According to the Mayo Clinic, hand numbness is usually caused by damage, irritation or compression of one of the nerves or a branch of one of the nerves in your arm and wrist.

Diseases affecting the peripheral nerves, such as diabetes, also can cause numbness, although with diabetes similar symptoms usually occur first in your feet.

Uncommonly, numbness may be caused by problems in your brain or spinal cord, although in such cases arm or hand weakness or loss of function also occurs. Numbness alone isn’t usually associated with potentially life-threatening disorders, such as strokes or tumors.

Your doctor will need detailed information about your symptoms to diagnose the cause of your numbness. A variety of tests may be needed to confirm the cause before appropriate treatment can begin.

Possible causes of numbness in one or both of your hands include:

Brain and nervous system conditions

• Cervical spondylosis
• Guillain-Barre syndrome
• Paraneoplastic syndromes of the nervous system
• Peripheral neuropathy
• Spinal cord injury
• Stroke

Trauma or overuse injuries

• Brachial plexus injury
• Carpal tunnel syndrome
• Cubital tunnel syndrome
• Frostbite

Chronic conditions

• Alcohol use disorder
• Amyloidosis (buildup of abnormal proteins in your organs)
• Diabetes
• Multiple sclerosis
• Raynaud's disease
• Sjogren's syndrome

Infectious diseases

• Lyme disease
• Syphilis

Treatment side effects

• Side effects of chemotherapy or HIV drugs

Other causes

• Ganglion cyst
• Vasculitis
• Vitamin B-12 deficiency

Causes shown here are commonly associated with this symptom. Work with your doctor or other health care professional for an accurate diagnosis.

Source: Mayo Clinic