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Nervous System/Adrenergic & Blocking Agents
Nervous System Adrenergic (Sympathomimetic) Agents are used to
treat breathing disorders such as Asthma, Emphysema, or Chronic
Bronchitis. Nervous System Adrenergic Blocking (Sympatholytic)
Agents are used to treat symptoms of migraine headaches.
with other cells throughout the body by releasing chemicals,
such as epinephrine and norepinephrine, into the synapse
exciting receptors. Another neuron responds to the chemicals in
the synaptic junction by sending electrical impulses to various
organs. Stimulation from epinephrine and norepinephrine results
in cerebral vessel dilatation, increased heart rate and
strength, peripheral blood vessel constriction, airway
relaxation, decreased intestinal activity, bladder relaxation,
urinary sphincter contraction, and increased production of
saliva. A feedback system limits excess release of chemicals to
prevent prolonged stimulation of the various organs.
In diseases, such as asthma, bronchitis, or emphysema, airways
become constricted due to smooth muscle spasms and inflammation
so breathing becomes hampered. Migraines occur when cerebral
vessels constrict, spasm, and eventually dilate. The Migraine
Headache pain is caused by continual cerebral vessel dilatation.
Sympathomimetic (Adrenergic) Agents, like Bronchodilators, relax
the smooth muscles and dilate the airways to improve breathing.
Bronchodilators, such as Adrenalin, Epinephrine, Alupent, or
Albuterol, imitate epinephrine and norepinephrine or trigger the
release of more natural epinephrine and norepinephrine for
airway dilatation. Pseudoephedrines relieve congestion due to
inflammation and assist in opening the air passageways.
Sympatholytic (Adrenergic Blocking) Agents, like Cafergot, can
be used to treat migraine headaches. They inhibit the chemical
release of epinephrine or norepinephrine resulting in
constriction of the already dilated cerebral vessels.
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Nervous System/Anticonvulsants, Sedatives, &
Nervous System Anticonvulsants,
Sedatives, & Hypnotics are used to depress brain activity and
treat sleeplessness, anxiety, nervousness, and seizures.
The brain consists
of many cells, called neurons, that communicate with other cells
throughout the body. Neurons are made of three major parts: the
cell body, axon, and dendrite. To communicate messages, the
neuron transmits electrical impulses that trigger chemicals to
be released. Chemicals (also known as neurotransmitters) such as
norepinephrine, dopamine, serotonin, and others, are released
into a region between two neurons, called the synapse. Another
neuron responds to the chemicals in the synaptic junction by
inhibiting or sending the electrical signal. The electrical
signals in the brain are usually organized to produce smooth
movements. Once the receiving cell has responded, the chemicals
remaining in the synaptic junction are either broken down by
enzymes or retaken up by the transmitter cell.
Normal sleep occurs with fatigue and reduced stimulation.
However, if excessive electrical impulses are triggered,
disorganization, increased chemical release, and altered brain
functioning occurs resulting in sleeplessness (or insomnia).
Anxiety can be caused by unorganized or excessive electrical
impulses producing tensions, inability to relax, shakiness,
sweating, racing heart, feelings of apprehension, lack of
concentration, insomnia, and other negative effects. Epilepsy,
or seizures, can result from disorganization of electrical
impulses, producing uncontrolled muscle activity, spasms,
unconsciousness, or loss of bowel or bladder control.
Anticonvulsants, Anxiolytics, Sedatives, and Hypnotics can be
used to treat anxiety, insomnia, or seizures. Neuronal
excitability is diminished by these medications by decreasing
impulse transmission and returning body movements to a more
organized smooth state, relaxation, or sleep. The medications
decrease the spread of the neuronal activity, reorganizing
impulse formation, chemical release or response, synaptic
response, or receiver cell response so messages are acted upon
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Nervous System/Antidepressants, Tranquilizers &
Nervous System Antidepressants, Tranquilizers and Other Agents
alter the chemicals in the brain to treat symptoms of
Depression, Manic-Depression, Psychosis or Schizophrenia.
The brain consists of many cells, called neurons, that
communicate with other cells throughout the body. Neurons are
made of three major parts: the cell body, axon, and dendrite. To
communicate messages, the neuron transmits electrical impulses
that trigger chemicals to be released. Chemicals (also known as
neurotransmitters) such as norepinephrine, dopamine, serotonin,
and others, are released into a region between two neurons,
called the synapse. Another neuron responds to the chemicals in
the synaptic junction by excitement or with inhibition. Once the
receiving cell has responded, the chemicals remaining in the
synaptic junction are either broken down by monoamine oxidase
enzymes or retaken up by the transmitter cell.
