Delusional parasitosis (DP) is a rare psychiatric (mental) disorder. A person with this condition strongly believes that they’re infected with a parasite. However, this isn’t the case — they don’t have a parasitic infection of any kind.

This illness is also called Ekbom syndrome or delusions of parasitosis. A parasite is an organism that depends on its host to survive. Parasites can include mites, fleas, lice, worms, and spiders.

A person with this condition can’t control or stop these thoughts or beliefs. They’re not choosing to believe they have a parasitic infection.

There are three types of delusional parasitosis:

  • Primary delusional parasitosis. This is when a person has one delusional belief. It’s a monosymptomatic, or one symptom, illness.
  • Secondary delusional parasitosis. This is when a person also has other mental health conditions, like depression, dementia, obsessive-compulsive disorder (OCD), bipolar disorder, post-traumatic stress disorder (PTSD), or schizophrenia.
  • Organic delusional parasitosis. This can happen to someone with other conditions or illnesses, like hypothyroidism, diabetes, heart disease, vitamin B-12 deficiency, cocaine addiction, and menopause.

A person with delusional parasitosis may often see a doctor or dermatologist (skin doctor) for treatment, insisting that they have a parasitic infection inside their body or on their skin.

The only sign of delusional parasitosis in some may people may be their conviction that they have a parasite inside them. They may also believe that their furniture, home, or surroundings are also infested with this parasite.

Another common symptom people with delusional parasitosis report is a crawling feeling on their skin. The medical term for this is formication.

Some people with this disorder may also have symptoms like:

  • feelings of itchiness or burning
  • feeling of numbness
  • complaining that they have a crawling or prickling feeling under the skin
  • scratching at the skin
  • picking at the skin
  • skin lesions or ulcers caused by scratching
  • using chemicals to scrub the skin
  • self-mutilation, in serious cases
  • using dangerous home remedies, like harmful pesticides, on themselves

It isn’t known why some people have delusional parasitosis. This mental health condition is most common in women of middle age or older. However, both men and women of any age and race can have it.

In some cases, delusional parasitosis happens after a chemical imbalance in the brain from other health conditions. It may also be linked to drug use or addiction, such as cocaine addiction.

It isn’t known exactly where in the brain this condition happens. Some researchers believe the brain chemical dopamine plays a role in psychosis (believing, seeing, or hearing something that isn’t there). Severe stress or other illness can lead to too much dopamine in the brain.

If you think you may have this condition, your doctor will do a complete physical exam. They may also run blood tests to help rule out other causes for skin itching, crawling, numbness, and other symptoms similar to those of delusional parasitosis.

These other possible conditions include:

Treatment for delusional parasitosis includes treating any underlying conditions. If there’s a triggering illness, treating that illness can help ease or stop the delusional parasitosis.

A doctor or psychiatrist may prescribe antipsychotic medications. A person with delusional parasitosis may not wish to take these medications because they believe they have a parasitic infection rather than a mental health condition.

Therapy and talking with a trusted doctor and psychiatrist may help. It’s important to see a psychiatrist, as many family doctors and dermatologists aren’t familiar with medications and treatments for this kind of condition.

A psychiatrist may prescribe antipsychotic medication for delusional parasitosis, such as:

  • pimozide (Orap)
  • aripiprazole (Abilify)
  • risperidone (Risperdal)
  • olanzapine (Zyprexa)

People with delusional parasitosis can’t always be talked out of this condition. In these cases, a doctor can provide a referral to a psychiatrist.

If you’re trying to help someone with delusional parasitosis, doctors warn that you should never try to trick them into taking antipsychotic medication by saying it’ll get rid of the parasites. This could backfire and make them believe more strongly that they have a parasitic infection.

Like other mental health conditions, treating delusional parasitosis may take time and need several visits to doctors and psychiatrists. One kind of treatment may not work for everyone with this condition.

However, one or more kinds of treatment and therapy from a trusted psychiatrist may help ease or end symptoms.

Delusional parasitosis is a rare psychiatric disorder. This condition can be overwhelming for both the individual and their family and friends.

But it’s important to know that there are treatments and people, including trusted doctors and psychiatrists, who can help ease symptoms. A strong support system can also help relieve some stress and discomfort.

Delusional parasitosis may be linked to an underlying chronic condition or other mental health condition. To diagnosis the condition, a doctor may carry out a careful examination and do several blood tests and scans. Finding the right treatment plan for this condition may also take time.