Agrypnia excitata represents a triad of three subgroups of disorders having similar clinical characteristics, namely, delirium tremens caused by alcohol withdrawal, fatal familial insomnia (an autosomal dominant prion disease) and Morvan syndrome (autoimmune encephalitis). All three disorders are characterised by motor, autonomic and hormonal hyperactivity. Clinically, the involvement of the peripheral, central and autonomic nervous systems combined with insomnia symptomatology should be considered indicative of agrypnia excitata because early diagnosis and treatment is essential for preventing disease-related mortality. Herein, we present the case of a patient who was admitted with complaints of sudden-onset diplopia, loss of balance, hallucinations and insomnia and diagnosed with delirium tremens. A literature review, including data obtained most recently on agrypnia excitata, delirium tremens, fatal familial insomnia and Morvan syndrome, was conducted with this context.
