Immunotherapy can cause side effects. Many side effects happen when the immune system that is 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 your cancer is
• the type and dose of immunotherapy you are getting

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 talk with your doctors and nurses about 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:

Investigating Cancer Immunotherapy Side Effects

Researchers aim to better understand, manage the side effects of these new drugs.

• pain
• swelling
• soreness
• redness
• itchiness
• rash

Learn more about skin changes caused by cancer treatment.

You may have flu-like symptoms, which include:

• fever
• chills
• weakness
• dizziness
• nausea or vomiting
• muscle or joint aches
• fatigue
• headache
• trouble breathing
• low or high blood pressure

Other side effects might include:

• swelling and weight gain from retaining fluid
• heart palpitations
• sinus congestion
• diarrhea
• infection
• organ inflammation

Some types of immunotherapy may cause severe or fatal allergic and inflammation-related reactions. But, these reactions are rare.

Certain side effects might happen depending on the type of immunotherapy you receive. Visit the page for the type of immunotherapy that you are receiving for more details about serious side effects. Types of immunotherapy include:

• immune checkpoint inhibitors
• t-cell transfer therapy
• monoclonal antibodies
• treatment vaccines
• immune system modulators

Have Questions?

Connect with our cancer information specialists.

Phone: 1-800-4-CANCER 
Chat: LiveHelp
Email: NCIinfo@nih.gov

Available Monday–Friday 9:00 a.m. to 9:00 p.m. ET.