Patient presents with persistent and unexplained fatigue (Other Fatigue, R53.83), impacting daily activities and quality of life.  Symptoms include generalized weakness, tiredness, exhaustion, and reduced physical and mental endurance.  Onset of fatigue is gradual and not relieved by rest.  Differential diagnosis includes chronic fatigue syndrome, fibromyalgia, depression, anemia, hypothyroidism, sleep disorders, and other medical conditions.  Comprehensive metabolic panel, complete blood count, thyroid stimulating hormone, and sleep study were ordered and results are pending or within normal limits, ruling out common organic causes.  Patient reports no history of substance abuse or significant psychosocial stressors.  Physical examination revealed no abnormalities.  Assessment indicates Other Fatigue, a diagnosis of exclusion after other potential etiologies have been investigated and ruled out.  Plan includes patient education on fatigue management strategies, including graded exercise therapy, activity pacing, and stress reduction techniques.  Referral to occupational therapy for activity modification and energy conservation strategies may be considered.  Follow-up scheduled in four weeks to reassess symptom improvement and adjust treatment plan as needed.  ICD-10 code R53.83 is documented for medical billing and coding purposes.  Further investigation may be warranted if symptoms persist or worsen.