If you force the patients(s) to gain weight then they will most likely feel the need to lose it twice as much as before. Many patients fake getting "better" but lose the weight right after they are let out of the hospital. Doctors and nurses should take the time to teach the patients that they do not need to starve themselves and teach them healthy ways of dieting or they are the appropriate weight for themselves. Patients often develop a fear/hatred of the hospital and doctors and will take extreme measures to ensure they aren't sent there since it will only result in the gaining of weight. Hospitals should teach the patients that there are other ways and there is no need for dieting (if they are underweight).
No, force feeding anorexic patients is not necessarily a treatment, but it may be necessary to ensure that they remain healthy. Anorexia is a sickness and the patient doesn't not understand that they are harming themselves by depriving their bodies of food so force feeding is required,but I do not believe it is a treatment counseling would be be more of a treatment.
No, force feeding anorexia patients is not necessary, because it is not actually treating the disease. Force feeding an anorexic only treats the symptoms of the disease. People who are anorexic are afraid to eat, or they are unwilling to eat for a reason. An anorexic needs psychiatric care, not just a forced intake of calories.