- Prescribing Information
- For US Patients
DARZALEX® side effects
Side effects
A side effect is an unwanted or unexpected reaction to a drug. Tell a member of your healthcare team if you have any side effect that bothers you or that does not go away.
The most common side effects of DARZALEX® include cold-like symptoms (upper respiratory infection); diarrhea; constipation; decreased red blood cells; nerve damage causing tingling, numbness, or pain; tiredness; swollen hands, ankles, or feet; nausea; cough; fever; shortness of breath; feeling weak.
Infusion Reactions
Infusion reactions are common with DARZALEX® and can be severe. About half the people treated with DARZALEX® experience an infusion reaction. This is most likely to happen during the first infusion and less likely with future infusions. A healthcare professional will monitor you during every DARZALEX® infusion.
If you do have an infusion reaction, your healthcare professional may temporarily stop your infusion or completely stop treatment with DARZALEX®.
Infusion reaction symptoms may include:
- shortness of breath or trouble breathing
- dizziness or lightheadedness (hypotension)
- cough
- wheezing
- heart beating faster than usual
- low oxygen in the blood (hypoxia)
- throat tightness or irritation
- runny or stuffy nose
- headache
- itching
- high blood pressure
- eye pain
- nausea
- vomiting
- chills
- fever
- chest discomfort
- or blurred vision
DARZALEX® can also cause:

Changes in blood tests
DARZALEX® can affect the results of blood tests to match your blood type. These changes can last for up to 6 months after your final dose of DARZALEX®. Your healthcare provider will do blood tests to match your blood type before you start treatment with DARZALEX®. Tell all of your healthcare providers that you are being treated with DARZALEX® before receiving blood transfusions.

Decreases in blood cell counts
DARZALEX® can decrease white blood cell counts, which help fight infections, and blood cells called platelets, which help to clot blood. Decreases in blood cell counts are common with DARZALEX® but can be severe. Your healthcare provider will check your blood cell counts during treatment with DARZALEX®. Tell your healthcare professionals if you develop fever or have signs of bruising or bleeding.
Questions to ask before and after treatment
Here are a few things you may want to ask your doctor so you can be better prepared for treatment with DARZALEX®:
- What side effects should I watch for?
- Do I need to make any changes to my diet during or after treatment?
- What kind of exercise can or should I do while being treated?
- What type of follow-up will I need after treatment and when?
- How will we know if the cancer has come back? What should I watch for?
Generate your own list of questions with our Personalized Doctor Conversation Starter