Numbness

Numbness is a loss of feeling in part of your body. It can be complete, with no sensation at all, or partial, where things feel duller than usual. It often comes with tingling or a prickling feeling, sometimes called pins and needles, and usually points to a problem somewhere along a nerve.

What are the common causes of numbness?

Temporary numbness is usually caused by:

• sitting or lying in one position for too long, or wearing tight clothes or shoes, which puts pressure on a nerve or reduces blood supply to it.

Longer-lasting or recurring numbness can have a range of causes, including:

• diabetes, which can damage the small nerves in the hands and feet over time
• a trapped or compressed nerve, for example from a slipped disc, carpal tunnel syndrome, or a nerve pinched by arthritis
• poor circulation, such as with Raynaud's, where blood vessels in the fingers and toes narrow
• a lack of vitamin B12
• some medicines, including certain chemotherapy drugs, older HIV medicines, and anti-seizure medicines
• drinking too much alcohol.

Less commonly, numbness can be a sign of something more serious, such as a stroke, multiple sclerosis, a tumour affecting the brain, spine or a nerve, or an injury to the spinal cord.

Are there different types of numbness?

Numbness can be complete, with no feeling at all, or partial, where sensation is reduced but not entirely gone. It's often accompanied by tingling, burning, or a pins-and-needles feeling, the medical term for which is paraesthesia.

It also helps to think about where and how it happens:

• temporary numbness that comes on from sitting or lying in one position, and clears within minutes once you move
• numbness affecting a single area, such as one hand or foot, often linked to a nearby trapped or compressed nerve
• numbness affecting both sides of the body, or spreading over time, which is more often linked to an underlying health condition.

How is numbness diagnosed?

A GP will ask about when the numbness started, how long it lasts, what you were doing at the time, and whether you have any other symptoms. They'll examine you, checking your pulse and blood pressure, and testing how well you can feel touch, pinpricks or vibration in the affected area.

Blood tests can check for diabetes, anaemia and vitamin B12 levels. If needed, you may be referred for further tests, such as nerve conduction studies or a scan, to look more closely at the nerves, spine or brain.

How is numbness treated?

If numbness is temporary and linked to sitting or lying awkwardly, loosening any tight clothing and moving or shaking the affected limb is usually enough to bring feeling back.

For longer-lasting or recurring numbness, treatment depends on the cause. For example:

• a trapped nerve in the back or neck may improve with physiotherapy, and avoiding heavy lifting, repetitive movements or poor posture
• diabetes-related numbness is managed by keeping blood sugar well controlled
• a vitamin B12 deficiency is treated with dietary changes or supplements
• persistent nerve pain may be treated with specific nerve pain medication
• some causes, such as a tumour or a severe spinal problem, may need surgery.

When should I see a doctor?

See a GP if:

• numbness keeps coming back, or doesn't fully go away
• it doesn't have an obvious cause
• it happens during a repeated activity or motion
• you notice a loss of strength or muscle control building up over time
• it comes with a rash

Call 999, or go to A&E, if numbness:

• comes on suddenly
• affects an entire arm, an entire leg, or one whole side of your body
• affects your 'saddle area', meaning your inner thighs, buttocks or genitals
• comes with a new loss of bladder or bowel control
• spreads quickly to other parts of your body
• comes with confusion, slurred speech, vision changes, weakness, or difficulty breathing

These can be signs of a stroke, a serious spinal problem, or another condition that needs urgent care.