Truxima side effects: what they are and how to manage them

If you're starting Truxima (rituximababbs) and feeling that mix of hope and worryespecially about side effectsyou're not alone. I've sat in infusion chairs, asked the same anxious questions, and learned that preparation is power. Here's the short version: most people have mild, manageable reactions; a smaller number can have serious ones that need quick care. Knowing the difference helps you breathe easier.

Below, you'll find the most common Truxima side effects, the serious ones to watch for, and practical steps to reduce your risk. My goal is simple: to help you balance benefits and risks, feel confident walking into your infusion, and know exactly when to call for help.

Quick takeaways

Let's start with the basics. The most common Truxima side effects include fatigue, infusion reactions, fever, chills, nausea, rash or itching, and headache. Many of these show up during or after the first infusion and tend to improve with later cycles. Think of it like your body saying, "Whoa, new guest in the house!" before settling in.

Common side effects at a glance: fatigue that makes you want a nap by afternoon; a warm, flushed feeling during infusion; low-grade fevers and chills; a queasy stomach; a mild rash; and a headache. If you've ever had a strong cold and felt washed out, some of these will feel familiar.

When do they show up? Infusion reactions typically appear during the first infusion or within 24 hours after. Later cycles usually go smoother because your care team adjusts the infusion rate and premeds. Fatigue may linger for a couple of days. Nausea and headache tend to be short-lived and respond to simple home care.

What does an infusion reaction feel like? Picture a mix of warm flushing, itchiness, tight throat, mild chest pressure, chills, or dizziness. Often it's mild to moderate and eases when the nurse slows or pauses the infusion and gives extra meds. Most reactions improve within minutes to a few hours.

Mild versus moderate: what's typical? Mild rash, low fever (under about 100.4F/38C), queasiness, and tiredness are common and expected. What's not typical? Worsening shortness of breath, chest tightness, lightheadedness that makes you feel faint, or a fever at or above 100.4F (38C). Those need a call to your care teamsooner rather than later.

Serious risks

Serious Truxima side effects are less common, but they matter. I'm not here to alarm youjust to give you a clear map so you can act fast if needed.

Severe infusion reactions can include trouble breathing, chest pain or pressure, severe dizziness, or swelling of the lips/tongue. If this happens during an infusion, your team will pause the drug, treat you immediately, and monitor closely. If symptoms start later at homeespecially breathing problems or faintingcall emergency services. Don't wait it out.

Infections and low immune response are important because rituximab targets B cells, a crucial part of your immune system. That's the "why" behind increased infection risk. Watch for fever at or above 100.4F (38C), productive cough, painful urination, new rashes or sores, or feeling unusually weak. Prevention helps: hand hygiene, avoiding sick contacts, and staying updated on vaccines (with careful timingmore on that below). Your clinician might recommend certain vaccinations before starting therapy and discuss delaying live vaccines after treatment, in line with guidance such as CDC immunization considerations for immunocompromised people (you may see these referenced in clinical resources or guidelines).

Hepatitis B reactivation is a known risk with rituximab-class therapies. That's why many patients get hepatitis B surface antigen and core antibody testing before the first dose. If you have evidence of past infection, your team may start antiviral medication and check labs during and after treatment. Expect periodic liver function tests too. Reactivation is uncommon when screening and monitoring are done properly, but it's important to respect this risk.

Rare but serious risks include PML (a brain infection called progressive multifocal leukoencephalopathy), severe skin reactions, and cardiac events. PML is very rare but seriouscall immediately if you notice new confusion, vision changes, trouble speaking, weakness, or severe headache. Severe skin reactions can start as widespread rash, blistering, or peeling skin. Cardiac issues might present as chest pain, shortness of breath, or palpitationsespecially if you already have heart disease.

Truxima side effects vs rituximab side effectsany difference? Truxima is a biosimilar to rituximab. Biosimilars are tested extensively to ensure no clinically meaningful differences in safety, purity, and effectiveness compared with the reference product. That means Truxima side effects are expected to be comparable to rituximab side effects across conditions and dosing. This similarity is a key requirement under regulatory approvals (for example, FDA and EMA biosimilar frameworks, as explained in agency guidance and product labeling).

Practical steps

Let's talk about what actually helpsbefore, during, and after your infusion.

Before your infusion: Most centers give premedications such as acetaminophen, an antihistamine (like diphenhydramine), and a corticosteroid. These help reduce infusion reactions and make the day smoother. Share your full medical story: recent infections, vaccine dates, heart or lung issues, hepatitis history, TB exposure, pregnancy plans, and all medications (especially steroids, chemo, methotrexate, or other immunosuppressants). This sets your team up to protect you well.

