You’re working at your desk, but you’re distracted by tingling or numbness in your hand and wrist. Then a piercing pain shoots from your palm through your arm.

If you’ve had symptoms like these for several days—or worse, weeks—or if they keep you up at night, you may have carpal tunnel syndrome, according to information from the National Institutes of Health.

Carpal tunnel syndrome is caused by a nerve getting pinched inside a narrow passageway—called the carpal tunnel—in your wrist. The rigid tunnel is made of bones and ligament (the tissue that attaches bones to each other). It surrounds several tendons (these connect muscle to the bone) and an important nerve, called the median nerve, that detects feelings in your thumb and fingers (except for the little finger). The median nerve also helps to control certain hand movements.

See your doctor if you have these symptoms:

• Frequent burning, tingling, or itching numbness in the palm and fingers
• A swollen feeling in the fingers (but they may not look swollen)
• Disrupted sleep because of pain or discomfort
• Cramping in the hand or wrist
• Difficulty making a fist or squeezing small objects
• Trouble telling the difference between hot and cold by touch