Alterations in neuronal cell function can influence
psychological behaviour. Depression can be caused by decreased
chemical levels, especially serotonin and norepinephrine. On the
other hand, Psychosis, Schizophrenia, or other mental illnesses
can be caused by increased chemical (mainly dopamine) activity
in the synapse. Manic-Depression, characterized by severe mood
swings from elation to depression, may be caused by variable
chemical extremes in the synapse and shifting inside the neuron.
Antidepressants, specifically Tricyclics and MAO Inhibitors, can
be used to treat depression. Tricyclics redirect excitatory
chemicals for use in the synapse to stimulate or excite other
neurons. MAO Inhibitors block enzymes that break down chemicals,
allowing further activity or excitement to occur in the synapse.
Tranquilizers, specifically Phenothiazines, cause calming
effects or sedation for Psychosis, Schizophrenia, or other
mental illnesses. They decrease the transmission of the nerve
signals by blocking the chemicals, especially dopamine, at
targeted receptor sites.
Antimanic Agents, like Lithium, can be used to treat
Manic-Depression by altering the elements in the cell,
stabilizing nerve impulse transmission and chemical release.
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Nervous System/Cholinergic and Anti cholinergic
Nervous System Cholinergic and Anticholinergic Agents are used
to stimulate or reduce certain body functions and movements.
They are used in the treatment of Urinary Retention, Myasthenia
Gravis, Diarrhoea, Cramps, Nervous Stomach, Ulcers, or
The Parasympathetic Nervous System is made up of neurons that
communicate with other cells in the body by releasing chemicals
into the synapse to excite receptors and send electrical
impulses. The chemicals, primarily Acetylcholine, alter the
system, resulting in decreased heart rate and strength, airway
and pupil constriction, muscle and bladder contraction (with
sphincter relaxation), increased intestinal wall activity, and
an increase in saliva and insulin secretion. Once the receiving
cells respond, any acetylcholine still in the synaptic junction
is broken down by acetylcholinesterase that temporarily
diminishes the effects.
Prolonged diminished acetlycholine effects may cause disorders
like urinary retention, gastric reflux, or Myasthenia Gravis.
Urinary retention can occur due to lack of stimulation to the
bladder muscle and lack of sphincter relaxation. Gastric reflux
occurs when stomach secretions and food are forced up the
digestive tract instead of down to be digested. Myasthenia
Gravis is due to weakened skeletal muscles causing decreased
Cholinergic (Parasympathomimetic) Agents, like Bethanechol,
Mestinon, or Prostigmin, can be used to stimulate bladder
contraction, digestive tract movement, and skeletal muscle
movement. Cholinergic Agents imitate Acetylcholine or inhibit
acetylcholinesterase to prevent acetylcholine breakdown.
Parkinson's Disease can occur when an imbalance of acetylcholine
and dopamine neurotransmitters result in tremors or shaking,
increased muscle tone and rigidity, expressionless face,
drooling, and an unstable standing position. Increased
neurotransmission occurs when excitable acetylcholine levels are
raised and relaxant dopamine levels are decreased. Digestive
disorders can occur due to acetylcholinergic effects of
increased stomach or intestine activity causing Peptic Ulcers,
Diarrhoea, Irritable Bowel Syndrome, Cramps, or Nervous Stomach.
Parkinson's Disease symptoms can be reduced with Anticholinergic
Agents, such as Cogentin or Artane, which oppose acetylcholine
actions to regain balance with dopamine. Anticholinergic Agents
relax muscles, decreasing tremors, shaking, and rigidity. They
also decrease salivary secretions. Anticholinergic Agents, like
Belladonna, Anaspas, Levsin, Bentyl, and Rubinul, inhibit
acetlycholine and decrease stomach and intestinal activity.
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Nervous System/Skeletal Muscle Relaxants
Nervous System Skeletal Muscle Relaxants
prevent muscle spasms that can occur with Strains, Sprains,
Spinal Cord Injury, or Multiple Sclerosis.
Skeletal Muscles, attached to bones, provide body movement or
contraction in response to nerve stimulation. The brain and
spinal cord communicate through nerves to muscle cells for
contraction. The nerve impulses release chemicals (mainly
acetylcholine) at the nerve-muscle junction (called synapse),
causing excitement and sending electrical messages to the rest
of the muscle group to shorten or contract. Acetylcholine
remaining in the junction after the muscle contracts is
destroyed by other chemicals allowing muscle relaxation. The
muscle movements normally are voluntary, conscious, and smooth.
