Chappy I found this:
"The respiratory and the circulatory system are most affected by tobacco use. Once in the bloodstream, nicotine activates cholinergic receptors. These receptors are usually activated by the neurotransmitter, acetylcholine, which is produced in the brain and by neurons in the nervous system. Acetylcholine and its receptors are involved in many functions; including muscle movement, breathing, heart rate, learning, and memory. Nicotine's chemical makeup is similar to the Acetylcholine and therefore able to activate the receptors. When nicotine gets into the brain, it attaches to acetylcholine receptors and mimics the actions of acetylcholine.
But, it can disrupt the normal functioning of the nervous system where information adjusts the outgoing messages that control contraction or changing in breathing patterns, resulting in a hiccup."
http://www.helium.com/items/1395150-...-cause-hiccups