In the short term, the unwanted effects of irradiation depend on the area irradiated. If the digestive tract is included in the radiation field, nausea-vomiting, diarrhea, loss of appetite may occur; irradiation of the skull can cause headaches, vomiting; irradiating the mouth can result in mucosal irritations, decrease in the amount of saliva; irradiation of the skin produces redness and stinging after a while, which can only be treated by the radiotherapist.
It is important to maintain rigorous hygiene in the irradiated area. Any application of creams or substances containing iodine (eg Betadine) can be harmful.
In the long term, irradiation may result in the appearance of a hematological disease (leukemia).
Side effects of radiotherapy that are dependent on the irradiated area can also be:
- Growth inhibition
- Secondary malignancies in the irradiation field (bone and soft tissue sarcomas – breast)
- Head and neck: neurocognitive disorders (changes in memory, speech, coordination), cataracts, hypothyroidism, thyroid cancer, dental abnormalities, pituitary changes (growth disorders), early or delayed puberty
- Chest: cardiac dysfunction (impaired heart function), pulmonary fibrosis (transformation of lung tissue into scar-like fibrous tissue)
- Abdominal/pelvic: malabsorption (impairment of food absorption from the intestine), alteration of gonadal function (impairment of testicles in boys and ovaries in girls), nephritis (inflammatory disease of the kidneys).