The afebrile state is characterized by an absence of fever. It is a term of medical “jargon” which may cause concern but is in fact often used by physicians to mean that the patient’s condition is improving.

The word “afebrile” is a medical term, derived from the Latin apyretus and the Greek puretos, which means fever. Used as an adjective, it describes the condition of a patient who has no or no longer has a fever.

Also, a disease is called apyretic when it manifests itself without fever.

In addition, a drug is qualified as “afebrile” in pharmacology to designate drugs that reduce fever (paracetamol, anti-inflammatory drugs). Apyrexia refers to the condition in which the afebrile patient is found. This state is by definition opposed to fever. In the case of recurrent fevers, the patient is said to alternate between febrile and afebrile phases.

Most often, fever is one of the symptoms suggestive of the infectious syndrome: fever, headache, body aches, sweating, chills, etc. It is said that someone is afebrile when he previously had a fever and it has gone down.

To understand apyrexia it is easier to look at its opposite: fever.

Fever is mainly caused by infections. Apyrexia is a sign of a return to normal; the infection is under control and on the mend. During antibiotic treatment, a return to apyrexia is expected within 2 to 3 days.

In some cases (immunosuppression, old age), you can have a real infection while remaining afebrile. You should know that the absence of fever is not always the sign of the absence of infection.

In some diseases, there is an alternation of fever and periods of apyrexia. It is the witness of a disease which is not cured but in which relapsing fever is a warning sign.

It is important not to claim victory too quickly and stop the treatments prescribed by the doctor. Indeed, when antibiotic treatment is effective, a rapid return to apyrexia is expected. But apyrexia is not synonymous with cure. The duration of antibiotic treatment has been defined and refined for decades to allow complete eradication of bacteria. Stopping treatment too early may promote resistance to antibiotics and recurrence of the infection. Therefore, even when the afebrile state appears again, antibiotics must be continued to completely eradicate the infection.

Some clinical cases have shown in modern times the appearance of recurrent or intermittent fevers. Their duration exceeds three weeks, and these fevers occur in repeated episodes, intermittent and relapsing, spaced by afebrile intervals. Thus, afebrile condition may mean that the patient is in the middle of an episode of intermittent fever, the diagnosis of which remains difficult. Usually, fevers that last more than three days for no apparent reason are said to be unexplained. After three weeks, we talk about prolonged unexplained fever. Intermittent fever (and the associated feverlessness) constitutes a special case of these fevers which are difficult to explain.

Medicines intended to lower fever (paracetamol, anti-inflammatory drugs) can be used if the fever is poorly tolerated, for example in the event of severe associated headaches.

Paracetamol, a so-called apyretic drug (fight against fever) should be used as a priority because of the few side effects it has. Be careful, however, to respect an interval of 6 hours between doses and not to take more than one gram per dose (ie 1000 milligrams).

Particular attention must also be paid to the risk of drugs containing paracetamol in combination with other molecules, which could lead to involuntary intake of paracetamol. This can lead to unintentional overdoses.

Do not worry that taking an antipyretic will mask the fever, because an active infection will give a fever regardless of the treatment taken.

The afebrile state in itself is not a sign of ill health, since it means no fever. However, when a patient is qualified as afebrile, this means that he must be attentive to how his condition evolves, since he usually comes out of a period of fever, continuous or intermittent. His infection is therefore possibly still present. It is advisable to be very careful, to continue to take its treatment, and in case of return of symptoms (headaches, pains, difficulties in breathing, or return of fever, etc.), do not hesitate to consult, in mentioning the various febrile episodes previously encountered.