What treatments for an elongated large intestine?

Depends on function. The therapeutic approach depends on colon function. An elongated colon may work perfectly well, & therefore require no "treatment." a sluggish colon may respond to prokinetics (designed to speed up movement of material through colon). Colonic inertia that is refractory to prokinetic rx may benefit from "colon reduction" surgery. Sitz marker testing, defecography, anal manometry studies can help.