During your infusion: Nurses monitor your vitals, breathing, and how you're feeling. Don't be shyspeak up if you notice itching, throat tightness, warmth, flushing, dizziness, nausea, chest pressure, or shortness of breath. Often, simply slowing the infusion and giving a bit more antihistamine does the trick. I've seen a nervous first infusion transform into a calm second one just by adjusting the rateyou're not being "difficult" by asking for help; you're being smart.

After your infusion: Plan for a gentle evening. Hydrate. Light meals. Rest. For fatigue, listen to your bodyshort walks and naps can be a great combo. For nausea, small snacks, ginger tea, and prescribed anti-nausea meds help. Headaches usually respond to acetaminophen (if your clinician says it's okay). A mild rash or itch might settle with a cool compress or antihistamine; call your team if it spreads or worsens.

Delayed infusion reactions can occur up to 24 hours later. Keep an eye on fever, chills, breathing changes, or chest discomfort. If you're worried, calleven for reassurance. I'd rather see you over-call than under-call.

Infection prevention while on Truxima: This is where small habits pay off big. Wash hands often. Wear a mask in crowded indoor spaces or high-risk settings, especially during cold and flu season. Be mindful with food safety (avoid undercooked meats, unpasteurized dairy, and wash produce well). Keep dental checkups on schedulegum inflammation can be a sneaky source of infection. Vaccination planning matters: in many cases, vaccines work best before Bcell depletion; inactivated vaccines during treatment may be less effective but can still provide protection. Live vaccines are typically avoided during and for a period after rituximab-class therapy; timing should follow your clinician's guidance and established immunization recommendations for immunocompromised patients (for example, see evidence-based guidance cited in professional society or public health resources). If you're mapping out vaccines around Truxima, it's worth discussing specifics like flu, COVID19, pneumococcal, and shingles (non-live) with your team to maximize benefit.

Tracking side effects: Keep a simple symptom journal. Note the date, time, what you felt, how intense it was (use a 010 scale), any triggers, what you tried, and what helped. This gives your care team real data to tweak premeds, infusion rates, or supportive meds. It also reassures you that patterns are emergingand improving.

Higher risk

Some people need extra precautions. If you have chronic infections, prior hepatitis B, significant heart or lung disease, or a history of severe allergic reactions, your team may order additional tests and monitor you more closely. That might mean baseline EKGs, pulmonary checks, or more frequent labs.

Age and concurrent medications matter too. Older adults can be more susceptible to infection or cardiac stress. Combination therapieslike RCHOP for lymphoma or rituximab with methotrexate for rheumatoid arthritiscan change the side-effect profile and how often your labs are checked. None of this is a stop sign; it's a guide. The right plan lowers risk without losing the benefits.

Benefits vs risks

Why is Truxima used? Because for many people with certain blood cancers and autoimmune diseases, it can be life-changing. In diffuse large Bcell lymphoma, follicular lymphoma, and CLL, it's a backbone medication, often in combination regimens. In autoimmune conditions like rheumatoid arthritis, granulomatosis with polyangiitis, and microscopic polyangiitis, it helps calm the immune system and reduce steroid needs. Clinicians weigh disease control against side-effect risks by looking at your diagnosis, disease activity, other treatments, infection history, and personal preferences. It's not one-size-fits-all; it's tailored.

Shared decision-making is your superpower. Ask: What benefits can I reasonably expect and when? What's my personal infection risk and how will we lower it? What premeds will I get and why? How will we time vaccines? What labs are we checking and how often? Who do I call after hours?

A personalized risk-reduction plan should include screening (HBV, sometimes TB), vaccine planning, infusion premeds, an infusion rate strategy (especially for the first dose), and a lab schedule. If something changessay you develop a cough or new fevertell your team early. They can pause, delay, or adjust treatment as needed.

When to pause, delay, or stop treatment: If you have an active infection, uncontrolled fever, severe infusion reaction, or lab abnormalities (like certain liver or blood count changes), your clinician may hold treatment while addressing the issue. Alternatives existdifferent biologics for autoimmune disease, or modified regimens in oncologybut the choice depends on your condition and goals. This is where a clear, honest conversation really shines.

Treatment areas

Truxima side effects can look a bit different depending on why you're receiving it.

