Loss of Feeling: Causes and How to Protect Numb Skin

What loss of feeling is like

People describe it in different ways:

• a dull, "dead" or wooden feeling
• feeling as if you are wearing gloves or socks when you are not
• not feeling the floor properly, or feeling as if walking on cotton wool
• not noticing hot water, a stone in your shoe or a cut
• tingling, buzzing or burning along with the numbness

When numbness affects the feet, balance often suffers, because the brain relies on signals from the soles to keep you steady. Many people first notice unsteadiness in the dark or in the shower when they close their eyes.

For the medical terms, patterns of sensory loss and how neurologists localize them, see loss of sensation.

Common causes

Diabetes

Diabetic neuropathy affects up to half of people with long-standing diabetes. It starts in the toes and spreads up the feet and legs, then may affect the fingers. It often comes with burning or tingling at night. Numb feet are the main reason people with diabetes develop foot ulcers and amputations.

Squeezed or pinched nerves

• Carpal tunnel syndrome: loss of feeling in the thumb, index and middle fingers, often at night.
• Ulnar nerve compression at the elbow: numb ring and little fingers.
• Sciatica and other pinched nerve roots: numbness down the leg into the foot with back pain.
• Pressure on nerves from crossing legs, tight boots or leaning on the elbows.

Vitamin deficiencies and alcohol

• Vitamin B12 deficiency: numbness and tingling in the feet and hands, fatigue, unsteadiness and memory problems. Risk is higher with a vegan diet, older age, metformin, long-term acid-suppressing drugs and after weight-loss surgery.
• Heavy alcohol use damages nerves directly and through poor nutrition.

Other nerve causes

• chemotherapy and some other medicines
• underactive thyroid, kidney disease and liver disease
• HIV, Lyme disease, shingles and leprosy
• autoimmune conditions such as Sjogren's syndrome and lupus
• inherited neuropathies

Brain and spinal cord causes

• Stroke causes sudden numbness, usually on one side of the body.
• Multiple sclerosis causes patches of numbness that develop over days and may come and go.
• Spinal cord compression causes numbness below a level on the body, often with weakness and bladder changes.

Circulation problems

Poor blood flow from peripheral artery disease or Raynaud's phenomenon can cause cold, numb fingers or toes, especially in the cold or with walking.

What to tell your doctor

To find the cause, a doctor will want to know:

• exactly where the numbness is and whether it is on one or both sides
• whether it started suddenly or gradually, and whether it is spreading
• whether you also have tingling, burning, weakness or balance problems
• about diabetes, alcohol, diet, medicines and recent illnesses
• whether you have back or neck pain, or bladder or bowel changes

They will test your feeling to light touch, pinprick, vibration and position, check reflexes and strength, and look at your feet. Blood tests (glucose and HbA1c, B12, thyroid, kidney function) and nerve conduction studies are common next steps. MRI is used when a spinal or brain cause is suspected.

Protecting areas with lost feeling

Numb skin can be injured without you noticing. Simple habits prevent serious harm:

• Check your feet daily, using a mirror or asking someone to help, for cuts, blisters, redness, swelling or color changes.
• Test bath water with your elbow or a thermometer. Aim for below about 37 °C (98.6 °F).
• Never walk barefoot, even at home. Check shoes for stones before putting them on.
• Wear well-fitting shoes and socks without thick seams. People with diabetes may qualify for protective footwear.
• Avoid heating pads, hot water bottles and sitting close to heaters with numb skin.
• Use oven gloves and be careful with hot pans and sharp tools if your hands are numb.
• Prevent falls: use night lights, remove loose rugs, and consider balance exercises or a cane if your feet are numb.
• See a podiatrist for nail and callus care if your feet are numb.

Treatment

Treatment depends on the cause:

• tight blood sugar control slows diabetic nerve damage
• B12 injections or tablets for deficiency
• stopping alcohol and good nutrition
• splints, injections or surgery for trapped nerves
• physical therapy for back and neck problems
• emergency treatment for stroke or spinal cord compression

Burning nerve pain that often accompanies numbness can be treated with medicines such as duloxetine, pregabalin, gabapentin or amitriptyline, prescribed by a doctor. Some feeling may return after the cause is treated, though nerves recover slowly.

Frequently asked questions

What causes loss of feeling in the feet?

The most common cause is nerve damage from diabetes. Other causes include vitamin B12 deficiency, heavy alcohol use, chemotherapy, kidney disease, an underactive thyroid, a pinched nerve in the lower back and poor circulation. Blood tests and a nerve exam can usually identify the cause.

What causes loss of feeling in the hands?

Loss of feeling in the hands is usually from carpal tunnel syndrome or ulnar nerve compression at the elbow, a pinched nerve in the neck, or widespread neuropathy. Sudden numbness of one hand with weakness or speech problems can be a stroke and needs a 911 call.

Can loss of feeling come back?

Often, partially or fully. Feeling usually returns when a squeezed nerve is released, B12 is replaced or a disc problem settles, although nerves regrow slowly. Long-standing diabetic neuropathy is harder to reverse, but good blood sugar control can stop it getting worse.

Is loss of feeling serious?

It can be. Brief numbness from sitting awkwardly is harmless. Persistent numbness needs a cause found, and sudden one-sided numbness is an emergency. Even mild numbness in the feet increases the risk of unnoticed injuries, ulcers and falls, so protection is important.

What is the difference between numbness and tingling?

Numbness is reduced or absent feeling. Tingling, or pins and needles, is an abnormal extra sensation. They often occur together because both come from irritated or damaged nerves. Tingling sometimes appears first and numbness follows as nerve damage progresses.