What is Periodic Limb Movement Disorder?

Curated by Claudia Shannon / Research Scientist / ishonest

What causes periodic limb movement disorder?

Although the exact cause of PLMD isn’t currently known, many researchers believe that PLMD originates in the central nervous system. However, no official link has yet been made. The following are all thought to contribute or influence PLMD but aren’t necessarily considered a cause:

  • caffeine intake
  • medications like antidepressants, anti-nausea drugs, lithium, and anticonvulsants
  • other sleep disorders such as narcolepsy or RLS
  • neurodevelopmental disorders like attention deficit hyperactivity disorder and Williams syndrome
  • spinal cord injury
  • iron deficiency anemia
  • metabolic disorders including diabetes and kidney disease

PLMD is more common among older adults. According to the Sleep Health Foundation, it affects only about 2 percent of people less than 30 years of age, but it may affect up to 40 percent of people age 65 years and older. PLMD affects men and women equally.

What are the symptoms of periodic limb movement disorder?

ishonest No.313 - Prevent Acne

No.313 - Prevent Acne

PLMD movements typically occur every 20 to 40 seconds in batches of 30 minutes or more during the night. They are more common in the legs but may occur in the arms as well. The limb movements typically occur during non-rapid eye movement (non-REM) sleep.

The most common symptoms of PLMD include the following:

  • repetitive leg movements in one or both legs and sometimes in the arms, which may involve flexing of the big toe, upward bending of the knee or ankle, or twitching of the hip
  • restless, unrefreshing sleep
  • multiple awakenings at night
  • daytime sleepiness and drowsiness
  • irritability, behavior problems, and decline in performance at school or work due to lack of quality sleep

How is periodic limb movement disorder diagnosed?

Often people first become aware that they may have PLMD when their partner complains of being kicked at night. Or they may find that their blankets are all over the place in the morning.

PLMD is diagnosed with a polysomnography test, also called a sleep study. This study is done overnight in a laboratory while you sleep. This test records:

  • brain waves
  • heart rate
  • oxygen levels in your blood
  • eye movements
  • other nerve and muscle functions during sleep
  • blood pressure
Get personalized, clinically effective skincare formulated for you based on your skin, life and environment

Learn more

It’s usually done at a sleep disorders unit in a hospital or at a designated sleep center. A sleep technologist places sensors on your scalp, temples, chest, and legs using medical glue or tape. The sensors are then connected to a computer with long wires, and measurements are taken all through the night while you’re asleep.

Your doctor may also get your complete medical history and give you a physical exam to look for other underlying issues that may be disrupting your sleep. Urine and blood samples are often taken to look for signs of iron deficiency anemia and any metabolic disorders. Low iron and metabolic disorders such as diabetes have been linked to PLMD.

How is periodic limb movement disorder treated?

Treatment for PLMD will depend on the results of the sleep study and other diagnostic tests as well as the severity of your disorder. It may also depend on whether you have another sleep disorder, such as RLS.

Treating the underlying condition

If you’re diagnosed with iron deficiency or another medical condition, treatment is aimed at the underlying condition. Your doctor may want to monitor your iron levels over time and prescribe an iron supplement or recommend a diet high in iron-rich foods.

Taking medications
ishonest No.171 - Pre-Sun Exposure

No.171 - Pre-Sun Exposure

For severe cases of PLMD, medications that regulate muscle movements may be prescribed as a last resort. These include:

  • dopamine agonists, which are commonly prescribed to control tremors in people with Parkinson’s disease
  • benzodiazepines such as clonazepam (Klonopin)
  • anticonvulsants such as gabapentin (Neurontin, Gralise, Horizant)


PLMD isn’t a life-threatening condition. However, a good night’s sleep is important to everyone. If you have PLMD or can’t sleep well at night, your doctor can refer you to a sleep specialist for help.

Read more on: movement

What we do

We make skincare treatments and customize them for your skin-related problems, genetics, lifestyle, and environment.

How you benefit

You get total control over your skincare and the choice to change your skin. An impossible has just become possible.

How Custom Beauty Works

Desktop Mobile Graphic
Take the Quiz

Tell us about your skin, general health, lifestyle, environment, and all your skin goals. The quiz takes 4-8 minutes.

Outline of microscope
Create Your Treatment

Our algorithm creates a unique routine with a few customized products. The algorithm uses 50+ years of skincare research.

Outlines of Packaging
Divide and Rule

Every product is designed for one problem. Apply the product when the problem appears. Much like you treat flu or headache.

Product Values

A family sharing common values functions effortlessly and effectively. So do our products. All our products share these values.

Outline of bulb

Typical skincare routines confuse your skin with 20-50 ingredients. Our custom routines contain 1-8 ingredients, sending clear signals to your body to use the ingredients and recover faster.

Outline of Green Leaf

Our skin can use only active ingredients, also called actives. Most products contain up to 10% actives, whereas our products contain at least 90% actives. You get better value. Your skin avoids junk food.

Get Started

Never Used Before

Take the quiz below and discover a customized treatment for your unique skin-related problems, lifestyle, and environment.

Know Your Treatment

Every treatment has a unique 3-digit ID. You can find the ID on the product label. Search the ID on top right corner or click below.

Targeted Solutions

If a particular skin problem is bothering you, browse our products for your specific problem. You can customize your routine later.