Blood cancers (DLBCL, follicular lymphoma, CLL): When combined with regimens like RCHOP, you may also have side effects from chemotherapynausea, hair loss, lowered blood counts. Infusion reactions are still mostly first-infusion events. Infection vigilance is essential, especially if white counts dip. Your team might give growth factors, prophylactic antibiotics, or antiviral medications depending on your protocol.

Rheumatoid arthritis and other autoimmune diseases: You might notice timing differencessome people feel a "mini-flare" before improvements kick in (often weeks after the last infusion of a cycle). Infection vigilance remains key, especially if you're on steroids or methotrexate. Lab monitoring helps catch issues early.

Granulomatosis with polyangiitis and microscopic polyangiitis: The goal often includes reducing steroid exposure while keeping disease quiet. Monitoring might include kidney function, urinalysis, and markers of inflammation. If you're on prophylactic meds (like for Pneumocystis pneumonia), take them as directed.

How it works

How does Truxima cause both benefits and side effects? One phrase: Bcell depletion. Truxima targets CD20 on B cells, reducing their numbers. In cancers that rely on B cells or in autoimmune diseases driven by Bcell activity, that's exactly what we want. But fewer B cells can also mean a blunted immune response, which explains the infection risk and vaccine timing dance. Over months, B cells typically recover, and your team may time retreatment based on disease activity and lab results.

Biosimilar vs reference rituximab: Truxima is designed to match rituximab closely, with rigorous testing to confirm similar safety and effectiveness. Regulatory approvals require robust evidenceanalytical comparisons, clinical studies, and pharmacovigilanceshowing comparable side effect profiles. If you've been on rituximab before, switching to a biosimilar like Truxima generally shouldn't change how you feel or respond, according to data used in approvals and real-world experience.

Call or ER?

When should you call your care team within 24 hours? Worsening rash, persistent fever under 100.4F (38C), nausea that's not improving with your meds, or mild new breathing changes (like a cough that's getting tighter). If you're unsure, call. That's what they're there for.

When should you seek urgent or emergency care? Trouble breathing, chest pain, severe dizziness or fainting, high fever at or above 100.4F (38C), confusion, severe headache, new weakness, vision changes, or yellowing of the skin/eyes. If a symptom feels scary or sudden, trust your instincts and get help.

Helpful context

If you love diving deeper into the "why," it's worth knowing that much of what we recommendlike HBV screening and vaccine timingcomes from clinical trial data, drug labeling, and professional guidelines. For example, antiviral prophylaxis for patients with prior hepatitis B exposure is a common, evidence-based approach in rituximab-class therapy, and vaccine timing for people receiving Bcell depleting agents is guided by immunization frameworks for immunocompromised patients (summaries can be found in public health and specialty society resources). According to an FDA overview of biosimilars and product labeling for rituximab products, side effect profiles for biosimilars like Truxima are expected to be comparable to the reference product, and this is reflected in approvals and post-marketing data. If you're curious, you can explore an accessible explanation of biosimilar standards in agency resources through biosimilar product information, or read clinical guidance summaries on immunization considerations for immunocompromised patients via public health authorities and professional societies.

A quick story

I once spoke with a patient who described her first infusion as a "roller coaster that started too fast." She felt flushed and light-headed within 30 minutes. The nurses paused the drip, gave an extra antihistamine, and restarted at a slower rate. The rest of the day? Quiet. Her second infusion? Uneventful. Her takeawayand now minewas simple: communicate early, adjust quickly, and trust the process. Your team has seen this before and knows how to steer.

Gentle next steps

Here's a simple checklist you can use today: confirm your HBV screening; ask about vaccine timing; write down your premeds and when to take them; pack comfort items for infusion day (water bottle, snacks, a good podcast); set up a symptom journal; and save your clinic's after-hours number in your phone. Small steps, big peace of mind.

What do you think about this plan? Does it feel manageable? If you've been through Truxima before, what helped mostextra premeds, a slower rate, or planning quiet time afterward? Share your experiences and any tips you wish you'd heard sooner.

Closing thoughts

Truxima can bring real relief and controlespecially for certain blood cancers and autoimmune diseasesbut it also carries risks that deserve respect. Most Truxima side effects are mild and manageable with premeds, a slower infusion rate, and simple home care. A smaller set can be serious, and knowing the early warning signs is the best way to stay safe. Keep an open line with your care team, track your symptoms, and ask about screenings and vaccines before you start. If something feels offespecially breathing issues, high fever, or sudden confusionseek urgent help. With a clear plan, you can balance benefits and risks and move through treatment with more confidence. You've got this, and you're not doing it alone.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.