After taking deworming drugs, intestinal parasites will have some reactions because of the effect of the drugs, and some of them will wander around in the intestines or twist into clusters, so many people will have abdominal pain and can even feel a hard knot in the abdomen. 2.After the parasites are killed, some drugs can also dissolve the parasites in the body, which will release some toxins in the process, thus causing some irritation to the intestinal mucosa, and some people will have diarrhea as a result. 3.When the parasites are killed, it will affect the function of the intestinal system and affect the digestive function of the human body, so some people will be accompanied by nausea and vomiting. These reactions are normal after taking worming medicine, and they will gradually disappear after 2-3 days.