothalamus sends instructions to
the autonomic nervous system,
autonomic nervous system
divided into the sympathetic and parasympathetic systems
sympathetic system usually
increases heart rate, respirations, and blood pressure to prepare for fight
or flight, The sympathetic system is highly activated by sympathomimetic
drugs, such as amphetamine and cocaine, as well as by withdrawal from
sedating drugs, such as alcohol, benzodiazepines, and opioids
parasympathetic system
slows the heart rate and begins the process of digestion.
Neuroimaging
visualizes a brain that is structurally and functionally interconnected.
Structural imaging techniques are
computed tomography (CT) and magnetic resonance imaging (MRI).
CT scans use
a series of x-rays to view brain structure.
MRI scans
use a strong magnetic field and radio waves, distinguishing gray and
white matter better than CT scans.
Functional neuroimaging with positron emission tomography (PET) and
single photon emission computed tomography (SPECT) use
use ionizing radiation to localize brain regions associated with perceptual,
cognitive, emotional, and behavioral functions.
Based on the increase in blood flow to the local vasculature that
accompanies neural activity, PET scans
have provided evidence of decreased metabolism in unmedicated
individuals with depression or schizophrenia and increased metabolism in
obsessive-compulsive disorder.
PET and SPECT have also shown
Can detect oxygen utilization, glucose metabolism, blood flow,
neurotransmitter receptor interaction; dopamine system dysregulation in
schizophrenia and loss of monoamines in depression (Blockade of
serotonin transporter receptors with antidepressant medications);
Alzheimer's disease: reduction in nicotinic receptor subtype
Functional magnetic resonance imaging (fMRI) demonstrates :
cognitive function without contrast injections or invasive tests:
It is the major method used by cognitive neuroscientists to observe
changes that occur in f the brain while subjects perform tasks involving
higher intellectual processes (memory/attention).
fMRI maps the modulatory effects of psychotropic medication,
illustrating
how a therapeutic response can be achieved at minimal doses.
Antipsychotic medications are now prescribed at a fraction of the dosages
that were once considered standard, in large part because of imaging
studies.
neurotransmission is:
ability of neurons to initiate signals and conduct an electrical impulse
from one end of the cell to the other
synapses
convert Electrical signals within neurons into chemical signals through the
release of molecules called neurotransmitters, then elicit electrical signals
on other side of the synapse. Together, action potentials and synaptic
signals enable information processing in the brain.
schizophrenia causes...
excessive transmission may be due to excessive release of a transmitter
or to increased receptor responsiveness.
dopamine:
neurotransmitter is a
chemical messenger between neurons by which one neuron triggers
another.
Four major groups of neurotransmitters in the brain are
monoamines (biogenic amines), amino acids, peptides, and cholinergics
(e.g., acetylcholine).
Monoamine neurotransmitters (dopamine, norepinephrine, serotonin)
and acetylcholine are
implicated in a variety of neuropsychiatric disorders.
Amino acid neurotransmitters, such as the inhibitory γ-aminobutyric
acid (GABA) and the excitatory glutamate, .
balance brain activity
Peptide neurotransmitters such as hypothalamic CRH can
be thought of as modulating or adjusting general
Computed tomography (CT)
"slices," providing a 3D-like reconstruction of each segment and can
detect lesions, abrasions, areas of infarct, aneurysm: Schizophrenia,
Gray matter reduction, Ventricle abnormalities
Magnetic resonance imaging (MRI)
Uses a magnetic field and radio waves to produce cross-sectional images;
Used to exclude neurological disorders in those presenting with mental
illness (schizophrenia)
Functional magnetic resonance imaging (fMRI)
Relies on magnetic properties to see images of blood flow in brain as it
occurs; avoids exposure to radioactive isotypes; Can detect edema,
ischemia, infection, neoplasm, trauma;
psychotropic drugs produce effects through
alteration of synaptic concentrations of dopamine, acetylcholine,
norepinephrine, serotonin, histamine, GABA, or glutamate. (through
receptor antagonists-blocking activity of a neurotransmitter) or agonists
(promoting activity of a neurotransmitter), interference with
neurotransmitter reuptake, enhancement of neurotransmitter release, or
inhibition of enzymes.
Dopamine (monoamine) -reuptake
neurotransmitter involved in cognition, motivation, and movement.
Controls emotional responses and the brain's reward and pleasure
centers,
stimulates the heart, and increases blood flow to vital organs.
