Do your legs often fall asleep? The tingling and numb sensation affects many people. It can result from several causes, the most common one being excessive pressure on nerves due to prolonged crossing of legs. In most instances, numbness is benign and temporary. However, it may be chronic or episodic and be accompanied by additional symptoms such as itching, muscle atrophy, pain, and itching. It can be a symptom of severe nerve damage due to infection, trauma, diabetes, and exposure to toxins.
Why Do Your Legs Fall Asleep Often?
1. Sitting with Legs Crossed
Your legs may fall asleep if you have the habit of sitting with legs crossed for prolonged periods when standing or squatting. This causes pressure on the nerves and leads to a numb feeling.
This numb feeling or inability to move the legs usually resolves within a few seconds or minutes of stretching. However, there are extreme situations where the prolonged crossing of legs or application of abnormal pressure on the leg causes permanent damage to the peripheral nerves.
2. Vitamin B12 Deficiency
Common symptoms of vitamin B12 deficiency are an abnormal sensation or strange tingling in the legs, numbness, imbalance and staggering. Vitamin B12 is essential to your nerves because it protects the myelin sheath (fatty layer that protects your peripheral nerves). If left untreated, a deficiency can be damaging to your nervous system and cause peripheral neuropathy.
Other symptoms include memory loss, brain fog, depression, fatigue, loss of appetite, hallucinations and disorientation.
3. Fibromyalgia
This is a condition that causes widespread musculoskeletal pain all over the body. It also causes memory problems, insomnia and mood issues. People with this condition may have their legs falling asleep often. They may also experience a tingling sensation in their hands and arms. The numbing and tingling feeling affects about one in four people suffering from fibromyalgia.
4. Multiple Sclerosis (MS)
This is an autoimmune disorder that affects the central nervous system (CNS). It results from damage to the myelin sheath. MS is a chronic condition that progresses over time with patients experiencing remissions and relapses from time to time. Symptoms of MS include:
- Difficulty in maintaining balance
- Fatigue
- Muscle spasms
- Dizziness
Numbness and tingling are the most common symptoms of MS, with the sensations ranging from mild to severe enough to paralyze motor control. These sensations can go into remission without treatment.
5. Diabetic Neuropathies
These are a collection of nerve disorders caused by nerve damage resulting from diabetes. These neuropathies can affect any part of the body, especially the legs and feet. Approximately 70% of diabetic patients suffer from some form of neuropathy.
Having legs falling asleep often is the first common symptom of diabetic neuropathies for most patients and usually gets worse at night. Other common symptoms of peripheral neuropathies include:
- Loss of balance
- Extreme sensitivity to touch
- Sharp pains or cramps in the affected areas
Over time, blisters and sores may develop on the feet and go unnoticed or untreated due to numbness. This can result in infections and poor blood circulation, and may eventually lead to amputations.
6. Peripheral Artery Disease (PAD)
Peripheral artery disease is a condition where the arteries narrow down due to a buildup of fatty acids along the walls of the arteries. This buildup progressively hardens and restricts blood flow to some parts of the body, especially the legs. When this happens, your legs will experience numbness and tingling sensations. If PAD is left without proper treatment, your legs may get infected, and you may end up with gangrene and in extreme cases, a leg amputation.
Due to the severity of the risks of PAD, such as heart attacks and strokes, consult your doctor immediately if you experience any of the following symptoms:
- Leg ulcers or sores that don’t heal
- Color change in your legs to pale blue
- Hair loss or slow growth of hair around the legs and feet
- Cold feet
- Pain in the legs or feet when you are walking or climbing stairs
- Shiny skin around your legs and muscle atrophy
The risk of contracting PAD increases if you are a smoker and/or have a history of heart disease and high blood pressure.
7. Spinal Stenosis
Spinal stenosis is a rare condition in which the spinal cord narrows and increases pressure within it. This pressure affects the nerves within the spinal cord and subsequently causes legs falling asleep often. Spinal stenosis also causes pain and discomfort for the patient. Arthritis is usually the primary cause of spinal stenosis, especially for individuals over the age of 50. Other causes include:
- Birth defects
- Injuries and tumors around the spinal cord
- Bone diseases
- Herniated disc
Spinal stenosis can be managed by using medication, physical therapy and adopting lifestyle changes.
8. Transverse Myelitis
This is a neurological disorder that causes severe inflammation around the spinal cord, subsequently impeding nerve signals. Infections and multiple sclerosis are some of the causes of transverse myelitis. Numbness and tingling in the legs, weakness in the legs and arms, muscle spasms and loose bladder are some of the symptoms of this condition.
It is treated with anti-inflammatory drugs and physical therapy which can significantly alleviate the pain and discomfort and restore a patient’s normal bodily functions.
9. Other Causes
Other possible causes of legs falling asleep often include:
- Frostbite and blood vessel inflammation, thus limiting blood supply
- Shingles and herpes zoster infection
- Abnormal level of minerals such as potassium and magnesium in the body
- Animal bites
- Food toxins
- Back injuries
- Radiation therapy
- Use of some medications
- Some insect or spider bites
Other medical conditions that may cause numbness and tingling include:
- Seizures
- Strokes
- Migraines
- Underactive thyroid
- Mini-stroke
When to See a Doctor
Persistent numbness and tingling may be a sign of a serious underlying medical condition. Call 911 or your local emergency number if you notice any of the following:
- Losing motor control or bladder control
- Feeling confused and disoriented
- Unable to move your leg or arm
- Numbness and tingling after head, neck or back injury
- Blurred vision and slurred speech
Call your medical practitioner in case of the following:
- Recent frequent urination
- Pain in the neck, forearm or fingers
- Numbness and tingling getting worse when you are walking
- Unusual rush
- Dizziness