If you’ve just been told you’re starting Gazyva, you’re probably feeling a mix of
“let’s beat this thing” and “wait… what’s going to happen to my body?” Totally normal.
Gazyva (obinutuzumab) is a powerful cancer and immune therapy drug, and with power
comes the possibility of some pretty noticeable side effects. The good news: you and
your care team can plan ahead so most side effects are monitored, managed, andwhen
possiblereduced.

This guide walks you through the most common Gazyva side effects, the serious ones
you really need to watch for, and practical steps you can take before, during, and
after treatment to stay as safe and comfortable as possible.

What Is Gazyva and How Does It Work?

Gazyva (brand name for obinutuzumab) is a monoclonal antibody
that targets a protein called CD20 on certain B cells (a type of white blood cell).
By attaching to those cells, it marks them for destruction by your immune system. That
helps treat conditions where these B cells are part of the problem, including:

• Chronic lymphocytic leukemia (CLL)
• Follicular lymphoma and other types of non-Hodgkin lymphoma
• Active lupus nephritis in some adults (in combination with other lupus medicines)

Gazyva is given by intravenous (IV) infusion in a clinic or hospital,
usually alongside other drugs like chlorambucil or bendamustine for blood cancers, or
with standard lupus treatments.

Why does Gazyva cause side effects?

Gazyva doesn’t just quietly slide into your bloodstream. When it starts attacking B cells,
your immune system often reacts. That immune responseplus changes in blood counts and how
your organs handle treatmentcan lead to side effects ranging from mild fatigue to serious
infusion reactions.

Many side effects happen early, especially with the first few infusions. Others show up
later as your blood counts drop or as your immune system stays suppressed.

Common Gazyva Side Effects

Not everyone has the same experience, but certain side effects show up a lot in clinical
trials and real-world use. The most common include:

• Infusion-related reactions (especially with the first dose)
• Low white blood cells (neutropenia)
• Low platelets (thrombocytopenia)
• Low red blood cells (anemia)
• Fever and chills
• Diarrhea or constipation
• Fatigue
• Cough or respiratory infections
• Rash or itching

These side effects were reported frequently in clinical trials and patient safety
summaries from the manufacturer and large drug information sites.

Infusion-related reactions

Infusion-related reactions (IRRs) are the big ones. They usually happen
during or within 24 hours of an infusionoften the very first day
of treatment. Signs of an infusion reaction can include:

• Fever, chills, or feeling suddenly “flu-ish”
• Headache
• Flushing, rash, or itching
• Shortness of breath, cough, or chest tightness
• Dizziness, lightheadedness, or fainting
• Fast heartbeat

In studies, the majority of people with CLL had some degree of reaction during the first
big dose of Gazyva. That’s why the drug is started slowly and why premedications
(like acetaminophen, antihistamines, and steroids) are standard.

What you can do: Tell your nurse immediately if you feel
“off” during an infusioneven if it seems minor. Most reactions can be controlled by
slowing or briefly stopping the infusion and giving extra medications.

Blood cell changes

Because Gazyva targets B cells and can affect the bone marrow, it can lower different
types of blood cells:

• Neutropenia (low neutrophils): Raises the risk of infection. You
  might not feel anything until you get a fever, chills, sore throat, or other infection
  symptoms.
• Thrombocytopenia (low platelets): Makes bleeding and bruising more
  likelythink nosebleeds, bleeding gums, or tiny red dots on the skin (petechiae).
• Anemia (low red blood cells): Can cause fatigue, shortness of breath,
  dizziness, and paleness.

Blood count changes are among the most common lab abnormalities seen with Gazyva,
so regular blood tests are part of the deal.

What you can do: Go to all scheduled lab checks, report new bruising
or bleeding, and call if you develop a fever (often defined as 100.4°F / 38°C or higher
in people on cancer therapyyour team will give you a specific threshold).

Infections

By knocking down certain immune cells, Gazyva can raise your risk of infections,
including respiratory infections (like bronchitis or pneumonia), urinary tract infections,
and more serious systemic infections.

What you can do:

• Wash your hands often and avoid close contact with sick people when possible.
• Call your doctor promptly for fevers, chills, cough, or burning with urination.
• Ask your team which vaccines are recommended or should be avoided during treatment.

Digestive and general symptoms

Many people on Gazyva report diarrhea, constipation, nausea, decreased appetite,
and fatigue. These are rarely dangerous by themselves but can wear you down
over multiple cycles.

What you can do: Ask about anti-nausea meds, sip fluids frequently,
eat small, frequent meals, and let your team know if diarrhea or constipation becomes
severe or lasts more than a couple of days.

