Immunotherapy can cause side effects, many of which happen when the immune system that has been revved-up to act against the cancer also acts against healthy cells and tissues in the body. Different people have different side effects. The ones you have and how they make you feel will depend on how healthy you are before treatment, your type of cancer, how advanced it is, the type of Immunotherapy you are getting, and the dose.
You might be on Immunotherapy for a long time, and side effects can occur at any point during and after treatment. Doctors and nurses cannot know for certain when or if side effects will occur or how serious they will be. So, it is important to know what signs to look for and what to do if you start to have problems.
Some side effects are common with all types of Immunotherapy. For instance, you might have skin reactions at the needle site, which include:
You may have flu-like symptoms, which include:
- Nausea or vomiting
- Muscle or joint aches
- Trouble breathing
- Low or high blood pressure
Other side effects might include:
- Swelling and weight gain from retaining fluid
- Heart palpitations
- Sinus congestion
- Risk of infection
- Organ inflammation
Some types of Immunotherapy may cause severe or even fatal allergic and inflammation-related reactions. However, these reactions are rare.