Immunotherapy Side Effects

If you are currently experiencing side effects or unusual symptoms after receiving immunotherapy, contact your medical team or doctor immediately.

Immunotherapy side effects differ fundamentally from those of traditional cancer treatments like chemotherapy and radiation therapy. While chemotherapy and radiation target both cancerous and healthy cells, immunotherapy works by stimulating the immune system to attack cancer cells. This heightened immune response can sometimes become overstimulated or misdirected, causing side effects.

These immune responses can impact any tissue or organ, resulting in side effects that range from mild discomfort to severe, potentially life-threatening conditions. 

Recognizing these side effects early on and managing them effectively, often with immunosuppressive drugs such as steroids, is crucial for maintaining safety and treatment efficacy.

Patients undergoing immunotherapy are encouraged to communicate any unusual symptoms to their healthcare providers promptly to ensure any necessary adjustments to their treatment plan can be made swiftly.

What Are the Most Common Immunotherapy Side Effects?

The most common side effect of immunotherapy is skin reactions, including rash, itchiness, and redness, particularly at the injection site. However, the side effects of immunotherapy can vary depending on the type of cancer, the immunotherapy treatment plan, the stage of cancer, and your overall health. Other common immunotherapy side effects include:

• Gastrointestinal Issues: Such as diarrhea or colitis.

• Flu-Like Symptoms: Fever, chills, fatigue, and muscle aches are frequently reported.

• Respiratory Problems: Some patients may experience coughing or difficulty breathing.

• Endocrine Disorders: Conditions like hypothyroidism or adrenal insufficiency can occur.

In general, the side effects most commonly experienced across the spectrum of the current FDA-approved immunotherapies may include but are not limited to:

Explore side effects specific to certain types of immunotherapies

Side effects for immunotherapy vs other cancer treatments

Do side effects mean immunotherapy is working?

A positive response to immunotherapy typically manifests as a reduction in tumor size or the stabilization of tumor growth, which can be objectively measured through imaging scans. 

While the presence of side effects such as inflammation may indicate that the immune system is reacting to the treatment, these symptoms alone do not reliably predict treatment success. In fact, many patients who respond well to immunotherapy experience few or no side effects.

How long do side effects from immunotherapy last?

Immunotherapy side effects can appear within days of starting treatment, but they more commonly develop several weeks or months later. Some side effects, such as infusion-related reactions or injection site pain, can occur shortly after treatment is administered. The frequency of side effects can also vary based on the patient’s treatment regimen and overall health.

Side Effects Specific to Different Types of Immunotherapies

While some side effects overlap across various immunotherapy treatments, each type of immunotherapy has its own unique set of possible side effects. Understanding these can help patients and their care teams better prepare for and manage the unique challenges associated with each treatment modality.

Immune Checkpoint Inhibitors:

These drugs work by blocking proteins that prevent the immune system from attacking cancer cells. Common side effects include:

• Skin Reactions: Rash, itchiness, and vitiligo.

• Gastrointestinal Issues: Diarrhea and colitis.

• Liver Problems: Hepatitis and increased liver enzymes.

• Endocrine Disorders: Hypothyroidism, hyperthyroidism, and adrenal insufficiency.

Monoclonal Antibodies:

These lab-made molecules mimic the immune system’s ability to fight harmful pathogens. Side effects may include:

• Infusion Reactions: Fever, chills, and low blood pressure during administration.

• Skin Reactions: Rash and itchiness.

• Cardiovascular Issues: High blood pressure and heart-related problems.

• Gastrointestinal Issues: Nausea and diarrhea.

CAR T-Cell Therapies:

This therapy involves modifying a patient’s T-cells to attack cancer cells more effectively. Possible side effects include:

• Cytokine Release Syndrome (CRS): Fever, low blood pressure, and difficulty breathing.

• Neurological Problems: Confusion, seizures, and loss of consciousness.

• Infections: Increased risk of bacterial, viral, and fungal infections.

• B-Cell Aplasia: Low B-cell levels lead to decreased antibodies and increased infection risk.

What Are the Severe Side Effects of Immunotherapy?

While most side effects from immunotherapy are manageable, some can be severe and potentially life-threatening. Severe immunotherapy side effects include:

• Inflammation-Related Issues: Such as myocarditis (heart inflammation), pneumonitis (lung inflammation), and hepatitis (liver inflammation).

• Neurological Complications: Rare but serious effects like meningitis or encephalitis can occur.

• Autoimmune Reactions: Including conditions like type 1 diabetes or severe arthritis.

Immediately consult with your medical team if you experience any severe side effects.

How Are Immunotherapy Side Effects Treated or Managed?

Immunotherapy side effects are managed through prompt symptom reporting, immunosuppressive medications like steroids, regular monitoring, and, in some cases, temporary or permanent discontinuation of treatment. 

Effective management strategies tailored to specific side effects help maintain quality of life during immunotherapy. There are immunotherapy management options that are easy to implement at home and may include :

• Fatigue: Manage fatigue by taking short, 15-20 minute naps and engaging in light exercise like walking, which can boost energy levels. Maintain hydration by drinking 8-10 glasses of non-caffeinated liquids daily.

• Diarrhea and Immune-Related Colitis: Monitor bowel movements and consult your healthcare provider if changes occur. Avoid spicy, high-fiber, or high-fat foods. Hydrate with water and electrolyte-rich liquids.

• Mucositis: Manage mouth sores by using alcohol-free mouthwash, keeping lips moisturized, and eating non-irritating foods. Consult your healthcare provider about oral cryotherapy.
• Neuropathy: Manage numbness or tingling through regular exercise, avoiding alcohol, and wearing protective clothing. Consider acupuncture and consult your healthcare provider if symptoms worsen.

