Table of ContentsView All
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Table of Contents
Side Effect Causes
How Common Are They?
Most Common Side Effects
Effects on Body Systems
How Long They Last
Managing Side Effects
Is Immunotherapy Working?
Immunotherapy is used for a wide variety of cancer types and stages. This type of treatment can be effective but also causes side effects. Most side effects from immunotherapy drugs are mild, but others are severe, life-threatening, and require medical care and even stopping treatment.
Immunotherapy is a cancer treatment approach that uses your immune system to fight against tumor cells. Treatments boost your immune system’s ability to find cancer cells and kill them in various ways.
This article covers everything readers need to know about immunotherapy’s side effects, including the most common side effects, the dangers involved with immunotherapy, how sick the treatment may make you, and if it’s worse than chemotherapy.
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Why Does Immunotherapy Cause Side Effects?
Immunotherapyworks to ramp up the immune system. Some immunotherapy drugs remove blocking effects that typically keep the immune system in check.Immunotherapy side effects stem from an overstimulated or misdirected immune response.
These changes can lead to side effects of an overactive immune system. Sometimes, these side effects are similar to when you’re sick, causing flu-like symptoms or fatigue. Other times, they’re dangerous overreactions that cause severe allergic or autoimmune reactions. These reactions may attack healthy cells, causing immune-related adverse effects.
These side effects depend on what type of immunotherapy you get, what drug you get, your cancer, your general health, and many other factors.
How Common Are Immunotherapy Side Effects?
Mild side effects of immunotherapy occur often. These are potent drugs that have a significant impact on your immune system. Most people getting immunotherapy do not have serious adverse events.
About 20% to 27% of people taking one immunotherapy (immune checkpoint inhibitors) will develop severe adverse effects. If you get two or more types of immunotherapy at once, your risk of severe side effects may be higher—40% to 60%.
Immunotherapy’s most dangerous and life-threatening side effects include infusion reactions, allergic reactions, and autoimmune reactions. These can damage organs and organ systems.
What Are the Most Common Side Effects?
Commonly, immunotherapy can make you feel a bit sick. The everyday mild side effects widely experienced across the spectrum of immunotherapies for cancer include:
How Immunotherapy Affects the Body Systems
Immunotherapy reactions and side effects have widespread effects on the body. These drugs can have specific effects on certain body systems.
Skin
Immunotherapy can cause reactions in the skin. These include itching, a mild rash, and redness. Sometimes called amaculopapular rash, this reaction may be:
More severe but rarer skin side effects include:
Life-threatening skin-related side effects include the development oferythema multiforme major, also calledStevens-Johnson syndrome, a severe form of red, scaly rash that can be fatal.
Mild rashes typically respond well to corticosteroid-based creams, but some may need more intense treatment.They’re more common in people getting immunotherapy formelanomaornon-small cell lung cancer.
Liver and Gastrointestinal (GI) System
Digestive symptoms are common with immunotherapies. These treatments may inflame the gut, a condition calledcolitis. This causes diarrhea, which can be bloody,and abdominal pain.If diarrhea is severe, it can lead to dehydration.
Other immunotherapy side effects in the digestive tract include:
A potential side effect of immunotherapy that doesn’t cause symptoms is liver inflammation (hepatitis). In rare cases, severe hepatitis can cause liver damage, resulting in yellowing of the skin.
Colitis treatment includes drugs to reduce diarrhea and taking in lots of fluids. Severe diarrhea may require hospitalization, infused corticosteroids, and stopping immunotherapy. Rarely, colitis causes a hole in the bowel; it can be life-threatening. It’s treated with surgery and antibiotics.
Lungs and Respiratory System
Immunotherapies can lead to lung swelling (pneumonitis), causing a cough, chest pain, and difficulty breathing. It can be severe if it interferes with breathing.
Studies have shown that these inflammatory lung reactions may happen in 3% to 20% of people getting immunotherapy. It may be more common in current or former smokers.
Other lung-related side effects that have been noted in immunotherapy trials include:
Lung inflammation, even in mild cases, often requires people to stop immunotherapy and start on corticosteroids to improve their breathing. The inflammation comes back in about one-third of people who start immunotherapy again, so they need to be observed.
Thyroid Gland and Endocrine System
Immunotherapy may cause side effects in the endocrine system and its organs. This system uses hormones to regulate many bodily functions. This system is responsible for keeping your blood pressure, energy levels, and stress responses working right.
Hormone replacement therapies can usually counteract these side effects. People with severe complications from immunotherapy should stop their treatment until symptoms resolve.
Brain and Nervous System
Side effects of immunotherapy can impact your brain and nervous system. This can cause changes to your senses, movement issues, and pain and sensation changes calledneuropathy. These are rare but possibly severe side effects.
Complications of immunotherapy on the brain and nervous system include:
Immunotherapies should be stopped or paused immediately and treated if symptoms are severe. If the respiratory muscles are impacted, you may need to be admitted to the intensive care unit (ICU) for close observation and ventilation.
Heart and Cardiovascular System
Side effects of immunotherapy in the heart and blood vessels are rare but can be severe and life-threatening, as follows:
People with these types of complications from immunotherapy need treatment. People with immunotherapy-related arrhythmias can take drugs and may require apacemaker. Immunotherapy may be stopped if symptoms stick around longer than three months, are life-threatening, or you’ll need to stay on immunosuppressive therapies.
Joints
Immunotherapy can impact your joints, muscles, and bones. These changes can cause arthritis-type pain, joint swelling, and muscle cramping.
What About Different Types of Immunotherapy?
All types of immunotherapy work differently, so they tend to have unique side effects and complications.
