Question: what are the side effects of internal radiation?
Answer: Sore vagina. Your vagina may become irritated and sore during radiotherapy. You may also notice an increase in vaginal discharge. ... 
Diarrhoea. Radiotherapy can inflame the lining of your bowel. This can cause diarrhoea. ... 
Bladder problems. The radiotherapy treatment may inflame the lining of your bladder. Symptoms include: