Emotion › Morbid Disorder of Emotion

Irritability

Irritability, as a morbid disorder of emotion, is a sustained, pathological lowering of the threshold at which a person becomes annoyed, frustrated, or angry, so that minor provocations that would not normally bother them readily trigger a disproportionate irritable or angry response. It represents a persistent state rather than an occasional bad mood, and can occur as part of a depressive illness, an elevated mood state, or a range of other conditions.

This has traditionally been recognised as a feature that can accompany a range of underlying emotional disturbances, appearing both in depressive illness, where it may substitute for or accompany overt sadness, and in states of elevated mood, where it can emerge when a person's expansive plans or wishes are thwarted.

Recognition features

• A persistently lowered threshold for annoyance, frustration, or anger, present across a range of situations
• Minor, everyday provocations trigger a disproportionately strong irritable response
• Represents a sustained change from the person's usual temperament, rather than an isolated instance of being in a bad mood
• Can accompany either low mood or elevated mood states, and is not specific to one direction of mood disturbance

Eliciting it at interview

• Ask the person, and where possible those close to them, whether they have noticed themselves becoming more easily annoyed or short-tempered than usual
• Ask for specific recent examples of minor triggers producing a disproportionate irritable reaction
• Consider irritability alongside a full mood history, since it can be a presenting feature of either a depressive or an elevated mood state

Distinguishing features

• Differs from ordinary bad temper by its persistence and its representing a genuine change from the person's baseline temperament
• Differs from affective incontinence, in which the display goes beyond irritability to a loss of control over sudden laughing or crying
• Not specific to depressive illness or to elevated mood, and can be a useful clue prompting a broader assessment of underlying mood state

Common misconceptions

• That irritability is only a feature of low mood; it is equally recognised as a feature of elevated mood states, particularly when a person's plans or wishes are obstructed
• That being irritable is simply a personality trait; a marked, sustained change from a person's usual temperament is a recognised clinical sign worth assessing further

Related phenomena

Morbid Disorder of Emotion · Depressive Illness · Morbid Euphoria · Excitement

Diagnostically relevant to

Bipolar I Disorder · Major Depressive Disorder (links open the DSM-5 Learning Lab)

Practice this

Over recent weeks, a patient has become persistently quick to anger at minor, everyday provocations that would not normally trouble him, a change clearly noticed by his family as being unlike his usual, easy-going temperament, though he retains full control over his reactions. What is this? · Following a neurological illness, a patient bursts into sudden, uncontrollable laughter or tears at minor or even neutral remarks, with the intensity and nature of the display markedly disconnected from how she actually reports feeling at the time, and she cannot bring the display under control once it begins. Before revealing the answer: is this irritability? · A patient shows a pattern of quick, disproportionate anger. Before revealing the answer, decide what distinguishes impulsive personality disorder from irritability. · A patient shows a heightened emotional reactivity. Before revealing the answer, decide what distinguishes irritability from affective incontinence. · A patient's family reports that he has become unusually short-tempered. Before revealing the answer, decide how you would explore whether this is irritability. · Explain why irritability is described as a useful clue prompting a broader assessment of underlying mood state, rather than being specific to any one direction of mood disturbance.

Illustration

Over the past month, a 34-year-old man, normally easygoing according to his partner, has snapped angrily at his children over trivial matters like a dropped toy or a slow internet connection, reactions entirely out of keeping with how he has handled similar minor frustrations in the past.

References

• Casey, P. & Kelly, B. (2019). Fish's Clinical Psychopathology, 4th ed. Ch. 6, 'Disorders of Emotion'.