• Skin Changes: Keep skin moisturized, avoid direct sunlight, and use high-SPF sunscreen. Wear protective clothing and consult your healthcare provider if skin conditions like rash or peeling occur.

Real Patient Experiences

Understanding the experiences of others who have undergone immunotherapy and navigated the side effects can provide invaluable insights and a sense of community. Each story highlights both the challenges and the triumphs of cancer immunotherapy treatment.

• Explore Patient Stories: Delve into the stories of patients who have faced similar battles. These accounts shed light on potential side effects and illustrate the resilience and courage of individuals navigating their treatment journeys.

• Join the Community: Connect with others in the immunotherapy patient community through discussion forums, support groups, and CRI patient summits. Share experiences, ask questions, and receive support from peers who understand what you’re going through.

• Participate in Clinical Trials: Explore clinical trials that offer access to new therapies and strategies. CRI provides access to these trials, bringing us closer to a world immune to cancer.

CRI’s Commitment to Immunotherapy Research

At CRI, we ensure patients are well-informed and equipped to handle their treatment. Our commitment extends beyond research, we provide resources and support for navigating the complexities of immunotherapy.

Your support can accelerate groundbreaking research and provide critical resources for patients. Donate today to help create a world immune to cancer.

Always remember to consult your medical team for any concerns or questions regarding your treatment.

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Frequently asked questions

How soon and how often should I expect to experience immunotherapy side effects?

There is no set window of time during which patients might experience side effects from immunotherapy. Some immunotherapy side effects, such as infusion-related reactions or injection site pain, can occur shortly after treatment is administered. However, because immunotherapy treatments can take time to “kick in” and impact immune cell activity, most side effects may not occur until weeks or months or longer after treatment.

As with time of onset, there is no standard frequency with respect to how often immunotherapy side effects occur, although frequency may depend on a particular patient’s treatment regimen (i.e., how often and how many treatments they receive). In general, the earlier side effects are reported and addressed, the better the chance that the side effects can be effectively managed in order to lessen their frequency and duration and minimize potential pain, discomfort, or damage. The likelihood of side effects is higher with combination immune therapies than single agents.

What symptoms should I look out for?

Some of the most common side effects associated with immunotherapy treatment may include but are not limited to: chills, constipation, coughing, decreased appetite, diarrhea, fatigue, fever and flu-like symptoms, headache, infusion-related reaction or injection site pain, itching, localized rashes and/or blisters, nausea, rash, shortness of breath, vomiting, and weight loss.

If you experience any of these side effects, or any unusual changes to your health, you should notify your healthcare team as soon as possible.

How long do immunotherapy side effects last?

The long-term side effects of immunotherapy vary from patient to patient. While the majority of immunotherapy side effects often can be temporary and reversible, some of side effects may persist after treatment because immunotherapy can influence the activity of immune cells that remain in the body long after the drug has been cleared from the patient’s system. In rare cases, the consequences of immunotherapy side effects may be permanent.

How are immunotherapy side effects treated or managed?

Depending on the treatment, immunotherapy side effects can be treated in a number of ways. For example, patients may be taken off treatment, either temporarily or permanently, in order to allow the immune activity to quiet down. Additionally, especially with checkpoint inhibitor immunotherapies, patients may receive steroids or immunosuppressive antibodies as a more active measure in order to dampen immune activity and minimize potential damage from any further autoimmune reactions.

In the case of the cytokine release syndrome (or cytokine storm), among potential CAR T cell therapy side effects, doctors may administer drugs to block the activity of certain cytokine signaling pathways, such as interleukin-1 (IL-1) or interleukin-6 (IL-6).

In general, many of immunotherapy’s potential side effects can be managed with early intervention. Therefore, it is important for patients to report any adverse changes in their health or overall well-being to their healthcare team as soon as they are aware of them.

Do side effects mean the immunotherapy is working?

More work still needs to be done to definitively answer this important question, although some recent studies have found that patients who experience low-grade side effects after immunotherapy may be more likely to have better outcomes.

How do doctors monitor side effects?

There are a number of ways for doctors to monitor side effects. Patients, however, will often be aware of changes in their own bodies before their doctors have a chance to monitor and detect any side effects. It therefore is important for patients to report any adverse changes in their health or overall well-being to their healthcare team as soon as they are aware of them.

When should I inform my doctor of side effects?

Patients should notify their doctors as soon as they can if they experience any noticeable changes in their external body appearance, their health, or their overall physiological state after being treated with immunotherapy. The earlier side effects are reported and addressed, the better the chance that they can be effectively managed in order to minimize potential pain, discomfort, or damage.

Should I speak with patients who have been treated with immunotherapy about their side effects?

Cancer patients often help inform their fellow patients about their experiences. Gain a different perspective on side effects from patients who have been treated with various immunotherapies and discover how they managed side effects.

Reviewer: Jeffrey S. Weber, MD, PhD, NYU Langone Health

Sources: U.S. Food and Drug Administration (FDA) Online Label Repository; National Cancer Institute (Hormone Therapy); National Cancer Institute (Stem Cell Transplant)

Updated November 2019

*Immunotherapy results may vary from patient to patient. Consult a healthcare professional about your treatment options.

Related Links

What is Immunotherapy

Immunotherapy Treatment Types

Immunotherapy by Cancer Type

Immunotherapy Stories

Understanding Clinical Trials

Immunotherapy Webinars