i may have found out a way to prevent hiccups, it might be a discovery because one day after school i grabbed a piece of triangular bread for a snack (i like Triangular bread ok) and i felt some gland that felt irregular feeling which would of caused hiccups. i just tried to move the gland around and took some deep breathes once there was nothing in my throat and the feeling was gone.
No idea if this will work again or for you