If chemical release continues, skeletal muscles remain
contracted, resulting in involuntary muscle spasms, causing
decreased functioning and pain. This can occur with spinal cord
injury, strains or sprains of muscles, or with a disease like
Skeletal Muscle Relaxants can decrease muscle spasms by
restricting the nervous pathway to the muscle. This interruption
of impulse transmission can occur in the brain, spinal cord,
neuron, nerve-muscle junction, or in the muscle. Most Skeletal
Muscle Relaxants act by depressing the brain pathways or
interfering with chemical activity in the nerve-muscle junction.
However, Dantrium directly inhibits muscle cellular calcium
movement to prevent contraction.
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Nervous System Stimulants are used to
treat Obesity, Narcolepsy, or Attention Deficit Disorder. These
drugs, often also called Stimulants and Appetite Suppressants,
make the brain active, resulting in alertness, increased
attention span, and decreased appetite.
Appetite and alertness are controlled by the brain stem. More
specifically, the reticular activating system, the thalamus, and
the hypothalamus signal the release of chemicals (called
norepinephrine) that trigger electrical activity resulting in
alertness and suppressed appetite. Other environmental stimuli,
such as smell, blood sugar, physical fitness, or fatigue can
influence the release of these chemicals.
If the brain stem malfunctions, chemical release may be limited
and cause one of the following diseases. Obesity can occur when
the satiety centre in the brain lacks stimulation to cease
eating or transmit the feeling of being full. Narcolepsy is the
tendency to fall asleep during the day. Attention Deficit
Disorder, a childhood disease, occurs when the brain chemicals
are disorganized and not read appropriately by the brain,
causing decreased attention span and concentration, increased
impulsiveness, and, occasionally, hyperactivity
Cerebral Stimulants, such as Amphetamines, Nonamphetamine
Stimulants, or Appetite Suppressants, can be used for
Narcolepsy, Obesity, and Attention Deficit Disorder. Cerebral
Stimulants activate the brain to release chemicals
(norepinephrine) and enhance electrical activity resulting in
alertness, euphoria, increased attention span or concentration,
and decreased appetite.
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Pain Agents are also known as
Analgesics and are manufactured in different strengths to
control varying degrees of pain. Some of these medications
(Antipyretics) also reduce fever.
To communicate pain,
nerves transmit electrical impulses that trigger chemical
release (mainly prostaglandins) into a region called the
synapse. Another nerve cell responds to the chemicals in the
synaptic junction and transmits the pain message to the brain.
Brain cells, called neurons, communicate with other cells
throughout the body and release a natural opiate-like chemical
(endorphins) to excite opioid receptors on the end of nerve
cells. Endorphins interrupt the pain message travelling to the
brain by inhibiting release of other neurotransmitters. Pain is
a very complex phenomenon that involves physiological,
psychological, cultural, and other factors. Pain can be a
warning symptom or protective mechanism warning the individual
of a problem.
If pain is not inhibited by the natural endorphins released in
the body, medications can be used to decrease pain sensitivity
or increase pain tolerance. The need for Pain control will vary
among individuals. Analgesics are drugs used to relieve the
symptoms of pain. Nonsteroidal Anti-Inflammatory Agents
(NSAIDS), are further divided into those made of salicylate
(like Aspirin) and those constituted of non-Aspirin compounds,
(like Ibuprofen). NSAIDS decrease pain sensation by generally
inhibiting prostaglandin production, which is responsible for
inflammation. This, in turn, also decreases redness, heat, or
swelling. Refer to ANTI-INFLAMMATORY AGENTS and DENTAL AGENTS
for more information. NSAIDS also alter the hypothalamus in the
brain, which decreases temperature. Additionally, Aspirin and
Aspirin compounds prevent blood clotting and can be useful to
prevent strokes and other diseases.
Narcotic Analgesics and Acetaminophen act directly, like natural
endorphins, to inhibit prostaglandins in the brain and spinal
cord, altering the pain perception. Narcotic Analgesics, such as
Morphine, Meperidine, Codeine, or Methadone, are also called
opioids and function by combining with opiate receptors at nerve
endings to block pain signals.
Opiate Antagonists, such as Naloxone or Narcan, reverse action
of narcotic drugs and natural endorphins in nerve endings. These
medications can be used for narcotic overdose or reversal of
respiratory depression caused by opiates.
