Side effects of radiation


Radiation (also called radiation therapy or radiotherapy) is an important therapeutic approach in the treatment of oncological diseases (cancer). It is usually used in combination with chemotherapy and operations. The side effects of radiation treatment can therefore often not be clearly separated from the complications of the other treatment options.

In addition, the various therapeutic approaches sometimes have very similar side effects, which mutually reinforce each other. Since the aim of the irradiation is to destroy tumor cells, the side effects are often based on the destruction of healthy cells.

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The causes of the side effects of radiation lie in the radiation itself. Radiation therapy is used to destroy tumor cells. Since the rays cannot be directed exclusively at diseased cells, a lot of the surrounding tissue is also irradiated. This gives rise to the side effects of radiation.

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For example, high radiation exposure can lead to an acute radiation reaction with reddening of the skin and inflammation of the irradiated areas. For example, if a lot of lung tissue is irradiated, radiation pneumonitis (an inflammation of the lungs caused by radiation) occurs, with shortness of breath, fever and coughing. When bone marrow is irradiated, the blood-forming cells are damaged, which is why anemia (anemia) and a lack of white blood cells (Leukocytopenia) and platelets (thrombocytopenia). Due to the lack of white blood cells, the immune system is severely weakened and infectious diseases can occur. The lack of platelets can lead to major bleeding or even life-threatening blood loss.

Chronic radiation damage can also be triggered by radiation. Various organs can be permanently damaged, leading to functional disorders, for example in the intestines or the thyroid gland. If the radiation hits the ovaries or testicles, it can lead to infertility. The radiation damages the egg cells and sperm or can lead to changes in the genetic make-up there. The change in the genetic make-up in other cells also increases the risk of cancer recurring in the irradiated area.

Read more on the subject at: Long-term effects after radiation treatment


Since the side effects of radiation are very diverse, their diagnosis is also very different. For the definition of the side effect or consequence of radiation, radiation therapy in the affected area must be present in the medical history. If there are then symptoms that can be explained by the cell damage after radiation, one can often assume a side effect from the radiation.

I recognize these symptoms as a side effect of radiation

The symptoms of radiation side effects are as varied as the types of side effects. In the acute case during or shortly after the radiation, an acute radiation reaction can occur, which is accompanied by nausea and vomiting as well as difficulty swallowing. Headaches and a pronounced feeling of weakness, which may be accompanied by a fever, can also be symptoms of the side effects of radiation.

The skin over the irradiated area is often reddened, which can lead to overheating, swelling, pain and inflammation. Mucous membranes that are affected by the radiation can also become painfully inflamed.

Typical symptoms of side effects of radiation to the bone marrow are pronounced paleness and poor performance (anemia), susceptibility to infections (low white blood cells) and a tendency to bleed (reduced number of blood platelets). If the lungs are irradiated, a dry cough with coughing up blood and shortness of breath can occur. In the long run, regeneration damage can occur in the irradiated body regions. The affected cells are permanently damaged. For example, irradiated bones can break particularly easily, and they only grow together very slowly or hardly at all, so that adequate fracture healing is not possible.

The damage to organs makes itself felt through a functional weakness. This can lead to increased or decreased hormone releases. Intestinal dysfunction with pronounced abdominal pain and diarrhea are also signs of the side effects of radiation in the abdominal cavity.

Treatment / therapy

Treating the side effects of radiation is anything but trivial. First of all, the best treatment is good radiation planning. For example, as little healthy tissue as possible should be included in radiation therapy. For this purpose, three-dimensional radiation plans are made nowadays, which are calculated as best as possible by computers. It must be ensured that the tumor tissue is irradiated as strongly as possible, while the surrounding tissue should be well protected. If a high dose of radiation is necessary to treat the tumor, the radiation can be extended over a longer period of time.

Read more on the subject at: Radiation therapy planning

This reduces the side effects of the radiation, as the healthy tissue always has some time to recover from the radiation. In the case of acute radiation reactions, causal therapy is not possible, since radiation cannot be dispensed with. Instead, symptomatic therapy can be used. It is important that affected people take in sufficient fluids and enough nutrients and energy in spite of the symptoms, so that the body can tolerate the consequences of radiation as well as possible. Side effects such as nausea and vomiting can be alleviated with medication.

Duration / forecast

The duration of the side effects of radiation often depends on the intensity and duration of the radiation. Acute radiation reactions often last a few days and can reappear quickly if the patient is exposed to another radiation. Chronic radiation reactions, on the other hand, often go unnoticed for several months or a few years. However, they can then break out and seriously impair the quality of life and expectation of life (for example, new tumors caused by radiation).

Course of disease

The course of the side effects of radiation varies depending on the tissue affected. Acute inflammation of the tissue often occurs very quickly after irradiation, lasts for a few days, comes back faster and faster with renewed irradiation, but also subsides permanently after the end of the radiation therapy. Chronic radiation damage, on the other hand, only develops over time and then tends to increase in severity. A new therapy for these long-term side effects may be necessary.

How contagious is that?

The side effects of radiation are usually not contagious. The trigger of the disease lies in the radiation. This only affects the person treated with the radiation and cannot be transferred to other people. Even infectious diseases can often be traced back to a pronounced immune deficiency, which is why healthy people are often not easily infected with it. Rather, it is important to protect the irradiated person well, as they run the risk of being infected by other people with a wide variety of supposedly harmless pathogens.