Parasitic worm infections (helminthiasis) can cause a range of symptoms depending on the type and severity. Common signs include abdominal pain, diarrhea, nausea, vomiting, fatigue, and unexplained weight loss. Some individuals may experience itching around the anus, especially with pinworms, or visible worms in stool. Nutrient deficiencies and anemia can develop in chronic cases. Respiratory symptoms may occur if larvae migrate through the lungs. Skin rashes or swelling can also appear. Treatment often involves antiparasitic medications like Nitazoxanide, and drugs such as nizonide 500mg are commonly prescribed to eliminate the infection effectively.