What is illness anxiety disorder (IAD)?

Illness anxiety disorder (IAD) is a recent term for what used to be diagnosed as hypochondriasis, or hypochondria. People diagnosed with IAD strongly believe they have a serious or life-threatening illness despite having no, or only mild, symptoms. Yet IAD patients’ concerns are to them very real. Even if they go to doctors and no illnesses are found, they are generally not reassured and their obsessive worry continues. IAD can also trigger worries in people who do have a physical illness that they are sicker than they really are. The disorder is not about the presence or absence of illness, but the psychological reaction.

How long can illness anxiety disorder (IAD) last?

IAD may occur once, multiple times, or continuously. The first signs of it are usually seen in early to middle adulthood (ages 25-35), but can come on at any age. It can wax and wane in intensity, but rarely goes away completely.

What are the symptoms of illness anxiety disorder (IAD)?

Symptoms of IAD may include:

  • Excessive worry over having or getting a serious illness.
  • Physical symptoms are not present or if present, only mild. If another illness is present, or there is a high risk for developing an illness, the person’s concern is out of proportion.
  • High level of anxiety and alarm over personal health status.
  • Excessive health-related behaviors (e.g., repeatedly checking body for signs of illness) or shows abnormal avoidance (e.g., avoiding doctors’ appointments and hospitals).
  • Fear of illness is present for at least six months (but the specific disease that is feared may change over that time).
  • Fear of illness is not due to another mental disorder.

What causes illness anxiety disorder (IAD)?

The cause is not known, but certain factors may increase the risk of developing IAD:

  • Major life stress
  • A severe symptom believed to threaten one’s health (e.g., chest pain, memory issues)
  • History of childhood abuse (physical, sexual, emotional) or neglect
  • History of childhood illness
  • Having another mental disorder (e.g., major depression, anxiety, obsessive compulsive disorders, psychotic disorders)

Last reviewed by a Cleveland Clinic medical professional on 07/25/2015.


  • American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Arlington, VA, American Psychiatric Association, 2013.
  • Anxiety and Depression Association of America. DSM-5: Changes to the Diagnostic and Statistical Manual of Mental Disorders Accessed 6/25/2015.
  • American Psychiatric Association. DSM-5 Fact Sheets: Somatic Symptom Disorder (PDF) Accessed 6/25/2015.

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