In simple words: Postviral fatigue syndrome is a long-term condition causing constant tiredness that doesn't improve with rest and affects daily life. It often follows a viral infection. Symptoms include exhaustion, muscle aches, and difficulty concentrating. Doctors diagnose it based on symptoms and medical history, sometimes using blood tests to rule out other problems.While there's no cure, treatments can help manage symptoms.

Postviral fatigue syndrome, also known as chronic fatigue syndrome, describes fatigue or myalgia secondary to a prior persistent viral infection that differs from ordinary tiredness. It begins a day or two after physical, mental, or emotional exertion. Symptoms fluctuate in severity and duration. Patients experience unrelenting physical and mental exhaustion, malaise, muscle aches and pains (myalgias), and variable psychiatric symptoms such as labile emotions, poor memory, and concentration problems. Diagnosis is based on medical history, signs, symptoms, and physical examination. There are no specific diagnostic procedures, but blood and urine tests may be performed to rule out other conditions. There is no cure or specific treatment for the condition, but symptoms can sometimes be managed with medications and other therapies.

Example 1: A patient presents with persistent fatigue, muscle pain, and difficulty concentrating following a diagnosed viral infection several weeks prior. After ruling out other potential causes, the physician diagnoses postviral fatigue syndrome (G93.3)., A patient with a history of mononucleosis experiences ongoing fatigue, sleep disturbances, and cognitive impairment.These symptoms are consistent with postviral fatigue syndrome (G93.3)., A patient experiences severe fatigue, headaches, and joint pain after recovering from influenza.After extensive testing and evaluation, the diagnosis of postviral fatigue syndrome (G93.3) is made.

Documentation should include the following: detailed history of the viral infection, onset and duration of fatigue symptoms, impact on daily activities, associated symptoms like muscle pain or cognitive difficulties, and results of any tests performed to rule out other conditions.