What Causes Irritability in Adults?

Irritability is an emotional state characterized by feelings of frustration or annoyance, according to the medical website Wrong Diagnosis. Irritability has many causes, the most common of which is a stressful life situation. Irritation that does not go away, however, could also indicate a mood or anxiety disorder or any number of medical conditions.

Stressful Life Situations

Many stressful situations can cause a temporary feeling of irritability, such as when things don't go as planned. It is normal for an individual to feel irritable for short periods of time. The National Multiple Sclerosis Society cites several different methods to decrease irritability and stress that may prove useful such as eliminating sources of stress, learning not to focus so strongly on life's smaller problems, relaxation and physical activity. When chronic irritability does not respond to such measures, however, it may indicate a more serious condition such as a mood or anxiety disorder.

Mood and Anxiety Disorders

Both bipolar disorder and certain anxiety disorders can lead to feelings of irritability. A manic episode comprises one manifestation of bipolar disorder, and is characterized by a period of expansive, elevated or irritable mood lasting at least one week, along with other symptoms. If the mood is irritable, four other symptoms must also be present, and may include grandiosity, decreased need for sleep, flight of ideas, difficulty concentrating, agitation and excessive involvement in pleasurable activities that might be damaging, according to the American Psychiatric Association.

Irritability is clearly a manifestation of bipolar disorder only if it occurs constantly and not only in specific situations. It must also be accompanied by others bipolar symptoms.

Anxiety disorders may also lead to feelings of irritability. Irritability is one of the features associated with generalized anxiety disorder, or GAD, according to the American Psychiatric Association. GAD's hallmark feature is a chronic feeling of worry, which must be present for diagnosis. The addition of irritability and other symptoms such as restlessness and fatigue will confirm the diagnosis.

Post-traumatic stress disorder sometimes presents with feelings of irritability in addition to its hallmark feature of extreme fear or dread regarding memories of a traumatic event, according to the American Psychiatric Association.

Medical Conditions

Many physical and medical conditions can result in feelings of irritability. According to Wrong Diagnosis, these include hypothyroidism, diabetes, flu, Graves disease, Alzheimer's disease and many other brain conditions. Irritability may be a secondary emotional development of chronic illness or pain.

To determine whether the root cause of chronic irritability is medical or emotional, clinicians recommend a thorough medical exam and history, as well as a neurological exam and sometimes cognitive testing, according to Wrong Diagnosis.