SYMPTOMATIC TREATMENT OF FEVER

1. SYMPTOMATIC TREATMENT OF FEVER

2. A fever is any body temperature elevation over100°F (37.8°C). A healthy person’s body temperature fluctuatesbetween 97°F (36.1°C) and 100°F (37.8°C), with theaverage being 98.6°F (37°C). The body maintains stabilitywithin this range by balancing the heat produced by themetabolism with the heat lost to the environment. The“thermostat” that controls this process is located in thehypothalamus, a small structure located deep within thebrain. The nervous system constantly relays informationabout the body’s temperature to the thermostat, which inturn activates different physical responses designed tocool or warm the body, depending on the circumstances.

3. Temperature • Body temperature is not constant all day, butactually is lowest at 6 A.M. and highest around 4–6 P.M. Inaddition, temperature varies in different regions of thebody; for example, rectal and urine temperatures areabout one degree Fahrenheit higher than oral temperatureand rectal temperature is higher than urine. It is alsoimportant to realize that certain normal conditions caneffect body temperature, such as pregnancy, food ingestion, age, and certain hormonal changes.

4. Substances that cause fever are known as “pyrogens.” • Two types of pyrogens; exogenous andendogenous. • Those that originate outside the body, suchas bacterial toxins, are called “exogenous” pyrogens. • Pyrogens formed by the body’s own cells in response toan outside stimulus (such as a bacterial toxin) are called“endogenous” pyrogens (prostaglandins).

5. FEVER A fever occurs when the thermostat resets at a highertemperature, primarily in response to an infection. Toreach the higher temperature, the body moves blood tothe warmer interior, increases the metabolic rate, andinduces shivering. The “chills” that often accompany afever are caused by the movement of blood to the body’score, leaving the surface and extremities cold. Once thehigher temperature is achieved, the shivering and chillsstop.

6. FEVER When the infection has been overcome or drugssuch as aspirinor acetaminophen(Tylenol) have beentaken, the thermostat resets to normal and the body’scooling mechanisms switch on: the blood moves to thesurface and sweating occurs.

7. A dramatic rise in body temperature often includes the following symptoms: A. Loss of fluid results in dehydration. B.Thehypothalamic set-point is increased, raising metabolism. C. Blood vessels in skin dilate. D. Sweat glands produce excessperspiration. E. Increased pulse rate. F. Increased hypothalmic set-point may introduce chills and shivering to promote heatproduction from muscles. G. Skin becomes more heat-sensitive

8. An elevated body temperature hasseveral effects: • The immune system chemicals increase the production of cells thatfight off the invading bacteria or viruses. • Higher temperaturesalso inhibit the growth of some bacteria, • Theincreased heart rate that may accompany the changes inblood circulation also speeds the arrival of white bloodcells to the sites of infection

9. Causes and symptoms • Fevers are primarily caused by viral or bacterialinfections, such as pneumoniaor 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.

10. Causes and symptoms (cont’d) • Malignant hyperthermia is a rare, inheritedcondition in which a person develops avery highfever when given certain anesthetics or muscle relaxantsin preparation for surgery.

11. Causes and symptoms (cont’d) • Most feverscaused by infections are acute, appearing suddenly andthen dissipating as the immune system defeats the infectiousagent. • An infectious fever may also rise and fallthroughout the day, reaching its peek in the late afternoonor early evening. • A low-grade fever that lasts forseveral weeks is associated with autoimmune diseasessuch as lupus or with some cancers, particularlyleukemia and lymphoma.

12. Fever. Causes in kids • Infections (bacterial, viral, fungal) • Overheating • Stress • Toothing • Allergic reactions • Water-electrolite dysbalance • Vaccinations

13. "Threatenings" symptoms • A fever requires emergency treatment under the followingcircumstances: • newborn (three months or younger) with a fever over100.5°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

14. Threatening symptoms (cont’d) • A very high fever in a small child can triggerseizures (febrile seizures) and therefore should be treatedimmediately. • A fever accompanied by the above symptomscan indicate the presence of a serious infection,such as meningitis, and should be brought to the immediateattention of a physician. • A feverover100.5°F (38°C) 3 days and longer • A feverover37,5°C 2 weeks and longer

15. Fever of unknown origin (FUO) • When temperature elevation occurs for an extendedperiod of time and no cause is found, the term FUO isthen used. The far majority of these patients are eventuallyfound to have one of several diseases: • Tuberculosisremains an important cause, especiallywhen it occurs outside the lungs. • Allergiesto medications can also cause prolongedfever(sometimes patients will have other symptoms suggestingan 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).

