Hiccups are a nervous spasm of the muscles controlling the diaphragm.
The spasm makes us take a big strong breath that actually triggers our vocal cords into making this well-known sound. Since we don't know why this spasm happens, we cannot be sure what will stop it. When I have hiccups though, all I do is take a very big breath until I can take no more air in and hold it until I absolutely need air again. All rights reserved.