I wouldn't be able to hand that!

Yes, this is listed on the official insert:
from http://www.rxlist.com/cgi/generic/gabapent_ad.htm

And yes edema is very common. Many quit Neurontin because of it.

The way that Neurontin works is by blocking "signals" in the spinal cord, before they reach the brain (hopefully just the pain signals)
But I suspect this drug is non-specific to some extent like most drugs are.

Here is the Mayo report on fecal incontinence--
http://www.mayoclinic.com/health/fec...477/DSECTION=3

With your special circumstances you may just be more likely to have this effect than others.
I personally don't recall any posters with this side effect.
But just about everyone gets some form of edema.