Irritability is an excessive response to stimuli. Irritability takes many forms, from the contraction of a unicellular organism when touched to complex reactions involving all the senses of higher animals. In plants response is usually different from that found in animals but is nonetheless present. The term irritability is both used for the physiological reaction to stimuli and for the pathological, abnormal or excessive sensitivity to stimuli.

Irritability may manifest in behavioural responses to both physiological as well as behavioural stimuli - the latter including areas of environmental, situational, sociological, and emotional stimulus.

Causes

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Irritability can result from conditions such as:

• combat stress reaction
• dysmenorrhea
• headache
• hypothyroidism
• lead poisoning
• mastoiditis
• stress
• tiredness

Other uses

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This article is about the medical condition. For the webcomic, see Irritability (webcomic).

Diseases