The conditions of ten patients with metastatic renal cell carcinoma were serially evaluated by neuropsychiatric examination to determine the nature of the fatigue-asthenia symptoms resulting from human leukocyte interferon alpha therapy. The majority of the patients had moderate to severe behavioral changes and mild to moderate cognitive, affective, and personality changes within the first week of daily intramuscular administration of 3×106 units of interferon. This descriptive clinical study suggests that the intense fatigue may be a manifestation of a complex neurotoxicity, most suggestive of frontal lobe changes, and resulting in neurasthenia syndrome with reversible impairment of some higher mental functions.
Adams F, Quesada JR, Gutterman JU. Neuropsychiatric Manifestations of Human Leukocyte Interferon Therapy in Patients With Cancer. JAMA. 1984;252(7):938–941. doi:10.1001/jama.1984.03350070056026