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Respiratory Antitussives, Expectorants, & Mucolytics
Respiratory Antitussives, Expectorants, and Mucolytics are used
to treat secretions and cough occurring with the common cold,
allergies, hay fever, sinus infection, bronchitis, pneumonia,
asthma, or emphysema.
oxygen to be exchanged with carbon dioxide in the alveoli of the
lungs to give the cells energy. Air enters into the nose and
throat for natural humidifying and purifying before being sent
to the lungs. Tiny hairs inside the nose and upper respiratory
tract (called cilia), act as a screen to foreign particles.
Specialized cells in the respiratory tract produce mucus to stop
or trap any foreign particles that slip past this hair screen.
If foreign particles make their way past the cilia and into the
lower respiratory tract, coughing may occur to defend the
passageways. This is a natural defensive reflex to rid the
respiratory tract of foreign particles or secretions so air can
be transported freely. Cough is initiated locally by stimulation
or irritation of receptors in the respiratory tract walls that
send messages to the central respiratory centre in the medulla
of the brain.
Failure of mucus production or cough mechanisms may allow
foreign particles to invade and cause illness. Illnesses such as
the common cold, asthma, bronchitis, allergies, hay fever,
sinusitis, emphysema, or pneumonia cause symptoms of increased
cough or mucus production. A productive cough to rid the airways
of mucus or foreign particles can be irritating, painful, or
exhausting. Non-productive or dry cough usually occurs due to
irritation of the airways but does not clear secretions.
ANTITUSSIVES, EXPECTORANTS, AND MUCOLYTIC AGENTS can reduce
discomfort of respiratory illness by decreasing the symptoms of
cough or mucus. The cause of cough or increased mucus, such as
inflammation or infection, is typically treated first. Then,
Mucolytics, such as Acetylcysteine, are usually given by
inhalation for direct action on the respiratory tract to thin
mucous secretions by breaking them up. This usually makes it
easier to expel the secretions. Expectorants, such as
Guaifenesin, Iodinated Glycerol, or Potassium Iodide,, increase
production of mucus to trap foreign particles and excrete them
by a productive cough.
Antitussives can suppress a non-productive cough. Narcotic
Antitussives, such as Codeine, Hydrocodone, or Hydromorphone act
centrally to depress the medullary respiratory centre in the
brain to decrease cough. Some of the Narcotic Antitussives may
also decrease the ciliary action. Synthetic Antitussives, like
Dextromethorphan, act like Narcotic Antitussives by suppressing
the brain but have fewer adverse reactions. Nonnarcotic
Antitussives, such as Benzonatate, act locally to numb receptor
sites in the respiratory tract wall so cough messages cannot be
sent to the brain. Many of these medications are used in
combination and may occur in either prescription or
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Respiratory Smooth Muscle Relaxants
Smooth Muscle Relaxants are used to open air passageways and
limit such symptoms as shortness of breath, coughing, or
wheezing that are often associated with Allergies, Infections,
Asthma, Pneumonia, or Emphysema.
breathing is a two way process consisting of inspiration and
expiration. Air, containing gasses like oxygen, is transported
into the body during inspiration. Carbon dioxide gas is
transported out of the body during expiration. The nose, throat
and tracheobronchial tree move air to and from the lungs where
gas exchange occurs between the alveoli of the lungs and the
blood. The blood then circulates oxygen to cells to use as
energy. Carbon dioxide is released back into the blood stream,
carried to the alveoli, then released back into the air.
The respiratory centre of the brain regulates movement of the
respiratory muscles and walls of the bronchi leading to the
lungs. Nerves transmit impulses from the brain to constrict the
muscles and bronchial walls so less air is able to enter into
the body for gas exchange. Normally, the respiratory muscles are
flexible and respond to a feedback system by dilating when
carbon dioxide accumulates.
Certain disease processes of the upper and lower respiratory
tract decrease the flexibility of the respiratory muscles and
result in restricted gas exchange between the alveoli of the
lung and the blood stream. Inflammation of the tracheobronchial
tree, due to allergy or infection, causes increased mucus
production and swelling. The upper air passageways become
restricted due to this mucus and swelling and air movement is
hampered. This occurs in hay fever, common cold, tracheitis, or
bronchitis.. Pneumonia, Asthma, and Emphysema are diseases that
decrease the flexibility of the lower passageways due to
inflammation, making it difficult for the gas exchange between
the alveoli and the blood stream to occur. Constriction or
decreased flexibility of the respiratory muscles can cause
shortness of breath, coughing, wheezing or other symptoms.
