8 causes of foul-smelling stool - Medical News Today 8 causes of foul-smelling stool - Medical News Today Posted: 10 Apr 2019 12:00 AM PDT Foul-smelling stool has a particularly bad odor. Often, this is due to the foods that people eat. In some cases, however, foul-smelling stool can indicate an underlying medical condition. This article outlines eight causes of foul-smelling stool, along with information on diagnosis, treatments, and when to see a doctor. Share on Pinterest In some cases, antibiotics can cause foul-smelling poop. People taking antibiotics may experience temporary stomach upset and foul-smelling stool. This is because antibiotics can disrupt the delicate balance of good and bad bacteria within the gut. Symptoms usually disappear soon after finishing a course of antibiotics, once the good gut bacteria have replenished. Occasionally, antibiotics can destroy so many of the good intestinal bacteria that the har