Download SYMPTOMATIC TREATMENT OF FEVER

SYMPTOMATIC
TREATMENT OF FEVER
A fever is any body temperature
elevation over
100°F (37.8°C).
A healthy person’s body temperature
fluctuates between 97°F (36.1°C) and 100°F
(37.8°C), with the average being 98.6°F (37°C).
The body maintains stability within this range by
balancing the heat produced by the metabolism
with the heat lost to the environment. The
“thermostat” that controls this process is located
in the hypothalamus, a small structure located
deep within the brain. The nervous system
constantly relays information about the body’s
temperature to the thermostat, which in turn
activates different physical responses designed
to cool or warm the body, depending on the
circumstances.
Temperature
Body temperature is not constant all day,
but actually is lowest at 6 A.M. and highest
around 4–6 P.M. In addition, temperature
varies in different regions of the body; for
example, rectal and urine temperatures
are about one degree Fahrenheit higher
than oral temperature and rectal
temperature is higher than urine. It is also
important to realize that certain normal
conditions can effect body temperature,
such as pregnancy, food ingestion,
age, and certain hormonal changes.
Substances that cause fever are known as
“pyrogens.”
Two types of pyrogens; exogenous and
endogenous.
Those that originate outside the body, such as
bacterial toxins, are called “exogenous”
pyrogens.
Pyrogens formed by the body’s own cells in
response to an outside stimulus (such as a
bacterial toxin) are called “endogenous”
pyrogens (prostaglandins).
FEVER
A fever occurs when the thermostat resets at
a higher temperature, primarily in response to an
infection. To reach the higher temperature, the
body moves blood to the warmer interior,
increases the metabolic rate, and induces
shivering. The “chills” that often accompany a
fever are caused by the movement of blood to
the body’s core, leaving the surface and
extremities cold. Once the higher temperature is
achieved, the shivering and chills stop.
FEVER
When the infection has been overcome
or drugs such as aspirin or
acetaminophen (Tylenol) have been
taken, the thermostat resets to normal and
the body’s cooling mechanisms switch on:
the blood moves to the surface and
sweating occurs.
A dramatic rise in body temperature often includes the following
symptoms: A. Loss of fluid results in dehydration. B.The
hypothalamic set-point is increased, raising metabolism. C. Blood
vessels in skin dilate. D. Sweat glands produce excess
perspiration. E. Increased pulse rate. F. Increased hypothalmic setpoint may introduce chills and shivering to promote heat
production from muscles. G. Skin becomes more heat-sensitive
An elevated body temperature has
several effects:
The immune system chemicals increase
the production of cells that fight off the
invading bacteria or viruses.
Higher temperatures also inhibit the
growth of some bacteria,
The increased heart rate that may
accompany the changes in blood
circulation also speeds the arrival of white
blood cells to the sites of infection
Causes and symptoms
Fevers are primarily caused by viral or bacterial
infections, such as pneumonia or influenza.
Conditions that can induce a fever:
Allergic reactions;
autoimmune diseases;
trauma, such as breaking a bone;
cancer;
excessive exposure to the sun;
Intense exercise;
hormonal imbalances;
certain drugs;
damage to the hypothalamus.
Causes and symptoms (cont’d)
Malignant hyperthermia is a rare, inherited
condition in which a person develops a
very high fever when given certain
anesthetics or muscle relaxants in
preparation for surgery.
Causes and symptoms (cont’d)
Most fevers caused by infections are acute,
appearing suddenly and then dissipating as the
immune system defeats the infectiousagent.
An infectious fever may also rise and fall
throughout the day, reaching its peek in the late
afternoon or early evening.
A low-grade fever that lasts for several weeks is
associated with autoimmune diseases such as
lupus or with some cancers, particularly
leukemia and lymphoma.
Fever. Causes in kids
Infections (bacterial, viral, fungal)
Overheating
Stress
Toothing
Allergic reactions
Water-electrolite dysbalance
Vaccinations
"Threatenings" symptoms
A fever requires emergency treatment under the
following circumstances:
• newborn (three months or younger) with a fever
over 100.5°F (38°C)
• infant or child with a fever over 103°F (39.4°C)
• fever accompanied by severe headache, neck
stiffness, mental confusion, convulsions, or
severe swelling of the throat
Threatening symptoms (cont’d)
A very high fever in a small child can trigger
seizures (febrile seizures) and therefore should
be treated immediately.
