Delusory Parasitosis

Need to Know: 

  • Only a few biting insects can produce skin reactions, and they are all large enough to be easily identified. 
  • In cases where an individual has microscopic organisms present that may bite (e.g., scabies mites), dermatologists are trained to find and identify them. 
  • Sensations and symptoms of insect bites can be caused by many other environmental or medical triggers. 
  • A medical provider should be visited immediately if you notice abnormal skin irritation or marks. 

Overview of delusory parasitosis

A common problem that people encounter is "bites," itching, or skin irritations or crawling sensations that are assumed to be caused by insects but for which no insects or mites can be seen or found. Delusory parasitosis is one of many names used to describe bite-like symptoms caused by non-animal environmental factors. Other names used for the nonexistent arthropods assumed to be the cause of a skin irritation are "paper mite," "sand flea," and "cable mite." There are no such animals as the mythical arthropods just listed.

There are only a few biting insects that produce skin reactions, and these are all large enough to be seen and readily identified. Common biting pests include fleas, head lice, ticks, bat bugs, bed bugs and mosquitoes. Obscure or microscopic organisms that may bite are possible (the most likely being the skin-infesting scabies mite) but these can be isolated and identified by a dermatologist.

Our study of unexplained biting sensations has uncovered several published articles on the topic and a long list of potential causes for "biting" sensations or skin irritation.  We are adamant that insecticide applications are not the answer to perceived problems where no pests can be found and that insecticide use can make unexplained skin irritation worse. We recommend that individuals with unexplained skin irritation work closely with dermatologists and other medical specialists who will help determine the cause of the skin irritation and initiate a suitable resolution.

You can read more about delusory parasitosis at the Wikipedia website.

Common causes of skin irritation

Physical agents

  • dry air
  • static electricity
  • personal and household products; e.g., detergents, cosmetics, jewelry -environmental pollutants
  • microscopic fibers; e.g., fiber glass or paper splinters
  • gases or indoor air pollution; "sick or tight building syndrome"

Physiologic factors

  • allergy
  • diseases and disorders such as diabetes
  • neurological disorder such as shingles

Psychological state

  • anger, anxiety, stress, nerves
Last reviewed:
October 2022

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