Nerve blocks may involve local anesthesia, regional anesthesia or analgesia, or surgery; dentists routinely use them for traditional dental procedures. Nerve blocks can also be used to prevent or even diagnose pain.

In the case of a local nerve block, any one of a number of local anesthetics may be used; the names of these compounds, such as lidocaine or novocaine, usually have an aine ending. Regional blocks affect a larger area of the body. Nerve blocks may also take the form of what is commonly called an epidural, in which a drug is administered into the space between the spine's protective covering (the dura) and the spinal column. This procedure is most well known for its use during childbirth. Morphine and methadone are opioid narcotics (such drugs end in ine or one) that are sometimes used for regional analgesia and are administered as an injection.

Neurolytic blocks employ injection of chemical agents such as alcohol, phenol, or glycerol to block pain messages and are most often used to treat cancer pain or to block pain in the cranial nerves. In some cases, a drug called guanethidine is administered intravenously in order to accomplish the block.

Surgical blocks are performed on cranial, peripheral, or sympathetic nerves. They are most often done to relieve the pain of cancer and extreme facial pain, such as that experienced with trigeminal neuralgia. There are several different types of surgical nerve blocks and they are not without problems and complications. Nerve blocks can cause muscle paralysis and, in many cases, result in at least partial numbness. For that reason, the procedure should be reserved for a select group of patients and should only be performed by skilled surgeons.

In more details, different nerve blocks have different usages:

• Therapeutic nerve blocks are used to treat painful conditions. Such nerve blocks contain local anesthetic that can be used to control acute pain.
• Diagnostic nerve blocks are used to determine sources of pain. These blocks typically contain an anesthetic with a known duration of relief.
• Prognostic nerve blocks predict the outcomes of given treatments. For example, a nerve block may be performed to determine if more permanent treatments (such as surgery) to block the activity of a nerve would be successful in treating pain.
• Preemptive nerve blocks are meant to prevent subsequent pain from a procedure that can cause problems including phantom limb pain.

Types of Nerve Blocks

Various areas of pain require different nerve block types. Below are a few of the available nerve blocks, followed in parentheses by some of the parts of the body for which they are used.

• Trigeminal nerve blocks (face)
• Ophthalmic nerve block (eyelids and scalp)
• Supraorbital nerve block (forehead)
• Maxillary nerve block (upper jaw)
• Sphenopalatine nerve block (nose and palate)
• Cervical epidural, thoracic epidural, and lumbar epidural block (neck and back)
• Cervical plexus block and cervical paravertebral block (shoulder and upper neck)
• Brachial plexus block, elbow block, and wrist block (shoulder/arm/hand, elbow, and wrist)
• Subarachnoid block and celiac plexus block (abdomen and pelvis)

Types of surgical nerve blocks include:

Side Effects and Risks of Nerve Blocks

• Elevated blood sugars
• Rash
• Itching
• Weight gain
• Extra energy
• Soreness at the site of injection
• Bleeding
• Death (in rare cases)

Although many kinds of nerve blocks exist, this treatment cannot always be used. If your pain isn't related to pain in a single or small group of nerves, nerve blocks may not be right for you. Your doctor can advise you as to whether this treatment is appropriate for you.