How Should Fever Be Treated?

The body’s heat mechanism, set-point, and the right approach

The weather has become colder and we’ve entered a period where viruses and microbes are more concentrated. That’s why almost everyone asks the same question: "Doctor, the fever has gone up—what should we do?" Right after this, questions usually follow about whether tests are needed, which medications should be used, and whether the fever is dangerous.

When families cannot reach a physician, they often rush to the pharmacy relying on information from the internet, and try to reduce the fever immediately with medications such as paracetamol or ibuprofen. However, intervening reflexively without understanding fever can work against the body’s own defense mechanism.

Fever is a system that keeps the body stable at 37°C. The hypothalamus in the brain functions like a thermostat and continuously adjusts the body to stay around 37°C. This temperature is essential for enzymes and hormones to function properly—an ideal "golden" value.

When body temperature drops, the system slows; when it rises too much, it begins to deteriorate. So why does temperature rise? The reason is not the microbes themselves, but the body’s defensive reaction against them.

When microbes release toxins into the bloodstream, pyrogenic substances within the immune system travel to the hypothalamus and raise the set-point from 37°C to 39°C. At this point, the brain sends the signal "I’m cold." As a result, muscles begin to contract, blood vessels constrict, thyroid hormones are activated, and the body starts generating heat.

For this reason, fever up to 39°C should be monitored carefully. Giving medication immediately, placing a child under a cold shower, or wiping the body with alcohol or vinegar may backfire. Because the surface vessels constrict, internal body temperature may rise even more.

When fever exceeds 39°C, two groups of medications are used. The first is paracetamol derivatives. These do not lower the fever directly; instead, they reset the set-point in the hypothalamus back to 37°C. The body then lowers the fever through its own mechanisms. The second group is non-steroidal anti-inflammatory drugs (NSAIDs), which provide both fever-reducing and anti-inflammatory effects.

If fever is the only symptom, paracetamol is usually preferred; if throat, ear, tooth, or other inflammatory pains are present, NSAIDs may be more appropriate. In some cases, the two can be alternated—but this must be done under medical supervision.

Excessive use of paracetamol can be toxic to the liver; high doses of NSAIDs can cause stomach or kidney bleeding. Not giving any medication, on the other hand, increases the risk of seizures when fever exceeds 40°C.

Therefore, the correct approach in fever management is to monitor up to 39°C carefully, and when it exceeds 39°C, follow your physician’s guidance regarding appropriate medication. Understanding that fever is the body’s own method of fighting microbes, and avoiding uncontrolled medication use, are the most important principles.