Serious and Long-Term Side Effects

There are several rare but serious side effects with Gazyva that deserve special
attention. Two of them are so important they appear in an FDA boxed warning
(sometimes called a “black box warning”) on the drug label.

Hepatitis B reactivation (boxed warning)

If you’ve ever had hepatitis Bor even been exposed in the pastthe virus can go
“sleepy” and hang out in the liver. Gazyva and other anti-CD20 drugs can wake it back
up, causing hepatitis B reactivation. In severe cases, that can lead
to liver failure or death.

What you can do:

• Make sure your team knows your full hepatitis history, including any past infections.
• Expect blood tests for hepatitis B before starting Gazyva.
• If you’re at risk or test positive, your doctor may prescribe antiviral medicine and monitor your liver closely.
• Report symptoms like yellowing of the skin or eyes, dark urine, right-sided belly pain, or severe fatigue right away.

Progressive multifocal leukoencephalopathy (PML)

PML is a rare but very serious brain infection caused by reactivation of the JC virus.
It can cause permanent disability or be fatal. Gazyva carries a boxed warning for a small
but real risk of PML, similar to some other powerful immune-modifying drugs.

Symptoms of PML may include:

• Vision changes or loss
• Weakness in the arms or legs
• Difficulty speaking or understanding language
• Clumsiness, poor coordination, or personality changes

What you can do: Contact your doctor right away if you or your family
notice new neurological symptoms. Do not try to “wait it out.”

Tumor lysis syndrome (TLS)

Tumor lysis syndrome happens when cancer cells die off very quickly, releasing their
contents into the bloodstream. This can overwhelm the kidneys and affect your heart
and electrolytes. TLS is more common in people with a large tumor burden or very
fast-growing cancers.

What you can do: Your team may give preventive medicines and extra
fluids, especially early in treatment. Call immediately for sudden decreased urine,
swelling, rapid weight gain, or severe back or side pain.

Severe allergic reactions

While many infusion reactions are mild to moderate, a small number of people can have
severe allergic reactions, including anaphylaxis or serum sickness,
which affect multiple body systems.

Signs of a severe reaction may include:

• Swelling of the face, lips, tongue, or throat
• Trouble breathing or wheezing
• Severe dizziness or fainting
• High fever, hives, or a widespread rash

These are emergencies. If symptoms happen outside of the infusion center, call
911 or your local emergency number.

Other serious problems

Less commonly, Gazyva can be associated with:

• Serious infections (including pneumonia or sepsis)
• Severe low blood counts requiring hospitalization or growth factor support
• Heart or lung complications related to infusions

Your healthcare team balances these risks against the potential benefits of controlling
your cancer or autoimmune disease.

What to Do About Gazyva Side Effects

Before you start treatment

Front-loading the planning can make treatment smoother. Before your first infusion,
your team will typically:

• Review your full medical history, including previous infections and liver disease
• Screen for hepatitis B and other infections
• Check baseline blood counts and kidney and liver function
• Discuss other drugs you’re taking, including supplements and over-the-counter meds

This is your chance to ask about fertility, pregnancy and breastfeeding precautions,
vaccines, and how treatment may affect work or family life.

During your Gazyva infusions

On infusion days, your team will give premedications and start the IV slowly, watching
closely for reactionsespecially during that first long day. You can help by:

• Reporting any new symptoms right away (even if they seem minor)
• Bringing a list of your current medicines and any recent changes
• Staying well-hydrated unless your doctor has told you to limit fluids

If a reaction happens, the infusion can be paused or slowed, and extra medicines
can be added. Most people are able to continue treatment after adjustments.

Between cycles: home care and monitoring

Once you leave the clinic, you’re still part of the care team. Keep track of how you
feel and watch for warning signs such as:

• Fever or chills
• New or worsening cough, shortness of breath, or chest pain
• Unusual bruising, bleeding, or tiny red spots on the skin
• Severe fatigue, dizziness, or paleness
• Persistent diarrhea, vomiting, or inability to keep fluids down
• Yellowing of the skin or eyes, very dark urine, or right-sided belly pain
• Any sudden changes in vision, balance, strength, or speech

Keep a small notebook or notes on your phone that you can quickly share at your next visit.
Patterns (like fatigue that hits two days after each infusion) can be very helpful in
adjusting your care.

