Why Do My Hands Go Numb When I Sleep? Causes & Tips

Hands going numb during sleep are usually caused by your sleeping position pressing on a nerve — for example, lying on your arm or with wrists or elbows bent. Moving eases it within minutes. If it wakes you nightly, lasts into the day, or comes with weakness, carpal tunnel syndrome or another nerve problem may be behind it — see a GP.

What happens when your hand “falls asleep”

That dead, heavy, tingling feeling is called paresthesia. According to the NHS, pins and needles happens when the blood supply to a nerve is temporarily cut off — for example, when you sleep on part of your body — and it usually stops within a few minutes once the pressure is off (NHS). Harvard Health notes that when this is intermittent, temporary and linked to holding one position for a long time, it is rarely anything to worry about (Harvard Health).

Common reasons hands go numb at night

Your sleeping position

This is the most common cause. Sleeping on your stomach with your hands under your head, on your side with arms or wrists bent, or on your back with your head resting on your arm can press on nerves or restrict blood flow to the hands (Medical News Today). Posture-related numbness typically clears when you change position.

Carpal tunnel syndrome

Carpal tunnel syndrome is pressure on the median nerve inside the wrist, and its symptoms — tingling, numbness and aching in the hand and fingers — are often worse at night (NHS). The thumb, index, middle and ring fingers are affected, but not the little finger, and symptoms may wake you from sleep — many people “shake out” their hands for relief (Mayo Clinic). You’re more at risk if you repeatedly bend your wrists, are pregnant, are overweight, have diabetes or arthritis, or have a family history of it (NHS).

Ulnar nerve pressure at the elbow or wrist

The ulnar nerve runs along the inside of the elbow down to the little finger. Sleeping with tightly bent elbows can compress it, causing numbness and tingling on the outer side of the hand — the little finger and the little-finger side of the ring finger (Medical News Today). So: thumb-side numbness points to the median nerve (carpal tunnel), while little-finger numbness points to the ulnar nerve.

A trapped nerve in the neck

Neck problems, such as cervical spondylosis — age-related wear of the spinal vertebrae that the AAOS says most commonly affects people aged 60 or older — can press on nerves as they leave the neck and send tingling down into the hands, sometimes worsened by certain sleeping positions (Medical News Today). If numbness travels from the neck or shoulder into the hand, or comes with neck pain, the neck may be the source.

Vitamin B12 deficiency

Vitamin B12 and folate help keep the nervous system healthy, and a deficiency can cause pins and needles, extreme tiredness and muscle weakness (NHS). In the UK, this is more common in older people — it affects around 1 in 10 people aged 75 or over and 1 in 20 aged 65 to 74 — and the most common cause is pernicious anaemia, which stops the body absorbing B12 from food; certain medicines, including some anticonvulsants and proton pump inhibitors, can also reduce absorption (NHS).

Diabetes and peripheral neuropathy

High blood glucose levels can damage nerves and the small blood vessels that supply them over time, causing peripheral neuropathy — numbness, tingling, burning or weakness, often in the hands and feet (Medical News Today). Harvard Health notes that diabetes is the most common identifiable cause of peripheral neuropathy, accounting for nearly a third of cases (Harvard Health).

Raynaud’s, medicines and alcohol

The NHS lists Raynaud’s (pins and needles in fingers or toes that change colour), some medicines — such as HIV medicines, medicines to prevent seizures, or some antibiotics — and heavy alcohol use as possible causes of long-lasting pins and needles (NHS). Harvard Health adds that too much vitamin B6, including from supplements, can also cause neuropathy (Harvard Health).

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Posture or something medical? A quick comparison

Simple steps that may help

• Change your sleeping position. Avoid lying on your hands or sleeping with your arms, wrists or elbows bent, and don’t let your arms hang above your head — straight wrists and elbows reduce nerve pressure (Medical News Today).
• Try a wrist splint at night. A wrist splint keeps the wrist straight while you sleep and relieves pressure on the median nerve; the NHS advises wearing it at night, and says you may need to wear it for up to 6 weeks before it starts to feel better (NHS). (A “wrist brace” is the term used in the US.)
• Ease daytime strain. Take regular breaks from repetitive hand and wrist tasks during the day, and keep your wrists in a relaxed, neutral position when typing (Mayo Clinic).
• Manage underlying conditions. If you have diabetes, arthritis, a thyroid condition or take medicines that might affect your nerves, ask your doctor whether they could be contributing — don’t change any medicine on your own; talk to a doctor or pharmacist first.

When to see a doctor

See a GP if numbness is persistent or keeps coming back, lasts into the day, affects your grip or coordination, or comes with weakness, neck or shoulder pain, colour changes in your fingers, or unexplained tiredness — the NHS advises seeing a GP if you constantly have pins and needles or they keep returning (NHS). Left untreated, carpal tunnel syndrome can lead to permanent weakness, numbness and tingling (MedlinePlus).

Call emergency services right away if hand numbness starts suddenly and severely, or comes with weakness or paralysis, difficulty speaking, confusion, dizziness, chest pain or vision problems, as these can signal a stroke.

In an emergency call 911 (US), 999 (UK) or 112 (EU)