Cocaine (like drugs) interfere with...
reuptake of dopamine, thereby allowing more of the neurotransmitter to
stay active in the synapse for a longer time.
dopamine hypothesis of schizophrenia
observation that drugs (e.g., amphetamines) that stimulate dopamine
activity can induce psychotic symptoms whereas drugs that block
dopamine receptors (e.g., haloperidol) have antipsychotic activity.
acetylcholine (neurotransimtter)
balances dopamine.
Neurons that release acetylcholine
are cholinergic: thought to be involved in cognitive functions, especially
memory.
Alzheimers
Acetylcholine is deficient in Alzheimer's disease, attempts have been
made to enhance the function of neurons that secrete acetylcholine by use
of drugs that inhibit the enzyme that degrades acetylcholine (i.e.,
acetylcholinesterase). Therefore acetylcholinesterase (AChE) inhibitors are
prescribed to delay cognitive decline in Alzheimer's disease.
norepinephrine (NE)- monoamine/reuptake
called noradrenergic; NE and serotonin play a major role in regulating
mood, attention/arousal, fight or flight (sympathetic system).
A deficiency within the limbic system is thought to underlie depression,
whereas an excess has been associated with mania, anxiety,
schizophrenia.
NE or serotonin BLOCK can cause (monoamine)
vasodilation and a consequent drop in blood pressure, or orthostatic
hypotension. The α1 receptors are also found on the vas deferens and are
responsible for the propulsive contractions leading to ejaculation.
Blockage of these receptors can lead to a failure to ejaculate. deficiency of
one/both may underlie depression
serotonin found in/helps (reuptake)
brain and spinal cord, helps regulate mood, arousal, attention, behavior,
and body temperature. Increase: Anxiety states
Decrease:Depression
serotonin syndrome
serotonin increased (antidepressants mixed with St. Johns wort or
dextromethorphan)
Symptoms of high levels of serotonin range from mild (restlessness,
shivering, and diarrhea) to severe (muscle rigidity, fever, and seizures).
These symptoms can be alleviated by muscle relaxants and drugs that
block serotonin production. Current research focuses on serotonin
dysfunction in impulsive aggression and suicide (Cardish, 2007).
Platelet Serotonin release
plays an important role in hemostasis
Histamine (H1, H2)- monoamine
Increase: Alertness, Inflammatory response, ^ gastric secretion.
Decrease: Sedation, Weight gain.
γ-Aminobutyric acid (GABA); GABAA; GABAB-amino acid
Inhibitory neurotransmitter:
Reduces anxiety, excitation, aggression;
May play a role in pain perception
Anticonvulsant and muscle-relaxing properties
May impair cognition and psychomotor functioning
Increase: Reduction of anxiety
Decrease: Mania, Anxiety, Schizophrenia
Glutamate (NMDA, AMPA)- amino acid
Excitatory neurotransmitter:
AMPA plays a role in learning and memory
Increase AMPA: Improvement of cognitive performance in behavioral
tasks
Increase NMDA: Prolonged increase can kill neurons (neurotoxicity)
Neurodegeneration in Alzheimer's disease
Decrease NMDA: Psychosis
Acetylcholine (ACh): Nicotinic, muscarinic (M1, M2, M3)
cholinergic
Plays a role in learning, memory
Regulates mood: mania, sexual aggression
Affects sexual and aggressive behavior
Stimulates parasympathetic nervous system
Decrease: Alzheimer's disease, Huntington's chorea, Parkinson's
Increase: Depression
Substance P (SP) cholinergic
Centrally active SP antagonist has antidepressant and antianxiety effects
in depression
Promotes and reinforces memory
Enhances sensitivity to pain receptors to activate
Involved in regulation of mood and anxiety
Role in pain management
Somatostatin (SRIF) -cholinergiv
Altered levels associated with cognitive disease
Decrease:Alzheimer's disease Decreased levels of SRIF in spinal fluid of
some depressed patients
Increase: Huntington's chorea
Neurotensin (NT)
Endogenous antipsychotic-like properties
Decreased levels in spinal fluid of schizophrenic patients
combining selective serotonin reuptake inhibitors (SSRIs) and
antipsychotics produces changes in GABAA receptors
produce synergism significantly improves negative symptoms in patients
unresponsive to antipsychotic treatment.
