So I just got back from Peru just last Saturday night. I started getting diarrhea Sunday morning and it still has not stopped (today is Thursday). It's only after I eat a meal. What's wrong with me? Someone help! Could it be because I =had just returned from Peru? Should I seek a doctor? You probably have amoebas...a parasite. In Mexico, the medicine for this is calle OXAL...don't know what it is in the U.S. You DO need to see a doctor tomorrow. The medicine for the parasites usually helps in 2 to 3 days. Ask the doc also for a prescription for lomotil to slow down the diarrhea while the other med is working.