A fever accompanied by the above symptoms
can indicate the presence of a serious infection,
such as meningitis, and should be brought to
the immediate attention of a physician.
A fever over 100.5°F (38°C) 3 days and longer
A fever over 37,5°C 2 weeks and longer
Fever of unknown origin (FUO)
– When temperature elevation occurs for an extended
period of time and no cause is found, the term FUO is
then used. The far majority of these patients are
eventually found to have one of several diseases:
– Tuberculosis remains an important cause, especially
when it occurs outside the lungs.
– Allergies to medications can also cause prolonged
fever (sometimes patients will have other symptoms
suggesting an allergic reaction, such as a rash).
– HIV is a potential cause of fever. (Patients with HIV
are an especially difficult problem, as they often suffer
from many unusual infections).
Diagnosis
A fever is usually diagnosed using a
thermometer (orally, rectally, by placing a
thermometer under the armpit)
Blood tests can aid in identifying an infectious
agent, white blood cell counts
Ultrasound tests, magnetic resonance imaging
(MRI) tests, or computed tomography (CT)
scans may be ordered if the doctor cannot
readily determine the cause of a fever.
Treatment
Drugs to lower fever (antipyretics) can be given
if a patient (particularly a child) is uncomfortable.
These include aspirin, acetaminophen (Tylenol),
and ibuprofen (Advil).
Aspirin should not be given to a child or
adolescent with a fever since this drug has been
linked to an increased risk of Reye’s syndrome
(A disorder principally affecting the liver and
brain, marked by the rapid development of lifethreatening neurological symptoms)
Bathing a patient in cool water can also help
alleviate a high fever.
Treatment (cont’d)
Antipyretic
Aspirin is the prototype of the analgesic–
antipyretic–anti-inflammatory drugs and the
most commonly used salicylate.
It is effective in pain of low to moderate
intensity, involving the skin, muscles, joints,
and other connective tissue.
It is useful in inflammatory disorders, such as
arthritis, but many people prefer drugs that
cause less gastric irritation.
Treatment (cont’d)
Antipyretic
Regular aspirin tablets are well absorbed
after oral administration; their action starts
within 15 to 30 minutes, peaks in 1 to 2
hours, and lasts 4 to 6 hours. Taking aspirin
with food slows absorption, but also
decreases gastric irritation.
Absorption of enteric-coated aspirin and
rectal suppositories is slower and less
complete.
Treatment (cont’d)
Antipyretic
Aspirin is distributed to all body tissues and
fluids, including fetal tissues, breast milk,
and the central nervous system (CNS).
Aspirin is a home remedy for headaches,
colds, influenza and other respiratory
infections, muscular aches, and fever.
It can be purchased in plain, chewable,
enteric-coated, and effervescent tablets and
rectal suppositories.
It is not marketed in liquid form because it is
unstable in solution.
Treatment (cont’d)
Propionic acid derivatives
ibuprofen (Motrin, Advil), ketoprofen
(Orudis), naproxen (Naprosyn)
are available OTC
these drugs are usually better tolerated
than aspirin, they are much more
expensive and may cause all the adverse
effects associated with aspirin and other
prostaglandin inhibitors
Ibuprofen
Ibuprofen, a commonly used drug, is well
absorbed with oral administration. Its action
starts in about 30 minutes, peaks in 1 to 2 hours,
and lasts 4 to 6 hours. The drug is highly bound
(about 99%) to plasma proteins and has a halflife of about 2 hours. It is metabolized in the liver
and excreted through the kidneys. It is available
by prescription and OTC, in tablets, chewable
tablets, capsules, oral suspension, and oral
drops, for use by adults and children.
Acetaminophen
is a nonprescription drug commonly used as an
aspirin substitute because it does not cause
nausea, vomiting, or GI bleeding, and it does not
interfere with blood clotting.
It is equal to aspirin in analgesic and antipyretic
effects, but it lacks anti-inflammatory activity.
Acetaminophen is well absorbed with oral
administration and peak plasma concentrations
are reached within 30 to 120 minutes. Duration
of action is 3 to 4 hours.
Acetaminophen
Acetaminophen is available in tablet,
liquid, and rectal suppository forms and is
in numerous combination products
marketed as analgesics and cold
remedies. It is often prescribed with
codeine, hydrocodone, or oxycodone for
added analgesic effects.
