It is typically the phrenic nerve that causes this problem. If you're unable to resolve it yourself, trying finding a person trained in visceral manipulation in your area. They're taught to gently manipulate the phrenic nerve for a number of different conditions. Check the www.iahp.com website for advanced practitioners.
I agree with SLadylani. It does have to do with the Phrenic nerve which is the motor supply of the Diaphram. I learned a little trick that might help. Take an ice cube and hold it on your neck just under your ear. The Phrenic nerve runs behind the Carotid artery. Rub it back and for in that area for as long as you can take. The cold is supposed to calm the nerve which stops the hiccups. Good luck!
Sounds like you have a problem with your phrenic nerve. The phrenic nerve that excites the muscles of the diaphragm, for reasons unknown, lapses into uncontrollable spasms which causes hiccups. Perhaps you could discuss with your doctor the benefits and risks of a nerve block, or try chiropractory in the mean time. Chiroprators may be better able to reach the nerve then an accupuncturist. Best of luck!
Sara RN