Formication is the feeling of insects crawling across or underneath your skin. The name comes from the Latin word “formica,” which means ant.
Formication is known as a type of paresthesia. Paresthesia happen when you feel sensations on your skin that don’t have a physical cause. Paresthesia can take many forms. These can include burning, tingling, or numbness. With formication, you might also describe the “crawling” sensation as feeling like “pins and needles.” Formication is also called a tactile hallucination. This means that you’re feeling a sensation that has no physical cause.
The main symptom of formication is the sensation of bugs crawling on or underneath your skin. This feeling also causes you to feel itchy. This can cause you to scratch your skin where you feel the sensation, even if there’s no actual cause of the itch.
Constant scratching or picking to satisfy an itch can lead to skin damage and open cuts. These open cuts can get infected and lead to other conditions, such as skin ulcers or open wounds.
Formication can happen at the same time as other symptoms, depending on the underlying cause. Other symptoms can include:
- aches around your entire body
- feeling exhausted
- feeling stiff
- difficulty concentrating (often called “fibro fog” in the case of fibromyalgia)
- shaking in hands or fingers, or tremors
- moving slower over time, a symptom of bradykinesia
- feeling depressed
- feeling angry or agitated
Some conditions that may cause formication include:
- Parkinson’s disease
- diabetic neuropathy
- herpes zoster (shingles)
- Lyme disease
- skin cancer, such as cutaneous squamous cell carcinoma
In many cases, formication is most common at night.
Formication can be a symptom of both prescription or recreational drug use. Withdrawal after stopping use of certain drugs can also cause formication. These drugs include:
- eszopiclone (Lunesta), a treatment for insomnia
- methylphenidate (Ritalin), a treatment for attention deficit hyperactive disorder (ADHD)
- bupropion (Wellbutrin), a treatment for depression and for quitting smoking
- ecstasy (sometimes called MDMA or “molly”)
- crystal meth
Alcohol withdrawal, sometimes called delirium tremens, can also trigger formication.
At your appointment, your doctor will want to know:
- any other symptoms that you’ve noticed in addition to formication
- what time of day the crawling sensations are most noticeable
- what medications you’re taking and whether you noticed the sensations after you started taking those medication
- any recreational psychoactive substances that you’re currently using
Giving your doctor a full picture of your symptoms can help them recognize other indications of:
- an underlying condition
- a reaction to medication
- complications from drug use
Formication symptoms are similar to those of scabies. This condition happens when tiny mites burrow into your skin and lay eggs. It’s important for your doctor to identify symptoms that may show that no actual insects are causing your symptoms.
Treatment for formication depends on the cause. A long-term treatment plan may be necessary for fibromyalgia, diabetes, or Parkinson’s disease to manage symptoms and complications. Radiation therapy may be effective for treating formication caused by skin cancer.
In some cases, an antihistamine, such as cetirizine (Zyrtec) or diphenhydramine (Benadryl) may help reduce the crawling sensations. Take these right after the sensation starts to prevent acute itching episodes.
If formication is caused by using prescription or recreational drugs, quitting that drug may help stop the sensation completely. However, don’t stop using a prescription drug without first consulting your doctor. They may recommend an alternative medication that doesn’t cause formication in case you need that type of medication for another condition.
Rehabilitation treatment can help you address addiction to drugs like cocaine or meth. Rehabilitation can also help you manage formication as a withdrawal symptom during your recovery from drug use. Many support groups for drug addiction exist. These can provide you with a community to share your experiences with as you cease drug use.
Complications from untreated conditions that cause formication, such as diabetic neuropathy or Lyme disease, include:
- cuts and wounds that heal slowly
- loss of sensation
- ulcers and abscesses
- heart disease
- kidney disease
Cuts, scabs, and open wounds from constant scratching are a common complication of formication due to the associated itching sensation. Bacterial or viral infections from these cuts can cause:
- pus or discharge from a wound
- heavy bleeding that doesn’t stop (hemorrhage)
- a fever of 101°F (38˚C) or higher
Formication caused by neurological conditions or the use of psychoactive substances like ecstasy can lead to delusional parasitosis. This happens when you believe that actual insects are crawling on you.
Formication is a symptom of an underlying issue that can be treated. Medications for certain conditions and stopping the use of recreational drugs usually help you get rid of this crawling sensation entirely.
See your doctor if you experience frequent episodes of formication. They can make a diagnosis and treatment plan that may be able to stop the sensation altogether.