The laxative senna has all of the following features, except:
a) It frequently causes abdominal gas.
b) It is available at health food stores as a “natural” product.
c) It requires transformation to active drug in the gut.
d) It stimulates the dorsal root ganglion to increase gut motility.
Senna-based products are inexpensive, safe, and effective for mild-moderate
constipation, available by prescription or over-the-counter. Senna is in the class of
stimulant laxatives. Senna is broken down by bacteria in the colon to metabolites that
stimulate the myenteric plexus, but has no known activity at the dorsal root ganglion
(answer d). Senna can lead to abdominal gas and bloating.
See Fast Fact #15 Constipation