16. Diagnosis • A fever is usually diagnosed using a thermometer (orally, rectally, by placing a thermometerunder the armpit) • Blood tests can aid in identifying an infectious agent, white bloodcell counts • Ultrasound tests, magnetic resonance imaging (MRI) tests, or computed tomography (CT) scans may be ordered if the doctor cannot readily determine thecause of a fever.

17. Treatment • Drugs to lowerfever (antipyretics) can be given if a patient (particularlya child) is uncomfortable. • These include aspirin, acetaminophen(Tylenol), and ibuprofen (Advil). • Aspirin should not be given to a child or adolescentwith a fever since this drug has been linked to anincreased risk of Reye’s syndrome(A disorder principally affectingthe liver and brain, marked by the rapid developmentof life-threatening neurological symptoms) • Bathing a patient incool water can also help alleviate a high fever.

18. Treatment (cont’d)Antipyretic • Aspirinis the prototype of the analgesic–antipyretic–anti-inflammatory drugs and the most commonly used salicylate. • It is effectivein 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.

19. Treatment (cont’d)Antipyretic • Regular aspirin tablets are well absorbed after oral administration;their action starts within 15 to 30 minutes, peaksin 1 to 2 hours, and lasts 4 to 6 hours. Taking aspirin withfood slows absorption, but also decreases gastric irritation. • Absorption of enteric-coated aspirin and rectal suppositoriesis slower and less complete.

20. Treatment (cont’d)Antipyretic • Aspirin is distributed to all body tissues and fluids, includingfetal tissues, breast milk, and the central nervoussystem (CNS). • Aspirin is a home remedy for headaches, colds, influenzaand other respiratory infections, muscular aches, and fever. • Itcan be purchased in plain, chewable, enteric-coated, and effervescenttablets and rectal suppositories. • It is not marketedin liquid form because it is unstable in solution.

22. Treatment (cont’d) Propionic acid derivatives • ibuprofen (Motrin, Advil), ketoprofen(Orudis), naproxen (Naprosyn) • are available OTC • these drugs are usually better toleratedthan aspirin, they are much more expensive and maycause all the adverse effects associated with aspirin and otherprostaglandin inhibitors

23. Ibuprofen Ibuprofen, a commonly used drug, is well absorbed withoral administration. Its action starts in about 30 minutes,peaks in 1 to 2 hours, and lasts 4 to 6 hours. The drug is highlybound (about 99%) to plasma proteins and has a half-life ofabout 2 hours. It is metabolized in the liver and excretedthrough the kidneys. It is available by prescription and OTC,in tablets, chewable tablets, capsules, oral suspension, andoral drops, for use by adults and children.

24. Acetaminophen • is a nonprescription drug commonlyused as an aspirin substitute because it does not causenausea, vomiting, or GI bleeding, and it does not interferewith blood clotting. • It is equal to aspirin in analgesic andantipyretic effects, but it lacks anti-inflammatory activity. • Acetaminophen is well absorbed with oral administrationand peak plasma concentrations are reached within 30to 120 minutes. Duration of action is 3 to 4 hours.

25. Acetaminophen • Acetaminophen is available in tablet, liquid, and rectalsuppository forms and is in numerous combination productsmarketed as analgesics and cold remedies. It is often prescribedwith codeine, hydrocodone, or oxycodone for addedanalgesic effects.

27. Treatment (cont’d) Acetaminophen can cause liver damage; ibuprofen is a relativeof aspirin that can cause gastrointestinal upset andbleeding. Total daily dosage should not be excessive (with Tylenol, above four doses of 1000mg each; with ibuprofen, above 2400 mg).

28. Treatment (cont’d) Dipyrone (metamizole) • displays the highestefficacy among antipyretic analgesics. • It is rapidly absorbedwhen given via the oral or rectal route.Because of its water solubility, it is alsoavailable for injection. • Dipyrone is associated with a low incidenceof fatal agranulocytosis. In sensitizedsubjects, cardiovascular collapsecan occur, especially after intravenousinjection. • The drug should berestricted to the management of painrefractory to other analgesics

29. 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:

30. 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 Alka-Seltzer 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.

31. 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.

32. 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.

33. 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) dueto inhibition of PGE2 synthesis and overproductionof 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.