The Physiological Processes of Fever – Our Body’s Response and Personal Characteristics

Fever, also known as pyrexia, is a disturbance in the body’s temperature regulation, characterized by an increase in the body’s normal temperature. This phenomenon can be caused by various pyrogenic substances, and the degree of fever often exceeds daily physiological variations. Most people have experienced fever at some point, but many are unaware of what happens in their bodies during this time.

The Process of Temperature Regulation

The hypothalamus, located in the brain, is responsible for maintaining the body’s temperature. This center continuously monitors the body’s temperature and gathers various information from the heat sensors in the skin and internal organs. The process of temperature regulation is extremely complex, as it is influenced not only by the external environmental temperature but also by internal metabolic processes.

When the external temperature decreases, the skin’s heat receptors signal the hypothalamus, which induces vasoconstriction. This helps raise the body’s temperature, as blood flow to the skin decreases, resulting in less heat escaping from the body. Alongside these processes, muscle movement also increases, which generates heat. In particular, newborns have brown adipose tissue, which can efficiently produce heat through chemical reactions without the need for shivering.

In contrast, in a warm environment, heat loss becomes a priority for the body. The hypothalamus activates the skin’s warm receptors, which increase sweating and blood circulation, thereby aiding heat dissipation. Metabolic processes also accelerate, allowing the body to adapt to the warm environment.

The Biological Background of Fever

There are numerous causes for the development of fever, including infectious pathogens, immunological disorders, and conditions associated with cell breakdown. During fever, the body’s immune response is activated, during which various cells, such as monocytes and macrophages, engulf pathogens and release different internal pyrogenic substances known as cytokines.

These cytokines enter the bloodstream and reach the hypothalamus, where they reset the temperature regulation center, causing the body’s temperature to rise. In the initial phase of fever, the body temperature suddenly increases, accompanied by chills. The skin is cool and dry at this time, while metabolism accelerates.

In the next phase of fever, after reaching the new set-point, heat production and heat loss come into balance. The skin then becomes red and hot. Finally, when the fever subsides, the body returns to its normal state, during which heat dissipation increases, and body temperature normalizes.

Although fever often decreases without medication, internal hormone-like substances known as cryogens play a role in normalizing temperature.

Individual Differences in Fever Susceptibility

The susceptibility to fever can vary among individuals, arising from differences in the body’s temperature regulation mechanisms and internal pyrogenic substances. Some people easily develop fever, while others exhibit milder reactions, such as only a slight increase in temperature. This does not necessarily mean that individuals with lower fevers have weaker immune systems; in many cases, the immune response activates more quickly even without fever.

Experts believe that experiencing febrile states during childhood can be beneficial, as it may help prevent later allergies and autoimmune diseases. If children undergo febrile infections multiple times, it may help reduce the occurrence of allergies later in life.

Fever assists the body in overcoming infections and diseases, playing an important role in the healing process. The medical community increasingly recognizes the beneficial effects of fever in the body’s defense mechanisms.

The Effects of Fever on Well-being

During fever, the body undergoes numerous physiological changes that also affect overall well-being. Fever increases heart rate and respiratory rate, as well as metabolism. This process is accompanied by the activation of defensive immune mechanisms, which can cause muscle pain, increased sleepiness, and fatigue.

While fever can be beneficial for recovery, very high fever can decrease immune function, especially in children. In adults, hallucinations may occur, and the worsening of fever can lead to fainting, particularly in chronic patients. Thus, fever not only aids recovery but can also be dangerous in certain cases.

The ability to tolerate fever can also vary, and not everyone reacts in the same way. Therefore, it is important to consider the patient’s well-being and condition, alongside temperature, during fever reduction. In older age, especially when taking certain medications, disturbances in temperature regulation can develop, making fever potentially more problematic.

When fever presents itself, it is always advisable to consult a doctor to determine the most appropriate treatment method and further steps.