My 16 Yr Old Has Not Had A Stool For

My 16 yr old has not had a stool for one month this week, He took almost 10 Different products. In emergency he got enemas,laxatives and was also prescribed laxatives again, he took stool softeners, he was ordered to drink 2 bottle citrus magnesium together with laxatives , he also too the power mixture and had a colonoscopy, he still can not poop and is in pain, four doctors said he is ok! he still is in pain and can not attend school and is losing weight fast, he lost about 15 pounds in the 3 weeks. he cries and is stress that he is missing school.