I found a good site and explanation for this common symptom that we with KD have often.
http://www.voicedoctor.net/therapy/laryngospasm.html

Very helpful post!

I kind of had discovered on my own that breathing in very slowly during a "choking" episode was the best solution. This paragraph from the article confirms:

"With the Bernoulli principle in mind, one can see that slower breathing in will effectively get more air into the lungs than rapid breathing in. In fact, we spend most of our life breathing out, as in talking, then we take a quick breath in and spend more time talking. When one has an episode of laryngospasm, one can reverse this usual trend and take most of your time to breath in slowly and then a quick breath out can be followed by another slow breath in. This can be repeated until the spasm stops."

Another benefit of breathing in slowly is that it doesn't scare the crap out of those around you!

I'll second that - Very helpful! I wasn't sure that these alarming episodes were attributable to KD, but this so accurately describes what I experience that I'm now in little doubt.

It is interesting to note that an episode of larnygospasm ("dry drowning") is caused when food or water touch the vocal bands. Here's a quotation from the www.voicedoctor.net website:

"As soon as your voice box or the area of the windpipe below the voicebox detect the entry of water or other substance, the vocal folds spasm shut. Evolutionarily speaking, this works very well to keep water out of the lungs - if you start to drown or a bug flies down your throat while you were starting to inhale, or you inhale that glass of water, then the vocal cords very immediately and very effectively close."

A contributing cause is weakness in the throat muscles. There is a very good, and easy, exercise that strengthens the swallowing muscles in the throat, and that helps to reduce the laryngospasm. The exercise is described at this website:
http://www.mcw.edu/display/docid26360.htm

Also check out the KDA forum under \Exercise discussion\Swallowing exercise?\