Introduction
According to the medical definition, fever is an increase in body temperature to over 38° Celsius. Fever is an adjustment of the target value of the body core temperature: Whenever the brain wants to raise the temperature, this information is transmitted from the brain stem to the nervous system of the entire body. Headaches often occur as an accompanying symptom together with fever.
In the case of headaches, it is not the brain substance itself that hurts, but the so-called meninges. This lies around the brain and contains not only nerve fluid, blood and lymph vessels, but also sensitive nerve cells, enabling the meninges to “perceive” pain stimuli. Such pain stimuli can then be triggered by the messenger substances released by the inflammation or the lack of fluid caused by the fever. Fever, which is caused by drugs or medication, can also often be accompanied by headaches.
Causes of fever and headaches
Both fever and headache are very unspecific symptoms (so-called “general symptoms”), which means that they can occur in a variety of different clinical pictures. The reason for the simultaneous occurrence of both symptoms is usually an inflammatory process in the body, triggered for example by a bacterial or viral infection. This is mainly due to the fact that the inflammatory reaction – as mentioned above – releases corresponding messenger substances which, among other things, cause vasodilation in the brain.
As a result, the brain substance swells slightly and the meninges are stretched and thus irritated. If the headaches occur after a fever episode that has already lasted for some time, the cause is usually a simple lack of fluid. If there is concrete suspicion of an infection, more attention should be paid to other symptoms that indicate the origin or location of the infection, such as abdominal pain or diarrhea (gastrointestinal infection), pain when urinating (urinary tract infection), cold symptoms or signs of meningitis.
Meningitis can be characterized by stiffness of the neck and the inability of the person to lift a leg or pull a knee towards the chest while supine. In addition to infection, fever and headache can also be caused by chemical substances such as drugs or medicines. In this case, it is advisable to look for clues as to the type and amount of the substance in order to enable appropriate and adequate treatment.
A cold or flu-like infection is a common cause of fever and headaches, but by no means the only one. First of all, a cold can just start, so that the typical symptoms are not yet noticeable. Other infections that are not located in the throat, nose or respiratory tract can also cause fever and headaches.
It is important to rule out meningitis as soon as possible, as it can cause long-term neurological damage if left untreated. Infections of the gastrointestinal or urinary tract can also cause corresponding symptoms. If no signs of infection can be found, an acute overdose of a medication or drug should be considered. Finally, hormonal imbalances can also cause fever and headaches.
