Medicinsk godkendt artikel
A Gon blockade (blockade of the nervus occipitalis major, which in English is called GReater OCcipital Nerve) can interrupt or attenuate seizures in patients with cluster headache.
The blockade consists of adrenal cortex hormone combined with a local anesthetic.
A Gon blockade works by numbing the nerve, which is located around the edge of the skull on both sides of the neck. Thus, nerve impulses are prevented from reaching the brain. The effect typically occurs within 1-7 days and may be effective for up to 3 months.
The Gon blockade is generally well tolerated. You may become sore and due to the local anesthetic you may experience numbness around the injection site for a few hours. In rare cases, and typically if you have had repeated blockades, hair loss and indentation in the tissue around the insertion site may occur.
If Gon blockades are given more often than every 3 months, the risk of the above side effects increases and there is a risk of serious side effects such as osteoporosis, influence on fat distribution (moon face) and inhibition of the immune system and of the adrenal glands.
If you have diabetes, you should be extra aware that your blood sugar may be higher than usual, typically in the first few weeks after the blockade is placed.
If you have an ongoing infection in your body, a Gon blockade can make this worse.
It is the therapist who decides whether the Gon blockade should be placed on one or both sides.
The nerve is found by the therapist measuring out approximately midway between the bone protrusion behind the ear and the middle of the neck. Often, even with a finger, you can feel the point exactly where you are sore. It is sprayed off and the blockade is injected with a thin needle and distributed in 3-4 places to anesthetize the entire area.
The treatment may feel uncomfortable and you may sweat.
A dent may appear where the blockade is laid. This is harmless and disappears within a few hours as the fluid is distributed in the tissue.
If you feel comfortable, you may want to drive home after getting a Gon blockade. The first time the blockade is put in place, you have to wait 15 minutes to go home.