Treatment (cont’d)
Acetaminophen can cause liver damage;
ibuprofen is a relative of aspirin that can
cause gastrointestinal upset and bleeding.
Total daily dosage should not be excessive
(with Tylenol, above four doses of 1000
mg each; with ibuprofen, above 2400 mg).
Treatment (cont’d)
Dipyrone (metamizole)
displays the highest efficacy among antipyretic
analgesics.
It is rapidly absorbed when given via the oral or
rectal route. Because of its water solubility, it is
also available for injection.
Dipyrone is associated with a low incidence of
fatal agranulocytosis. In sensitized subjects,
cardiovascular collapse can occur, especially
after intravenous injection.
The drug should be restricted to the
management of pain refractory to other
analgesics
Treatment (cont’d)
Some OTC products contain an
analgesic/antipyretic as a single ingredient.
Others combine an analgesic/antipyretic with a
nasal decongestant, an antihistamine, or a
cough suppressant. Products listed in the
headaches, body aches, fever, and flu-like
symptoms category contain an
analgesic/antipyretic either alone or in
combination with other ingredient(s) to treat
cold/flu/allergy symptoms. Examples of products
in the headaches, body aches, fever, and flu-like
symptoms category include:
Treatment (cont’d)
Aspirin (plain aspirin, coated aspirin, or aspirin
mixed with antacid): Aspirin Regimen Bayer
Regular Strength, Extra Strength Bayer Plus
Caplets, Bufferin Analgesic Tablets, Regular
Strength Ascriptin, Ascriptin Enteric, and AlkaSeltzer Extra Strength.
Acetaminophen: Tylenol Regular Strength
Caplets and Tablets, Aspirin Free Excedrin
Analgesic Caplets and Geltabs, Children's
Tylenol Chewable Tablets, Elixir, and
Suspension Liquid, and Junior Strength Tylenol
Coated Caplets and Chewable Tablets.
Treatment (cont’d)
Analgesic/antipyretic
NSAIDs: Advil Caplets, Aleve Tablets and Caplets,
Motrin IB Pain Reliever Caplets and Gelcaps, and
Children's Motrin Drops.
Aspirin plus a decongestant and/or cough
suppressant: Alka-Seltzer Plus Cold and Cough.
Acetaminophen plus a decongestant and/or cough
suppressant: Tylenol Cold Medication Multi-Symptom
Caplets and Tablets, Theraflu Flu and Cold Medicine,
Actifed Cold and Sinus Caplets and Tablets, and
Children's Tylenol Flu Liquid.
NSAID plus a decongestant and/or cough
suppressant: Advil Cold and Sinus Caplets and Motrin
IB Sinus Caplets and Tablets.
The following guidelines are provided to help
consumers make more informed choices
when selecting OTC products:
Always read the labels and know the ingredients in the
products. Never take more than the recommended
dose.
Do not use aspirin-containing medicines for children
and teenagers with influenza, chickenpox or other viral
illnesses. Rare cases of Reye syndrome have been
associated with the use of aspirin in this population.
Reye syndrome is a serious illness characterized by
liver damage, vomiting, and sometimes coma. It has a
50% mortality rate, and those who survive can be left
with permanent brain damage.
Therefore, acetaminophen-containing products are
recommended for children with fever. NSAIDs may be
used in children over six months of age.
Guidelines
Aspirin and NSAIDs can cause ulcers and increase the
risk of bleeding, and should be avoided by people with
known ulcer disease or certain blood diseases. People
who are scheduled for elective surgeries should inform
their doctors that they are taking aspirin or NSAIDs.
A true aspirin allergy is rare. Aspirin allergy consists of
hives, occasionally difficulty breathing, and rarely shock,
within three hours of taking aspirin. Aspirin can precipitate
bronchoconstriction (“aspirin asthma,” pseudoallergy) due
to inhibition of PGE2 synthesis and overproduction of
leukotrienes. Aspirin allergy is most common among
individuals who have asthma, urticaria, and nasal polyps.
Individuals with aspirin allergy should also avoid NSAIDs
because they are chemically similar to aspirin.
Aspirin can cause complications during pregnancy and
should be avoided during pregnancy.
Aspirin can increase the effectiveness of blood thinning by
Coumadin and may increase the risk of bleeding.