Everything you need to know about fever

Often considered a negative manifestation, fever is, instead, a defense mechanism of the organism that, within certain limits, can be useful. Let’s see when and how to fight it.

Often considered a negative manifestation, fever is, instead, a defense mechanism of the organism that, within certain limits, can be useful because it promotes healing from the illness that caused it. Let’s see when and how to fight it and what are the most useful remedies to lower body temperature.

What is fever

Fever is a transient increase in body temperature beyond the limit considered “normal” and which corresponds to 37.5 ° C, when measuring the temperature at the axillary level, and 38.0 ° C, when measuring it rectally.This rise represents a defense mechanism of the organism which, in itself, can slow down or block the multiplication of some pathogenic microorganisms (bacteria, viruses) sensitive to temperature, responsible for example for flu, otitis or respiratory tract infection, such as a severe cold, bronchitis or pneumonia.

The same applies in the case of other infections, such as:

• gastroenteritis, which also cause diarrhea, abdominal cramps, nausea, vomiting
• gingival or skin abscesses
• blood infections (septicemia).

Given its generic character, fever recognizes numerous possible origins that will have to be properly taken into account.

How to orient the doctor

Noting the progress of the fever and reconstructing what was done in the days before its appearance (possible contact with other sick individuals, exposure to cold, physical stress and so on) is a valuable aid for the doctor, who will be facilitated in identifying the possible causes.

Even the maximum value reached by fever can be an indirect expression of its origin: some diseases, such as bacterial infections of the respiratory tract (for example pharyngitis and tonsillitis associated or not with cough), determine significant increases in temperature, while viral ones tend to be associated with lower fever values (albeit with a certain variability in relation to the particular virus involved and the reaction individual immunity).

Obviously, as obvious and trivial as it may seem, to correctly measure the fever it is advisable to use a reliable thermometer: in the case of children, the guidelines recommend a digital instrument to be inserted under the armpit for a few tens of seconds, until the audible alarm warns that the measurement is completed.

To avoid errors of assessment, it is important to always use the same measurement technique and know the body temperature of the person under normal conditions, bearing in mind that everyone has a different basal temperature value and that, with advancing years, body temperature tends physiologically to decrease.

It should be remembered, then, that there are situations such as, for example, a dental eruption, a vaccination, the practice of intense physical exercise (especially if associated with a lively competitive sense) that can induce a modest and temporary rise in body temperature, completely benign and, generally, not worthy of treatment.

That very typical course

The trend of fever is, in general, quite typical. Initially, chills, exhaustion and general malaise appear: this is the moment when the body feels a strong sensation of cold and tries to increase the production of heat, causing the temperature to rise.

Once its maximum value is reached, the body temperature tends to settle and remain elevated for an interval of time ranging from a few hours to a few days (if not treated with antipyretic), to be reduced later.

This third and final phase is called “defervescence” and is characterized by the feeling of excessive heat and the production of sweat, aimed at bringing body temperature back to normal value.

Generally, during the “defervescence” phase we tend to discover ourselves to favor the dispersion of body heat, even through the evaporation of sweat. At this time, especially if it is a child, keeping too many clothes on and remaining excessively covered is wrong because it counteracts the mechanism of spontaneous “fevering”.

The ideal is to wear light clothing, which absorbs sweat well, and cover the bare minimum so as not to catch cold. Another important recommendation is to drink plenty of water or other liquids (at least 2 liters a day) to compensate for those lost through sweat and ensure good hydration to the body. Preventing dehydration is particularly important if, in addition to fever, there are also vomiting and / or diarrhea, which cause a considerable loss of fluids and mineral salts.

After the “defervescence” phase, in general, the body temperature returns to normal in a stable and lasting way.

An exception to this rule is the “intermittent fever”, a fever with an atypical course characterized by large fluctuations in body temperature, within the same day or on different days, with periods of total absence of fever and others of very high fever.

Myths to debunk and mistakes to avoid

In the collective imagination, there are still some beliefs about fever that must be debunked. Here are the most common.

Some special situations

Fever is not always synonymous with infection: there may, in fact, be some situations in which the rise in body temperature must be considered in a different perspective from the traditional one. Here are some examples.

• After a vaccination, any increase in temperature, usually modest, expresses the normal reaction of the body to immune stimulation and, in general, does not even require specific treatment.
• The increase in body temperature can be favored by particular emotional conditions (stress, anxiety) or excessive exposure to the sun.
• In autoimmune diseases (rheumatoid arthritis, lupus erythematosus, scleroderma) fever expresses the aggression of the organism against itself and sometimes is accompanied by another important symptom: pain.
• An intense and acute allergic reaction, a minor surgical or dental intervention or an accidental trauma are other cases in which fever may occur, in the context of the inflammatory response to the affected tissues / organs.

Practical tips

Some tips on how to manage fever have already been mentioned, but it is good to summarize the general indications.

• In addition to the temperature value, when choosing whether or not to treat fever, its impact on the well-being of the person concerned and the possible simultaneous presence of other symptoms must be carefully considered. Remember that a high fever endured well requires a less aggressive approach than a less significant, but very annoying fever.
• Pay particular attention to extreme age groups (young children and the elderly), in which fever can be more challenging for the body, and to temperature rises in pregnancy.
• In the elderly, the intake of anti-inflammatory / antipyretic drugs should always be indicated by the doctor because there may be other pathologies that contraindicate the intake of certain active ingredients (heart failure, high blood pressure and other cardiovascular diseases, gastric ulcer, gastrointestinal reflux, etc.).
• To lower body temperature and relieve general malaise, it is not recommended to use any “physical” means, such as ice packs or sponges with cold water, instead of or in association with antipyretic.
• During a febrile episode the appetite often subsides. It is not necessary to force yourself to eat if you are not hungry, but it is very important to drink, because they increase the body’s water losses. Nutrition should favor simple and digestible foods and, in case of infection, sources of vitamins, such as fruit. To replenish the liquids lost through sweat, in addition to drinking water, you can take chicken broth (endowed, it is said, with antiviral activity) or vegetables, citrus juices (rich in vitamin C and other antioxidants), chamomile or light tea with a little lemon, thyme-based herbal teas, lime (with a calming effect on the airways) or elderberry (which increases sweating, favoring fever), sweetened with a teaspoon of honey or “strengthened” by a little ginger (with antioxidant and anti-inflammatory properties). The latter can also be used in the form of essential oils.
• Unless in special situations, it is correct to deal with fever with common self-medication remedies. If after 2-3 days the body temperature remains above normal, it is good to contact the doctor, to whose attention a possible fever must also be subjected that recurs regularly every day, even in the absence of other disorders.
• Medications, including self-medication, should be used responsibly, paying attention to those that contain several different active ingredients and consulting your doctor in advance if you are also taking other medicines. There is, in fact, the risk of unfavorable interactions between drugs, which can give rise to unpleasant and sometimes even serious side effects (for example, increased activity of an anticoagulant, damage to the stomach mucosa, toxic effects on the liver or renal system).