Separation anxiety disorder (SAD), is an anxiety disorder in which an individual experiences excessive anxiety regarding separation from home or from people to whom the individual has a strong emotional attachment (e.g., a parent, caregiver, significant other or siblings). It is most common in infants and small children, typically between the ages of 6–7 months to 3 years, although it may pathologically manifest itself in older children, adolescents and adults. Separation anxiety is a natural part of the developmental process. Unlike SAD (indicated by excessive anxiety), normal separation anxiety indicates healthy advancements in a child’s cognitive maturation and should not be considered a developing behavioral problem. According to the American Psychiatric Association, separation anxiety disorder is an excessive display of fear and distress when faced with situations of separation from the home or from a specific attachment figure. The anxiety that is expressed is categorized as being atypical of the expected developmental level and age. The severity of the symptoms ranges from anticipatory uneasiness to full-blown anxiety about separation. SAD may cause significant negative effects within areas of social and emotional functioning, family life, and physical health of the disordered individual. The duration of this problem must persist for at least four weeks and must present itself before a child is 18 years of age to be diagnosed as SAD in children, but can now be diagnosed in adults with a duration typically lasting 6 months in adults as specified by the DSM-5.

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