Pharmacokinetic interactions
are the effects of drugs on the plasma concentrations of each other.
when a potent CYP450 enzyme inhibitor or inducer is added to drugs
metabolized by one or more CYP450 enzymes,
the patient experiences an adverse drug effect or therapeutic failure.
Pharmacodynamic interactions are
the combined effects of drugs. additive or synergistic effect ;alcohol is
taken with psychotropic medications.
Monoamines:
a type of organic compound, including the neurotransmitters
neurotransmitters that are further divided into subgroups called
catecholamines (e.g., norepinephrine, epinephrine, dopamine) and
indolamines (e.g., serotonin) and many different drugs and food
substances
Monoamine oxidase (MAO):
an enzyme that destroys monoamines
Monoamine oxidase inhibitors (MAOIs):
drugs that increase concentrations of monoamines by inhibiting the action
of MAO
MAOIs block the enzyme that metabolizes monoamines,
they may occasionally be used to increase the levels of serotonin and
norepinephrine in intractable depression.
MAOIs combined with other sympathomimetics (amines that stimulate
the sympathetic nervous system).
vasopressor effects that occur (constriction of blood vessels).
hypertensive crisis
If a patient takes over-the-counter medications with pseudoephedrine or
consumes the adrenergic monoamine tyramine, commonly found in aged
foods and beverages.
selective serotonin reuptake inhibitors (SSRIs) and serotoninnorepinephrine reuptake inhibitors (SNRIs)
preferred over MAOI's
MAOI'S nursing teaching
do not take with thiamine containing foods to avoid hypertensive crisis.
(including 2 wks after stopping MAOI's
Tricyclic Antidepressants (TCAs)
act primarily by blocking the presynaptic transporter protein receptors for
norepinephrine and, to a lesser degree, serotonin: blocking prevents
norepinephrine from coming into contact with its degrading enzyme,
MAO, and thus increases the level of norepinephrine at the synapse. (ex:
such as amitriptyline (Elavil) and nortriptyline (Pamelor))
TCAs treat
difficult cases of depression and chronic pain
TCA side effects
side effects: anticolinergic effects(dry up) block H1 receptors, causing
sedation and weight gain.
Strong binding at adrenergic receptors causes dizziness and hypotension,
thereby increasing the risk for falls
Selective Serotonin Reuptake Inhibitors (SSRIs)
preferentially block the reuptake and thus the destruction of serotonin.
[fluoxetine (Prozac), sertraline (Zoloft), paroxetine (Paxil), citalopram
(Celexa), and escitalopram (Lexapro)]
Serotonin ^^^ while taking SSRI's
can result in anxiety, insomnia, sexual dysfunction, and gastrointestinal
disturbances.
Serotonin toxicity
occur with coadministration of other serotonergic drugs (e.g., MAOIs,
SSRIs, SNRIs, lithium, triptan, buspirone, tramadol, over-the-counter
cough and cold medications containing dextromethorphan) or
antidopaminergic drugs.
SSRI discontinuation= discontinuation syndrom
when discontinuation is abrupt; most likely to occur with SSRIs or SNRIs
having a short half-life. Thus it is more common with paroxetine (Paxil)
than with fluoxetine (Prozac).
Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs)
increase the levels of both serotonin and norepinephrine.
Venlafaxine (Effexor)
is more of a serotonergic agent at lower doses, but norepinephrine
reuptake blockade occurs at higher doses, leading to the dual SNRI action.
Duloxetine (Cymbalta)
is used for depression and pain associated with diabetic neuropathy.
Serotonin-Norepinephrine Disinhibitors (SNDIs)
mirtazapine (Remeron), increase norepinephrine and serotonin
transmission by blocking presynaptic α2-noradrenergic receptors.
Mirtazapine: antianxiety and antidepressant effects, with minimal sexual
dysfunction secondary to serotonin blockade.
This is an antiemetic via serotonin blockade.
Norepinephrine-Dopamine Reuptake Inhibitors (NDRIs)
bupropion (Wellbutrin); inhibits dopamine-norepinephrine reuptake, also
inhibits nicotinic acetylcholine receptors to reduce the addictive action of
nicotine. (used for smoking cessation)
Antidepressants also treat...
anxiety disorders because of shared symptoms, neurotransmitters, and
circuits.
SSRIs are commonly used to treat
panic disorder, generalized anxiety disorder (GAD), OCD, PTSD, and social
phobia.
GAD=
generalized anxiety disorder.