Respiratory Smooth Muscle Relaxants, such as Xanthines,, convert
to theophylline that inhibits an enzyme (phosphodiesterase) to
directly relax smooth muscles of the respiratory tract and alter
the respiratory centre in the brain. With relaxation, breathing
passages open so air can be transported and effective gas
exchange can occur. If constriction due to muscle wall swelling
occurs, Xanthines are combined with Expectorants, Decongestants,
Antihistamines, or other medications to allow unrestricted gas
exchange and adequate oxygenation.
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Serums, Toxoids, & Vaccines
Serums, Toxoids, & Vaccines
provide immunity against Measles, Mumps, Rubella, Tetanus,
Hepatitis, and others. In contrast, other drugs may be given to
delay immunity and prevent Organ Rejection.
Pathogens, such as
bacteria and viruses, frequently attack the body. Typically,
pathogens enter the body and release toxins to invade and
destroy other cells. The normal body response is to destroy and
eliminate the pathogens or the cells they occupy.
When normal body defense systems cannot eliminate the pathogens,
they multiply and continue to release toxins, damaging normal
body cells. This can result in infectious disease, producing
minor symptoms such as fever, fatigue, body aches, or more
severe symptoms. In response, the body usually produces
antibodies to resist future invasion by that specific virus or
bacteria. The body can also react by producing substances
against other foreign tissue like transplanted organs. This is
called Organ rejection.
SERUMS, TOXOIDS, AND VACCINES artificially protect the body
against diseases caused by specific pathogens. Toxoids, such as
MMR or Tetanus Toxoid, contain altered bacteria and are given to
fight off invasion by bacterial toxic substances and prevent
harmful effects. Vaccines are altered viruses that are given to
fight off specific viral infections, such as Hepatitis B or
Typhoid Fever. Toxoids and Vaccines take time to be effective
against the pathogen but last for a long time. Serums are given
to establish immediate protection against disease but are short
acting. They are made from blood of humans or animals that have
recovered from the disease. In contrast, Immunosuppressants,
like Imuran or Sandimmune, prevent the immune response to
control organ rejection and other diseases.
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Skin & Mucous Membrane Agents
Skin & Mucous Membrane Agents and
Enzymes are applied directly to the skin or mucous membranes to
treat conditions such as Dry or Oily Skin, Dandruff, Acne,
Psoriasis, or even some Respiratory conditions (Asthma or Cystic
The largest organ in
the human body is the skin that covers and protects the body.
Components of the skin include the epidermis and the dermis. The
epidermis constantly regenerates and replaces cells, while the
dermis is composed of stretchable connective tissues, blood
vessels, nerves, and glands. The skin functions as a covering
and protects the organs and tissues within the body. Skin also
helps regulate temperature, excretes water, and serves as a
touch sense receptor. Mucous membranes, such as those in the
nose or throat, are epithelial cells that line body cavities
with exterior openings and frequently secrete mucus.
Disorders can occur due to alterations in the continuous skin
and mucous membrane coverings or glands within the skin. They
include Acne, psoriasis, dry or oily skin, and dandruff. Acne
occurs when the oil secreting sebaceous glands over produce and
plug hair follicles. Psoriasis occurs when new cell production
is greater than the sloughing of old cells causing an
accumulation and inflamed patchy area. Dandruff is the
accumulation of dead cells on the scalp forming scales that are
shed. Additionally, cavities coated with mucous membranes can
produce mucus plugs.
SKIN AND MUCOUS MEMBRANE AGENTS and ENZYMES act on the surface
of the skin and mucous membranes. They lubricate or remove
excess oil, encourage skin cell multiplication or loosen and
remove old cells, and protect the skin from sun, fade dark
spots, or restore colour.
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Vitamins & Caloric Agents
Caloric Agents are used in the prevention and treatment of
Malnutrition or Vitamin Deficiency.
A balanced intake of
food is needed to provide vitamins and nutrients. Food is then
digested, absorbed, and circulated as glucose or other chemicals
to all cells of the body to use for energy, growth, and repair.
Because nutrients cannot be adequately stored, frequent
replenishment is necessary to meet cell needs.
With inadequate nutritional intake, malabsorption, or other
illnesses, malnutrition and vitamin deficiency occur, resulting
in various states of disease. This can cause impaired growth and
impaired healing, as well as numerous cellular changes.
VITAMINS and Caloric Agents provide the nutrients absent from
daily consumption to maintain normal metabolic function, growth,
and repair. They also treat diseases caused by impaired daily
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