Based on the experiences of helminth hosts over the past 10 years and scientific and medical literature spanning over a hundred years, we believe that the controlled introduction of benign intestine-dwelling helminths such as Necator americanus and Trichuris Trichiura are, in most cases, safe. However, due to the experimental nature of the treatment, no one can know for certain how any individual will react. (For information on known contraindications see previous question: “Who shouldn’t use this treatment?”)
According to the CDC, most people infected with hookworm/whipworm have no symptoms though it is possible for anaemia to be an issue if someone has a very large number of worms present in their intestines. However, this is highly unlikely with the dose sizes we use.
Furthermore, neither organism can proliferate in the body so the infections can never run out of control; the total number of worms you will have residing in your intestines at any point in time will never exceed the sum of the doses you have applied.
If for any reason you decide to kill off your symbionts you can do so relatively easily with a course of albendazole.