SNRIs venlafaxine (Effexor) and duloxetine (Cymbalta) are also used to
treat
GAD
GABA IS...
major inhibitory (calming) neurotransmitter in the CNS.
benzodiazepines (diazepam (Valium), clonazepam)
The most commonly used antianxiety agents, reduce neuronal excitement
in seizures and alcohol withdrawal.
Romote activity of GABA by binding to a specific receptor on the GABAA
receptor complex.
limited potential for toxicity; potential for tolerance and withdrawal.
Non-Benzodiazepines (Buspirone)
Reduces anxiety without having strong sedative-hypnotic properties.
high affinity for serotonin receptors, acting as a serotonin
Not a CNS depressant and thus not great danger of interaction with
other CNS depressants, such as alcohol.
The potential for addiction that exists with benzodiazepines does not
exist for buspirone.
Short-Acting Sedative-Hypnotic Sleep Agents: zolpidem (Ambien),
zaleplon (Sonata), and eszopiclone (Lunesta),
demonstrate selectivity for GABAA receptors containing α1 subunits. Have
sedative effects without the antianxiety, anticonvulsant, or muscle
relaxant effects of benzodiazepines.
Mood Stabilizers: Lithium
treatment for bipolar disorder is well established
Long-term use of lithium increases the risk of both kidney and thyroid
disease.
Mood Stabilizers: Anticonvulsant-Valproate
divalproex sodium (Depakote) and valproic acid (Depakene), is
recommended in bipolar disorder for mixed episodes and rapid cycling
and managing impulsive aggression.
Baseline lab work includes liver function tests and complete blood count
(CBC).
Valproate levels are measured every 6 months and generally range from
50 to 100 mcg/mL.
Mood Stabilizers: Anticonvulsant-Carbamazepine (Tegretol)
Treats acute mania.
A CBC must be done periodically because of rare but serious blood
dyscrasias (e.g., aplastic anemia and agranulocytosis).
Mood Stabilizers: Anticonvulsant-Lamotrigine (Lamictal)
Maintenance treatment of bipolar disorder, effective in decreasing the
time between episodes of bipolar depression.
The most common adverse effects are usually mild,develop a rash during
the first 4 months of treatment. possibly a toxic epidermal necrolysis
called Stevens-Johnson syndrome
Cross-cultural psychopharmacology
explores different effects/responses that exist among ethnic groups and
the reasons for these effects.
predict patients' responses, scientists search for variants in genes that
code for drug metabolizing enzymes in the liver.
Pharmacogenetics
studies how genes influence drug metabolism and response.
KP-actions of the brain
sensory, motor, intellectual—are carried out physiologically through the
interactions of nerve cells.
These interactions involve impulse conduction, transmitter release, and
receptor response.
KP-Alterations in Basic BRAIN processes can lead to
mental disturbances and physical manifestations.
KP-excess activity of dopamine
is involved in the thought disturbances of schizophrenia, and deficiencies
of norepinephrine, serotonin, or both underlie depression and anxiety.
Insufficient activity of GABA also plays a role in anxiety.
KP- Pharmacological treatment of mental disturbances is directed at the
suspected transmitter-receptor problem.
Antipsychotic drugs decrease dopamine levels, antidepressant drugs
increase synaptic levels of norepinephrine and/or serotonin, and
antianxiety drugs increase the effectiveness of GABA or increase 5-HT
and/or norepinephrine levels.
KP- immediate target activity of a drug can result in
many downstream alterations in neuronal activity, drugs with a variety of
chemical actions may show efficacy in treating the same clinical condition.
newer drugs with novel mechanisms of action are being used in the
treatment of schizophrenia, depression, and anxiety.
KP-agents used to treat mental disease can cause various undesired
effects.
sedation/Excitement, motor disturbances, muscarinic blockage, αadrenergic antagonism, sexual dysfunction, and weight gain.
Q1 All mental activity has its locus in the:
BRAIN
Q2 Standard anti-psychotic drugs:
lower the seizure threshold; can cause extrapyramidal symptoms (EPS),
AND may lead to neuroleptic malignant syndrome.
Q3 The patients who should be most carefully assessed for untoward
cardiac side effects are those receiving:
LITHIUM
Q4 Clozaril:
is an atypical anti-psychotic drug AND may cause agranulocytosis.
Q5 Pharmacological agents:
may have undesired effects in some cultural groups.