Numbness in the hands can be a warning sign of a range of dangerous diseases.

Carpal tunnel syndrome

The carpal tunnel is a narrow passage formed by connective tissue and small bones in the palm of the hand. Tendons and nerves pass through it.

Carpal tunnel syndrome is a condition involving inflammation or narrowing of the tunnel, which puts pressure on the nerves inside due to prolonged, continuous hand and finger movements. This causes numbness in the fingers and hand, and can even lead to stiffness and difficulty gripping objects.

Give your hands a rest if you don't want to develop this syndrome. You should see a doctor if your hand numbness occurs frequently and shows no signs of improvement. It can cause permanent damage to nerves and muscles if left untreated.

Nerve pain

If cartilage, muscles, or tendons put too much pressure on a nerve, it can prevent it from functioning properly, causing numbness. If this happens frequently, it can lead to arthritis, cartilage erosion, spinal calcification, or the formation of tumors on the spine.

People should not be complacent if they frequently experience numbness in their hands, forearms, or fingers, as this is a warning sign of many dangerous diseases.

Symptoms may include: sharp or burning pain, a stinging or pins-and-needles sensation, weakness or numbness in the arm.

Migraine with aura

Some migraines are accompanied by auras or flashes of light that can affect your vision and other senses, including causing numbness in the hands.

Arm numbness typically begins after 1 hour and lasts for less than 1 hour. Other symptoms of this type of migraine include:

- Changes or reductions in vision, including blind spots.

- Seeing zigzag lines, rays of light, or stars.

- Muscle weakness.

- Difficult to say or express.

Diabetes

High blood sugar levels can cause diabetic neuropathy – damage to the nerves.

This condition typically begins with numbness in both legs or both hands, along with other symptoms including:

- Itching or a sensation like being bitten by an insect.

- Pain or cramps.

- Increased sensitivity to touch (the weight of clothing or bedding can cause you pain).

- Muscle weakness.

- Loss of reflexes, especially in the ankles.

- Serious foot problems such as ulcers, infections, and joint pain.

There is no cure for this disease, but doctors can prescribe medication to reduce the symptoms.

Nerve diseases

Nerve-related conditions such as multiple sclerosis can also cause numbness in the hands and feet. If you experience numbness in your hands or feet, or have problems with speech or concentration, see a doctor for examination and treatment.

Side effects of chemotherapy

Some types of cancer chemotherapy can damage nerves, leading to numbness, tingling, and pain in your arms, legs, fingers, toes, or other areas of your body. It feels like you're wearing a thick, tight glove.

Stroke

A stroke occurs when a blood vessel carrying blood to the brain ruptures or becomes blocked by a blood clot. Besides numbness in the arms or legs, a stroke can cause weakness, confusion, difficulty seeing, difficulty speaking, and other symptoms.

Heart attack

Although other signs of a heart attack (such as chest pain, shortness of breath, and cold sweats) are more common than numbness in the hands, if this occurs frequently, you may also be at risk of heart disease.