Pruritus (Itching):Definition, Causes, Symptoms.


What Is pruritus?

Pruritus is the sense of incessant, uncontrollable itching. The specific cause of pruritus can be hard to pin down as it can harm anyone with any type of skin. Some people are more sensitive to the condition, such as those with seasonal diseases, pregnant women, diabetics, people with HIV/AIDS, and the old aged.

An itch is an uncomfortable feeling beneath the skin that causes the urge to scratch. At any given interval, 8-9 percent of the population experience skin itchiness that lasts 2-3 weeks. It is estimated chronic, however, when it lasts lengthier than 6 weeks. Itching can be localized to specific areas of the body.

Several ailments are linked to itchy skin, however, not all of them are skin disorders. These involve psoriasis, internal diseases such as kidney failure or liver disease, nerve disorders like diabetes, psychiatric disorders like obsessive-compulsive disorder, allergic reactions, and pregnancy. In unusual cases, pruritus can not be fully restored but can be managed through things like medications, topical treatments, and the delay of skin irritants.

Causes Of Pruritus

While the signs of pruritus are pretty straightforward, the cause is not. Various factors can bring on the urge to scratch, varying from external irritants to serious internal illness. Sometimes detecting the underlying cause of the pruritus needs extensive evaluation. Cause fall into four categories:

  • Cutaneous- Infection and swelling of the skin
  • Neuropathic- means an irregularity in the nervous system
  • Neurogenic- An itch that arises from something internally but not due to a problem with the nervous system
  • Psychogenic- Occurs while delusional states

Some of the more frequent cause of persistent itching include:


Allergies are a frequent cause of pruritus and can stem from a response to pollen, food, and certain substances. They cause the release of histamine and different chemicals in the body which can lead to an extreme itch.

Dry skin

Dry skin or xerosis can occur for various reasons including normal ageing, inflammatory skin disease, usage of harsh soaps or detergents, dry weather situations and bathing too frequently. It can also be caused by the infirmities like diabetes.

Bug bites and parasitic infection

Bug bites are reasonably common and can result in redness and swelling around the area of the bite. Parasite like pinworms, lice or scabies is also a usual cause of the persistent itching.


Psoriasis is not entirely understood but is an immune-mediated condition where the skin cells grow unusually fast. This occurs in lesions and rashes that can be itchy

Measles, chickenpox, and other viral infections

Chickenpox and measles, two extremely contagious viral infections usually associated with childhood, can cause irregular pruritus. Measles presents a body-wide rash that typically begins on the face and grows downward toward the feet. Chickenpox, on the other hand, produces hundreds of itchy blisters that light on the chest and back and dispersed to other parts of the body. The itching connected with these viral infections lasts for a few days to a week and subside when the person recovers. Other viruses, like HIV, shingles and hepatitis C can also generate excessive itching.


Approximately 20% of pregnant women experience pruritus. While in most utmost cases it’s due to dry skin, there can be other more severe underlying causes. One of these causes is intrahepatic cholestasis of pregnancy which occurs in a change in bile flow from the river. This condition usually occurs in the second or third trimester. The disorder in bile flow causes skin lesions and severe itching, especially at night. If not managed, ICP could cause injury to the developing fetus.

Liver or kidney problems

Liver diseases including cirrhosis, cholestasis, non-alcoholic fatty liver disease and drug-induced liver damage often cause pruritus. This type of irritation usually gets worse at night. It can likewise be exacerbated by heat, hormonal changes, or contact with wool. Kidney failure can also be an underlying problem of pruritus.

Other causes

Additional causes of pruritus involve exposure to harsh chemicals, certain medications, some cancers, thyroid dysfunction and psychiatric disorders.


Itchy skin can change small areas, such as the scalp, an arm or a leg, or the whole body. Itchy skin can occur without any other notable changes on the skin. Or it may be correlated with:

  • Redness
  • Scratch marks
  • Dry, cracked skin
  • Lethargy patches

Sometimes itchiness lasts a prolonged time and can be intense. As you scrape or scratch the area, it gets itchier. And the more it itches, the more you scrape. Breaking this itch-scratch cycle can be challenging.