Hi: Yes take son to doc for stool tests to confirm parasitic infection.Some natural treatments for a teen would be the addition of garlic( a whole clove) to diet for 2-3 days followed by 1 tbsp of blackstrap molasses in a cup of warm water this will move the bowels and help expell parasites.Check bowel movements for parasite. Don't use any other para meds until your dr checks stool to see if they are present.Post again with results; will give more recommendations.