(Redirected from Irritable)
Jump to navigation Jump to search

WikiDoc Resources for Irritation


Most recent articles on Irritation

Most cited articles on Irritation

Review articles on Irritation

Articles on Irritation in N Eng J Med, Lancet, BMJ


Powerpoint slides on Irritation

Images of Irritation

Photos of Irritation

Podcasts & MP3s on Irritation

Videos on Irritation

Evidence Based Medicine

Cochrane Collaboration on Irritation

Bandolier on Irritation

TRIP on Irritation

Clinical Trials

Ongoing Trials on Irritation at Clinical

Trial results on Irritation

Clinical Trials on Irritation at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Irritation

NICE Guidance on Irritation


FDA on Irritation

CDC on Irritation


Books on Irritation


Irritation in the news

Be alerted to news on Irritation

News trends on Irritation


Blogs on Irritation


Definitions of Irritation

Patient Resources / Community

Patient resources on Irritation

Discussion groups on Irritation

Patient Handouts on Irritation

Directions to Hospitals Treating Irritation

Risk calculators and risk factors for Irritation

Healthcare Provider Resources

Symptoms of Irritation

Causes & Risk Factors for Irritation

Diagnostic studies for Irritation

Treatment of Irritation

Continuing Medical Education (CME)

CME Programs on Irritation


Irritation en Espanol

Irritation en Francais


Irritation in the Marketplace

Patents on Irritation

Experimental / Informatics

List of terms related to Irritation


Irritation or exacerbation, in biology and physiology, is a state of inflammation or painful reaction to allergy or cell-lining damage. A stimulus or agent which induces the state of irritation is an irritant. Irritants are typically thought of as chemical agents (for example phenol and capsaicin) but mechanical, thermal (heat) and radiative stimuli (for example ultraviolet light or ionising radiations) can also cause irritation.

Irritation also has non-clinical usages referring to bothersome physical or psychological pain or discomfort.

Irritation in organisms

In higher organisms, the allergic response may be cause of irritation. An allergen is defined distinctly from an irritant, however, as allergy requires a specific interaction with the immune system and is thus dependent on the (possibly unique) sensitivity of the organism involved while an irritant, classically, acts in a non-specific manner.

In humans, it is a mild form of suffering, often with anger about the suffering; in particular, if applicable, anger at the person who caused it. This can also be oneself, e.g. when forgetting something or doing something one deems to be stupid.

It is a form of stress, but conversely, if one is stressed by unrelated matters, mild imperfections can cause more irritation than usual: one is irritable; see also sensitivity (human).

In more basic organisms, assigning irritation the status of pain is the perception of the being stimulated - which is not observable although it may be shared (see gate control theory of pain).

It is not proven that oysters can feel pain, but it is known that they react to irritation. When an irritating object becomes trapped within an oyster's shell, it deposits layers of calcium carbonate (CaCO3), slowly increasing in size and producing a pearl. This serves no purpose to the oyster, pearls do not attract mates for the oyster or perform any other function. It seems impossible to find an evolutionary advantage for the ability to produce the pearl, thus it can be explained only as a reaction to an irritation.

It has also been observed that an amoeba avoids being prodded with a pin, but there is not enough evidence to suggest how much it feels this. Irritation is apparently the only universal sense shared by even single-celled creatures.

It is postulated that most such beings also feel pain, but this is a projection - empathy. Some philosophers, notably René Descartes, denied it entirely, even for such higher mammals as dogs or primates like monkeys - Descartes considered intelligence a pre-requisite for the feeling of pain.

See also

de:Irritation Template:WH Template:WikiDoc Sources