Side Effects of Keytruda

keytruda and its side effects

Are you considering Keytruda as a treatment option? Before you make a decision, it's important to be aware of the potential side effects. Keytruda, like any medication, can cause various reactions in your body. This article will provide you with an objective and detailed overview of the common side effects associated with Keytruda, including gastrointestinal issues, skin and hair reactions, immune system-related complications, respiratory problems, and neurological effects. Stay informed to make the best decision for your health.

Gastrointestinal Side Effects

You may experience gastrointestinal side effects while taking Keytruda. These side effects can include diarrhea, which can be uncomfortable and disruptive to your daily life. It is important to understand that Keytruda works by activating your immune system to fight cancer cells, but this activation can also affect healthy cells in your gut. The gut microbiome, which is a complex community of microorganisms in your digestive tract, plays a crucial role in maintaining a healthy gut. When the balance of this microbiome is disrupted, it can lead to diarrhea. If you experience diarrhea while taking Keytruda, your healthcare provider may recommend certain treatments to help manage this side effect, such as medication or dietary changes. It is important to communicate any side effects you experience with your healthcare provider so they can provide appropriate support and guidance.

Skin and Hair Reactions

Continuing from the previous discussion on gastrointestinal side effects, it is important to be aware of potential skin and hair reactions while taking Keytruda. These side effects can vary in severity and may have an impact on your quality of life. Here are three important things to know:

  1. Allergic reactions: Keytruda can sometimes cause allergic reactions, such as itching, rash, or hives. If you experience any of these symptoms, it is crucial to seek medical attention immediately.
  2. Skin changes: Some patients may notice changes in their skin, such as dryness, redness, or discoloration. It is essential to keep your healthcare provider informed about any skin changes you observe.
  3. Hair loss: While uncommon, Keytruda may cause hair loss or thinning. This can be distressing for some individuals, but it is usually temporary and reversible once the treatment is completed.

Being aware of these potential skin and hair reactions can help you monitor your health and discuss any concerns with your healthcare team.

Immune System Related Side Effects

Moving on to immune system related side effects, it is important to be aware of how Keytruda can impact your body's defense mechanisms. Keytruda works by stimulating your immune system to attack cancer cells. While this can be beneficial in fighting cancer, it can also lead to immune system overactivation and the development of autoimmune disorders. These side effects occur when your immune system mistakenly attacks healthy cells and tissues in your body.

Below is a table summarizing some immune system related side effects that can occur with Keytruda treatment:

Side EffectSymptomsTreatment
ColitisDiarrhea, abdominal pain, blood in stoolImmune-suppressing medications
HypothyroidismFatigue, weight gain, sensitivity to coldHormone replacement therapy
PneumonitisShortness of breath, cough, chest painSteroids
HepatitisYellowing of the skin, abdominal pain, fatigueImmune-suppressing medications
NephritisSwelling of the legs, blood in urine, high blood pressureImmune-suppressing medications

If you experience any of these symptoms or suspect an immune system related side effect, it is important to consult your healthcare provider for proper evaluation and management. They will be able to determine the best course of action to address these issues and ensure your overall well-being.

Respiratory Complications

Respiratory complications can arise as a result of Keytruda treatment. While Keytruda has shown promising results in treating various types of cancer, it is important to be aware of potential side effects that may occur. One of these complications is acute pneumonitis, which refers to the inflammation of the lungs. This can cause symptoms such as coughing, shortness of breath, and chest pain. In some cases, Keytruda can also lead to lung inflammation and damage, which can further exacerbate respiratory problems. It is crucial to monitor any changes in your breathing or lung function while undergoing Keytruda treatment and report them to your healthcare provider immediately. Remember, early detection and intervention can help manage these respiratory complications effectively and ensure your overall well-being throughout your cancer treatment journey.

Neurological Effects

One common neurological effect of Keytruda treatment is the occurrence of peripheral neuropathy. Peripheral neuropathy refers to damage or dysfunction of the nerves that transmit information between the central nervous system and the rest of the body. This can lead to symptoms such as tingling, numbness, weakness, and pain in the hands and feet. While peripheral neuropathy is a known side effect of Keytruda, it is important to note that it is relatively rare. Other neurological effects that have been reported include headaches and dizziness. If you experience any of these symptoms during Keytruda treatment, it is crucial to inform your healthcare provider immediately. They can assess the severity of the symptoms and provide appropriate management strategies to alleviate any discomfort or potential complications.


In conclusion, Keytruda can potentially cause various side effects. Gastrointestinal issues such as diarrhea and nausea may occur, along with skin and hair reactions like rash and hair loss. Immune system-related side effects, such as thyroid problems and inflammation, are also possible. Respiratory complications and neurological effects like headache and dizziness may occur as well. It is important to be aware of these potential side effects and consult with healthcare professionals if any concerns arise during Keytruda treatment.