TIL about Delusional parasitosis, sometimes referred to as phantom infestation, is a psychological disorder in which an individual mistakenly believes their body is overrun by living or inanimate entities. Typical examples of these perceived invaders include bugs, worms, or microbes.

[u/1998199888]

https://en.wikipedia.org/wiki/Delusional_parasitosis

[u/Ducking_over_it]

Hey I’ve seen this! I had a patient with clear Lewy body dementia that had a long standing delusion of being infested with liver flukes. He went so far as to shit in a bucket to avoid contaminating the water supply (even though he disposed of it in the toilet later), rubbing bleach all over his body, and setting his couch on fire to rid it of the bugs. He also had vivid visual hallucinations of the bugs crawling on him. One of the saddest and most impaired cases I’ve ever seen.