Interferon treatment is not easy. My partner was on it for four months, the first month the IV infusion and the next three months the sub-cutaneous injections three times a week. He suffered severe depression, extreme fatigue, uncontrollable itching and some aches. He was put on Remeron, an antidepressant, and that seemed to work pretty well. Benadryl and Atarax were tried for the itching, to no avail.
He was exhausted to the point that he slept 18-20 hours a day. Had he not been retired, there is no way he would have been able to work.
It is extremely important to keep yourself well hydrated; minimum of 2 litres of fluid per day, and coffee, tea, and other caffeinated drinks are to be avoided, as they are diuretic, and draw fluid out of your body. I know of one person under treatment who drank two gallons of fluid a day, and had very little trouble with fatigue after starting that. My partner never would drink the requisite amount of fluid, and that may have been why he suffered so from the fatigue.