- 37° C is the normal body temperature.
- An extreme rise in body temperature may be damaging.
- Pyrogens are substances that cause a fever.
The normal body temperature of a human being is 37° C. However, it may change throughout the day due to several factors. When the body’s temperature is elevated, it is described as a fever. Unlike the standard body temperature, a fever is not a constant temperature. In some instances, intermittent fever occurs. This is when the temperature reaches to its peak level and then returns to normal.
An adult with raised body temperature will be hot to the touch with dry skin, parched lips, and watery eyes. Usually the body will be dehydrated. A person can get a fever in the case of extreme fatigue, if he is in the sun for long, or if he has any infections. Any inflammation in the body, including allergic reaction to drugs, can cause the body temperature to rise. Severe sweating and shivering, headaches, raised temperatures, and extreme weakness should not be ignored. These symptoms should be shared with the doctor for him to ascertain the reasons behind these and start on the treatment.
The symptoms of fever may depend mainly on the factors that cause the fever, rather than on the fever itself. A fever is considered to be the natural phenomenon the body displays when it is fighting against a condition. The human body has resistance up to a certain level. Once this level has been surpassed, the person can start feeling feverish.
The usual temporary rise in body temperature that is caused by most acute illnesses is very well tolerated by a healthy adult. However, a moderate fever can be slightly dangerous for an adult with a lung or heart disease, because the fever could cause an increase in the heart rate and breathing. In addition, a fever can aggravate the mental status of people who suffer from dementia.
An extreme rise in body temperature may be damaging for a person. A very high body temperature can result in malfunction and organ failure. This may be caused by severe infections, such as malaria, meningitis, or sepsis. Heatstroke or the use of certain drugs, such as amphetamines, cocaine, antipsychotic drugs, and anesthetics, are a couple other factors that contribute toward fever.
Causes of Fever in Adults
Pyroxenes are substances that cause a fever. These substances can enter internally or externally. Examples of pyrogens from outside the body are microorganisms and toxins, while the pyrogens formed in the body are produced by macrophages and monocytes. The pyrogens that enter from outside cause fever by exciting the body to discharge its own pyrogens. However, infection is not the sole cause of fever. A fever can also be caused by inflammation, an allergic reaction, a drug reaction, an autoimmune disorder, or an undetected cancer.
Since fever can be caused by several disorders, they are categorized into the following:
Infectious fever is the most common type of fever in adults that could last up to four days. On the other hand, a non-infectious fever could recur or last for a long time. Inflammatory conditions, such as rheumatoid arthritis, giant cell arteritis, and systemic lupus erythematosus, can have symptoms that include fever. Many cancers could cause fevers, too.
A person having a cold and cough might get fever. This is, again, the body’s way of fighting the virus. However, if the fever is very high and accompanied by a frequent feeling of extreme hot and cold, drowsiness, and weakness, then there will certainly be an underlying infection. Treatment with antibiotics will be started for at least 5 days until the temperature comes down and the symptoms are relieved. Diet will also be prescribed by the doctor, depending on the severity. Semi-solids in small portions and a fluid diet will be advised.
In healthy adults, acute fever is unlikely to be the first indication of a chronic condition.
In general, all infectious diseases cause fever, and the most likely causes include:
- Urinary tract infections
- Respiratory tract (upper and lower) infections
- Skin infections
- Gastrointestinal infections
Most of the gastrointestinal and respiratory tract infections are caused by viruses.
An individual’s age, health status, use of certain drugs, medical procedures, and certain occupations are some factors that may have an impact on fever.
Below are some warning signs of acute fever:
- Headache or stiff neck
- Change in mental function (confusion)
- Low blood pressure
- Dyspnea or shortness of breath
- Rapid breathing
- Rapid heart rate
- Petechiae (small, flat, purplish red spots on the skin)
When To See A Doctor
People who experience any of the warning signs mentioned above must consult a doctor immediately.
Additionally, people who have low-grade fevers that last more than about four to seven days may need investigation by a doctor while the fever (low-, intermediate-, or high-grade) persists. Some people may always need investigation and corresponding treatment. There can be chronic fevers, too. Diagnosis will be taken up by the doctor and medications prescribed immediately. Sometimes, hospitalization is needed to conduct more tests for a proper diagnosis. Early treatment can relieve the symptoms and bring comfort to the patient, but delays in diagnosis can lead to death, too.
The temperature is checked by a thermometer; the latest thermometers are digital, but a strip may also be used. After other symptoms are checked, the medical history will also be taken, as well as statistics like height, weight, and blood pressure. A doctor will also check the pulse, heartbeat, and the lungs for unusual murmurs. Once the diagnosis is done, medicines will be prescribed, along with a follow-up visit in case of need.
A doctor's advice should be sought if the fever lasts for more than 1 to 2 days, regardless of not showing any warning signs. If the fever continues for more than 3 to 4 days despite having other symptoms, seeking medical help is a must. Depending on the individual’s age, known medical conditions, and other symptoms, the doctor may recommend further evaluation or home treatment.
In case of patients having chronic health conditions such as diabetes, blood pressure, or heart disease, an underlying fever can be dangerous if not treated early. Meningitis, too, is a dangerous condition which can sometimes affect the brain. Symptoms of the flu with extreme headache and neck pain may be seen, but if diagnosed as a common flu with cold and not treated with correct medication, it can lead to death. Hence, the root cause behind an adult with fever needs to be checked and treated properly.