Lagniappe: Lightning Pear

Pears also contain a nonfermentable sugar called sorbitol, which adds sweetness but has one drawback: for people with sensitive systems, it acts as a laxative. one popular English pear variety, Blakeney Red, is also called Lightning Pear for the way it shoots through the system. This quirk has earned cider pears yet another folk saying: "Perry goes down like velvet, round like thunder, and out like lightning."

Amy Steward, The Drunken Botanist

This explains a lot about why my "morning after" a pear is a bit of a struggle.