Side Effect: Flu-Like Symptoms

Flu-like symptoms are a set of clinical manifestations that resemble those of a viral infection from influenza (flu). These symptoms can be seen in patients with cancer due to their malignancy or as a medication side effect and resemble having the flu, even though they are not infected with the influenza virus.

The presentation of flu-like symptoms can vary depending on the individual. The onset of flu symptoms can be sudden or gradual, and they can range from mild to severe. These symptoms may include fever, fatigue, weakness, body aches, headache, chills, and shivering.

Patients with Hodgkin lymphoma, certain types of non-Hodgkin lymphoma, and kidney cancer can experience flu-like symptoms due to these diseases. These symptoms are part of what is commonly referred to as “B-symptoms” or “constitutional symptoms”. B-symptoms include: fever, unintentional weight loss, and drenching night sweats.

Certain medications used to treat cancer can also cause flu-like symptoms. Some examples include:

• Bicalutamide (Casodex®)
• Leuprolide (Lupron®)
• Goserelin (Zoladex®)
• Interferon alpha-2b (Intron®)
• Peginterferon alfa-2a (Pegasys®)
• Aldesleukin (Proleukin®)

• Management of flu-like symptoms that are directly related to cancer revolves around treating the underlying cancer itself.
• Lymphomas that cause B-symptoms can respond quickly to aggressive treatment and resolve symptoms in a short period of time.
• If symptoms are a side effect of treatment, supportive care medications such as NSAIDs like ibuprofen (Advil®, Motrin®) or naproxen (Aleve®), acetaminophen (Tylenol®), or corticosteroids can help alleviate some flu-like symptoms, but talk with your doctor before starting any of these medications to make sure it is safe.
• Severe symptoms may necessitate holding treatment of the offending medication, decreasing the dose, or stopping the treatment permanently.