Primary polydipsia symptoms, such as delusions involving fluid intake or other unusual behaviours. Primary polydipsia may have physiological causes, such as autoimmune hepatitis. Since primary polydipsia is a diagnosis of exclusion, the diagnosis may be made for patients who have medically unexplained excessive thirst, and this is sometimes incorrectly referred to as "psychogenic" rather than "primary" polydipsia. As a diagnosis of exclusion, a diagnosis of primary polydipsia may be the result of elimination of the possibility of diseases causing similar signs and symptoms, such as diabetes insipidus. Diagnosis may be complicated by the fact that chronic and extreme compulsive drinking may impair
Functional neurological symptom disorder Functional neurological symptom disorder A functional neurological disorder (FND) is a condition in which patients experience neurological symptoms such as weakness, movement disorders, sensory symptoms and blackouts. The brain of a patient with functional neurological symptom disorder is structurally normal, but functions incorrectly. According to consensus from the literature and from physicians and psychologists practicing in the field, functional symptoms are also called 'medically unexplained'. Historically, other terms have been used to describe these symptoms. Symptoms of functional neurological disorders are clinically recognisable, but are not categorically associated with a definable organic disease. The intended contrast is with an organic