Nursing care
Monoclonal antibody infusions: infusion reactions, rate control and infection risk
Written and reviewed by Dana Whitfield, RN, MSN · 4 min read · Updated October 2026
Short answer
Monoclonal antibodies, the drugs ending in -mab, share a nursing pattern: confirm ordered infection screening such as hepatitis B or tuberculosis tests, give premedication on time, start the infusion slowly and titrate only per protocol, and watch closely for infusion reactions. Stop and escalate for wheeze, hypotension, hypoxia or angioedema, and teach infection precautions.
What the -mab suffix tells the nurse
Monoclonal antibodies are laboratory-made immune proteins designed to recognise one specific target, and their generic names end in -mab. Rituximab, for example, binds CD20 on B cells and marks them for destruction, while infliximab blocks tumour necrosis factor. Because they are proteins, most are given by infusion or injection rather than by mouth.
The targets differ widely, so indications range from lymphoma to Crohn's disease, but the nursing pattern repeats. Any -mab can provoke a reaction while it runs, and many weaken part of the immune response. Check the specific drug's label and local protocol for details, then apply the shared approach: screen, premedicate as ordered, start slowly, watch closely and teach.
Before the infusion: screening and premedication
Screening targets infections these drugs can unmask. The rituximab label warns of hepatitis B reactivation, including in people whose infection appeared resolved, and the infliximab label calls for testing for latent tuberculosis before treatment. Confirm ordered results are documented, ask about current fever or infection, and check vaccination plans, because live vaccines are not recommended around rituximab treatment. Document any previous infusion reaction clearly, because it shapes premedication and the starting rate.
Premedication is ordered to blunt infusion reactions. For rituximab, the label calls for an antihistamine and acetaminophen before each dose, with a glucocorticoid added for some indications. Give premedications at the ordered time, record baseline vital signs and oxygen saturation, and confirm emergency drugs and oxygen are within reach before hanging the bag. Rituximab must not be given as an intravenous push or bolus.
Recognising an infusion reaction and controlling the rate
Reactions cluster around the first infusion. With rituximab, severe reactions typically began 30 to 120 minutes into the first dose and included urticaria, hypotension, angioedema, hypoxia and bronchospasm. The National Cancer Institute also describes flu-like symptoms such as chills, fever and aches, and cytokine release syndrome, which can bring fever, rapid heartbeat, low blood pressure and trouble breathing.
Rate is the nurse's main lever. Start at the ordered rate and increase only on the protocol schedule while vital signs stay stable. If a reaction begins, interrupt or slow the infusion as directed, stay with the patient, keep the line open and notify the prescriber. The rituximab label allows restarting at half the previous rate once symptoms improve, on the prescriber's decision.
When to stop the infusion: a worked example
Stop the infusion and call for help at once for signs of a severe reaction: throat or tongue swelling, wheeze, falling blood pressure, falling oxygen saturation or chest pain. Management may include epinephrine, glucocorticoids, bronchodilators and oxygen under the emergency protocol. Patients with heart or lung disease need closer watching, because rituximab reactions have included arrhythmias and myocardial infarction.
Consider a hypothetical patient twenty minutes into a first rituximab infusion who develops chills, flushing and new wheeze, with oxygen saturation drifting down. Options include giving acetaminophen and continuing, increasing the rate to finish sooner, or stopping the infusion and assessing airway and breathing. Stopping and assessing is correct, because wheeze with falling saturation signals a respiratory reaction rather than routine discomfort.
Teaching after the infusion and handover
Fatal rituximab reactions have occurred within 24 hours of the infusion, so teaching continues after the bag is finished. Ask the patient to report fever, chills, breathing difficulty, rash or swelling after going home, and to seek emergency care for throat tightness or collapse. Infections and delayed skin reactions may surface days or weeks later.
Because many -mabs suppress immune defence, teach hand hygiene, avoiding people with active infections and reporting fever, cough or new rash promptly. Ask the patient to tell every clinician, including the dentist, about the treatment, and to check before any vaccine. Hand over the time of the dose and any reaction so the next team can plan premedication and rate.
Sources and further reading
DailyMed: Rituxan (rituximab) injection prescribing information. Boxed warning for fatal infusion reactions mostly with first infusion, onset timing, premedication, no IV push, interrupting and halving the rate, hepatitis B reactivation and live vaccine advice.
DailyMed: Infliximab injection prescribing information. Boxed warning for serious infections including tuberculosis and testing for latent tuberculosis before treatment.
National Cancer Institute: Monoclonal antibodies. What monoclonal antibodies are, rituximab binding CD20, flu-like symptoms, allergic reactions and cytokine release syndrome.
The next step on this is the same as on everything else here: answer questions and read the rationales. Our pharmacology practice questions are the closest set to what this page covers.
One question from the pharmacology set
A client with heart failure is started on furosemide 40 mg PO daily. Which findings should the nurse report to the provider before administering the next dose? Select all that apply.
Rationale
Furosemide is a loop diuretic, so the two things you are watching are potassium and kidney function. A potassium of 2.9 mEq/L is below the 3.5–5.0 reference range and puts the client at risk for dysrhythmia — hold and report. Muscle cramps with palpitations are the clinical face of that same hypokalemia, so they are reported together, not separately. A creatinine that doubles signals the diuresis has outrun renal perfusion. A blood pressure of 132/78 and a 1 kg loss are the expected response to the drug working, not reasons to hold it.
Answer: A, D, E
Common questions
Why is the first monoclonal antibody infusion the highest-risk dose?
For drugs such as rituximab, most severe and fatal infusion reactions occurred with the first infusion, so it is started slowly with premedication, close observation and emergency equipment ready. Later reactions remain possible.
Can a nurse speed up a -mab infusion that is running late?
Rate increases follow the ordered titration schedule and depend on stable vital signs. Running the infusion faster to save time raises the risk of an infusion reaction and is outside the order.
What should a patient report after a -mab infusion?
Fever, chills, cough, breathing difficulty, rash, swelling or other signs of infection, because reactions can be delayed and these drugs can weaken immune defence. Throat tightness or collapse needs emergency care.
More on pharmacology
Guides on this