Selection of treatment regimens depends on disease severity, disease location, and disease-associated complications. Various guidelines recommend that approaches be sequential - initially to induce clinical remission, and then to maintain remissions. Initial evidence of improvement should be seen within 2 to 4 weeks and maximal improvement should be seen in 12 to 16 weeks 3 . The classic approach to therapy in Crohn's disease has been a "step-up" approach starting with the least toxic agents for mild disease, and increasingly more aggressive treatment for more severe disease, or patients who have not responded to less toxic agents. More recently the field has been moving toward a "top-down" approach (early aggressive management) which might decrease exposure to anti-inflammatory agents and increase exposure to agents that enhance mucosal healing that might prevent future complications 4 .
Medications that are used to kill roundworms are called ascaricides . Those recommended by the World Health Organization for ascariasis are: albendazole , mebendazole , levamisole and pyrantel pamoate .  Other effective agents include tribendimidine and nitazoxanide .  Pyrantel pamoate may induce intestinal obstruction in a heavy worm load. Albendazole is contraindicated during pregnancy and children under two years of age. Thiabendazole may cause migration of the worm into the esophagus , so it is usually combined with piperazine.