"Why do I experience low-grade fever in the afternoon but feel fine in the morning and evening?"

Low-Grade Fever: Clinical Definition and Potential Causes

Low-grade fever, clinically referred to as hypopyrexia, refers to a slightly elevated body temperature. The occurrence of low-grade fever exclusively in the afternoon, with no issues in the morning or evening, could stem from various factors such as environmental influence, dysautonomia, or pulmonary tuberculosis. It is recommended that patients consult with their healthcare providers to identify the underlying cause and choose appropriate daily care or medication. Detailed explanations are as follows:

1. Environmental Influence

If the patient's environment experiences lower temperatures in the morning and evening and higher temperatures in the afternoon, this may lead to a physiological rise in body temperature. This is a normal physiological phenomenon and usually does not require special treatment. However, one can adjust clothing according to the temperature changes.

2. Dysautonomia

Dysautonomia disrupts the balance of the temperature regulation center in the brain, resulting in abnormal body temperature fluctuations. Patients should cultivate healthy dietary habits, reduce stress and stimulation, and maintain a positive mindset, which can help alleviate symptoms.

3. Pulmonary Tuberculosis

When the lungs are infected by Mycobacterium tuberculosis, it can lead to pulmonary tuberculosis, which causes changes in body temperature, manifesting as low-grade fever in the afternoon. Accompanying symptoms may include cough and physical weakness. Medications such as Rifampicin, Ethambutol, and Isoniazid can be prescribed to eliminate the tuberculosis bacteria.

In addition to the above common causes, low-grade fever in the afternoon could also be attributed to connective tissue diseases. If symptoms persist without improvement, it is advised that patients seek prompt medical attention for further evaluation.