Immune Checkpoint Inhibitors (ICI)
Some of the more common side effects of checkpoint inhibitors include:
Checkpoint inhibitors can also cause severe rare side effects that can be life-threatening:
Adoptive Cell Therapy (T-Cell Transfer Therapy)
Cell therapies likeT-cell transfer therapyand adoptive cell therapy remove immune cells from the body. These cells are manipulated so they can better find and fight cancer cells when they are returned to the body. Common side effects of adoptive cell therapies include:
Because cell therapies are complex procedures, they also have complex complications.Cytokine release syndromeis when high levels ofcytokines(signaling proteins of the inflammatory process) enter the blood and send the immune system into overdrive. Severe cases can cause problems with many organs in the body.
Cytokine release syndrome can cause:
Immune effector cell-associated neurotoxicity syndrome, which affects a person’s nervous system, can occur with adoptive cell therapies.Unique symptoms include:
Cell therapies may decrease bone marrow function. Your bone marrow makes blood cells, leading tolow levels of red blood cells,platelets, andwhite blood cells. These changes can weaken the immune system, raising the risk of infections. They can also cause bleeding issues.
Other complications include:
Monoclonal Antibodies
Side effects of monoclonal antibodies include:
More complex and severe reactions can occur with antibody treatments. These include:
Other reactions are specific to the target of the antibodies. These include:
Treatment Vaccines
Typically, vaccines are used to prevent or weaken infections and the illnesses they cause. But cancer treatment vaccines spur the immune system to fight back against cancer. They can cause side effects, including flu-like symptoms.
Other common side effects of cancer vaccines may include:
These are also possible:
Some cancer vaccines can cause herpesvirus infection. Symptoms include:
Immune System Modulators (Immunomodulators)
Immune system modulators are drugs that turn the immune system up. This can have many side effects, including flu-like symptoms. Cytokines are a type of immunomodulator drug naturally found in the body. Cytokine drugs can have serious side effects, including:
Other immunomodulators, such as Thalomid (thalidomide), Revlimid (lenalidomide), and Pomalyst (pomalidomide), can cause side effects that include:
How Long Immunotherapy Side Effects Last
Most immunotherapy side effects may start with the first treatment, but some—especially more complex complications—may come later. Most will clear up when you stop immunotherapy. Chronic side effects persist for more than three months after treatment has stopped.
Regarding checkpoint inhibitors, 43% of people in one study had lingering, chronic side effects; 96% of these long-term side effects were mild. They included rashes, thyroid issues, and joint pain.
But there are some instances in which side effects or complications from treatment will crop up months or years after you’ve finished. These are called late or long-term side effects.
Often, people want to compare the side effects of different cancer treatments. This isn’t easy to do since many are very personal. Some people have very mild side effects of immunotherapy, while others have life-threatening reactions and must stop treatment. Chemotherapy is less likely to cause life-threatening side effects.
Compared to chemotherapy, immunotherapy is generally well tolerated. But often, someone on immunotherapy may stay on it for a long time, while chemotherapy is given in cycles for a set amount of time. Then, the side effects you get on chemotherapy and immunotherapy are different:
Chemotherapy vs. Immunotherapy: Uses, Benefits, Side Effects, and More
How to Manage Immunotherapy Side Effects
If you have side effects of immunotherapy treatments, mention them to your care team. They may have ways of treating these side effects or want to monitor these side effects for changes or if they become more problematic. Report any changes in your health to your care team, even if you don’t think they’re related to your treatment.
If your side effects are moderate to severe, your cancer treatment may need to stop while you are treated for the side effects. Sometimes, you can restart treatment. If the side effect returns, you may need to stop altogether.
You can take some steps to lessen mild side effects at home. While getting cancer treatment, try your best to eat a healthy diet and stay hydrated. Focus on fruits and veggies, low-fat foods, and protein-rich snacks.
If you’re having digestive distress while on checkpoint inhibitors, try these tips:
Listen to your body and get rest when you need it. Ask your friends and family to pitch in so you can take it easy. If you’re emotionally challenged with your cancer, cancer treatment, or side effects, talk to your care team about additional mental health support for your anxiety and stress.
Do Side Effects Mean Immunotherapy Is Working?
Side effects could indicate that the treatment is effective for at least some specific checkpoint inhibitors. Because these side effects are related to the immune system’s increased activity, they may also mean the immune system is attacking the cancer.
But this isn’t the case in people who are getting other immunotherapies or those who are also getting other cancer treatments (combination therapies). This is not necessarily true for other cancer treatments. For example, no proof exists that having more or fewer side effects from chemotherapy means it is working.
However, that also doesn’t mean a lack of side effects indicates the treatment won’t work.
Summary
Immunotherapy is a treatment that boosts your immune system to fight cancer. It can be effective but may have side effects. Immunotherapy side effects range from mild to severe. Common side effects include joint pain, flu-like symptoms, digestive issues, headaches, and skin problems.
Immunotherapy can affect different body systems. These include the skin, liver, lungs, thyroid, and nervous system, causing various symptoms. Severe side effects include infusion reactions, autoimmune reactions, and organ damage. These are less common.
Side effects and complications depend on the type of immunotherapy. Checkpoint inhibitors can cause digestive issues and skin problems. Adoptive cell therapy may lead to kidney damage and neurological symptoms.
Immunotherapy side effects may appear with the first treatment. Many will go away when you stop treatment. Chronic side effects last longer than three months. In some cases, immunotherapy side effects could indicate the treatment is working.
Manage side effects alongside your healthcare team. Keep a healthy diet, stay hydrated, and get light exercise.
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