When to call your doctor vs. the emergency room

General guidance (your doctor may give more specific rules):

• Call your care team promptly for new or worsening non-emergency
  symptoms: mild rash, mild diarrhea, moderate fatigue, early signs of infection,
  mild nausea, or questions about your medications.
• Seek emergency care (call 911 or your local emergency number) for:
  severe trouble breathing, chest pain, severe allergic reaction symptoms, high fever
  with shaking chills, confusion, seizure, or signs of stroke or PML.

Never stop Gazyva or other cancer medications on your own without talking to your
oncologist or specialist.

Smart Questions to Ask Your Healthcare Team

• “What are my biggest risks for side effects based on my health and labs?”
• “How will you monitor my liver, kidneys, and blood counts?”
• “What symptoms should trigger an immediate phone call or urgent visit?”
• “Are there lifestyle steps I can take to lower my infection risk?”
• “If I react badly to the first infusion, can the schedule or dose be adjusted?”
• “How long after finishing Gazyva do I need to keep watching for delayed side effects?”

Having these conversations up front can make you feel less like a passenger and more
like a co-pilot in your care.

Real-World Experiences: Living With Gazyva Side Effects

Everyone’s Gazyva journey is different, but some themes come up again and again when
people share their experiences with side effects.

The first infusion: “I felt like I had the flu in a recliner”

Many people say the first Gazyva infusion is the roughest. The infusion is long, the
premeds can make you sleepy, and infusion-related reactions can feel like being hit
with a fast-moving fluchills, fever, tight chest, maybe some shortness of breath.
The upside? The team is watching you like a hawk. If you start to feel strange, you
say something, they slow the drip, add meds, and most reactions settle down.

A lot of patients describe the second and third infusions as noticeably easier.
By then, the care team knows how your body tends to respond and can adjust the
premedication plan to blunt reactions.

Fatigue: the sneaky side effect

Fatigue from Gazyva is rarely dramatic in a “can’t get out of bed for weeks” way,
but more of a steady drag. You might feel pretty normal on infusion day thanks to
steroids, then hit a wall a day or two later. Many people learn to plan “low-power
days” after infusions: fewer errands, lighter chores, more naps, and no guilt.

Simple strategies help: prepping meals in advance, asking friends or family to
handle rides or grocery runs right after infusion days, and breaking tasks into
small chunks with plenty of breaks.

Blood counts and “germ-avoidance mode”

When neutrophils drop, your team may refer to it as being “neutropenic.” That’s cue
for extra caution around infection. People often get creative: keeping hand sanitizer
in every bag, masking in crowded indoor spaces, skipping that one friend who “always
has a cold,” and calling the doctor early for fevers instead of waiting.

Some patients need growth-factor injections to boost white blood cells or transfusions
for anemia or low platelets. While that can feel intimidating at first, many people
come to see these as temporary tools that support them through treatment rather than
signs that therapy is failing.

Emotional side effects are real too

Worrying about serious things like hepatitis B reactivation, PML, or severe infections
can be emotionally draining. It’s common to check every little symptom and wonder if
it’s something dangerous. Over time, many patients find a balance between staying
vigilant and living their life.

Helpful approaches include:

• Keeping a written plan: “If X happens, I call this number; if Y happens, I go to the ER.”
• Bringing a partner, friend, or relative to visits to help ask questions and remember answers.
• Talking with support groups (online or local) for people on similar treatments.
• Asking for a referral to counseling if anxiety or low mood becomes overwhelming.

Balancing risk and benefit

For most people, Gazyva is not given casuallyit’s chosen because your care team
believes the chance of controlling the disease outweighs the risks. Many patients
who’ve completed treatment describe a sense of relief that the intense monitoring,
blood draws, and infusion days led to real results: smaller lymph nodes, improved
kidney function in lupus nephritis, fewer infections from abnormal blood cells, or
scans that finally show no active disease.

The key takeaway from their experience: side effects are important, but you don’t
have to navigate them alone. The more openly you communicate with your healthcare
team, the better they can adjust your plan to fit your body and your life.

Bottom Line

Gazyva is a strong targeted therapy that can offer major benefits in CLL, follicular
lymphoma, and lupus nephritisbut it carries a range of potential side effects, from
common infusion reactions and fatigue to rare but serious risks like hepatitis B
reactivation and PML. Understanding what to expect, knowing the red-flag symptoms,
and having a clear action plan with your care team can turn a scary-sounding
medication into a carefully managed part of your treatment strategy.

This article is for general education only and is not a substitute
for medical advice. Always talk with your doctor or specialist about how Gazyva side
effects apply to your specific situation and what to do if they appear.

The post Gazyva: Side Effects and What to Do About Them appeared first on Global Travel Notes.