What are the common side-effects of radiotherapy?

What part of body?: In general, radiation may cause skin and mucosal damage: changes in color and thickening ( hardening), dry mouth.; worst scenarios: ulcers or fistulas, scars in internal organs such as lungs; bleeding from sigmoid colon in radiation to the prostate.Tiredness, feeling sick, eating and drinking changes, skin care, hair loss, changes in your blood, possible long-term side effects.

Your question is too: Broad, and has been asked before. The adverse effects deppend on the region treated, the amount of healthy tissues receiving dose, and how much dose. The answer is different from each region from head to toe.