A nerve block is an anesthetic injection that numbs the nerves to a part of your body, such as an arm, hand, leg, or foot. It blocks pain signals, so the area feels numb and may not move well during surgery. You may still feel movement or pulling, and the injection usually starts working in 20 to 40 minutes.

Nerve blocks can be used instead of a general anesthetic in some cases, or they can be combined with one to help with pain after surgery. They can give pain relief for up to 24 hours after surgery, and some areas may stay numb for up to 48 hours. Sedation is often used too, which means medicine that helps you feel relaxed and sleepy.

They are often used for surgery on an arm, hand, leg, or foot. Most people are awake during a peripheral nerve block. If the block does not work fully, you may be offered more local anesthetic, extra pain relief, or a general anesthetic.