“Is radiation treatment worse than chemo?”

Not necessary, depending on location. You may not feel any at all, such as to the breast. You may feel nausea if you receive treatment to the abdomen or stomach area.

As you’ve probably surmised, every treatment intervention is associated with side effects. Chemotherapy is referred to as systemic treatment, because it is routed through the body, after being administered either via the veins as a fluid, or by mouth as a pill. Because of this systemic distribution, chemotherapy can affect more areas in the body, thus generally causing a wider range of side effects. Radiation Therapy is local treatment, i.e., it is directed to the site of the cancer only. Thus, other parts of the body that are not in close proximity to the cancer site, are not affected by radiation. However, there is one radiation therapy side effect that is not localized to the site of treatment; and that is fatigue (tiredness). So, in response to your question, I would not ascribe ‘worse’ or ‘better.’ Rather, it is accurate to state that chemotherapy generally causes more side effects because of its systemic capacity. 
I hope that the above response adequately addresses your question.

Sincerely, 

Dr. EB