Ocrevus (ocrelizumab) is a medication used to treat multiple sclerosis (MS), administered by infusion either intravenously or subcutaneously. One of the important considerations during and after Ocrevus infusion is the possibility of **infusion reactions**, which can range from mild to severe and require careful monitoring.
**What are infusion reactions with Ocrevus?**
Infusion reactions are adverse responses that occur during the administration of Ocrevus or within 24 hours afterward. These reactions happen because the immune system reacts to the medication being infused. Symptoms can vary widely but often include:
– **Skin-related symptoms:** Itchy skin, rash, hives, redness, swelling, or flushing.
– **Respiratory symptoms:** Shortness of breath, throat irritation, throat swelling (edema), bronchospasm (tightening of the airways).
– **Cardiovascular symptoms:** Low blood pressure, a fast or irregular heartbeat.
– **General symptoms:** Fever, fatigue, headache, dizziness, nausea.
– **Severe allergic reactions:** Anaphylaxis, which is a life-threatening emergency involving difficulty breathing, swelling, and a drop in blood pressure.
These symptoms can appear during the infusion or up to 24 hours afterward, so patients are closely observed during and after treatment.
**Why do infusion reactions happen with Ocrevus?**
Ocrevus is a monoclonal antibody that targets specific immune cells involved in MS. Because it is a biologic agent, the body may recognize it as foreign and mount an immune response. This immune activation can cause the symptoms described above. The first infusion, or the initial loading dose, tends to carry a higher risk of infusion reactions compared to subsequent doses.
**How are infusion reactions managed and prevented?**
To reduce the risk and severity of infusion reactions, healthcare providers take several precautions:
– **Pre-medication:** Before each Ocrevus infusion, patients are typically given corticosteroids (like methylprednisolone or dexamethasone) and antihistamines (such as diphenhydramine or desloratadine). These medications help suppress the immune response and reduce allergic symptoms.
– **Slow infusion rate:** The infusion is started slowly and can be adjusted based on the patient’s tolerance.
– **Close monitoring:** Patients are monitored during the infusion and for at least an hour afterward, especially during the first infusion. Any signs of reaction are addressed immediately.
– **Post-infusion observation:** Since reactions can occur up to 24 hours later, patients are advised to report any delayed symptoms such as rash, swelling, or breathing difficulties promptly.
**What should patients do if they experience infusion reactions?**
If symptoms like rash, itching, swelling, difficulty breathing, or throat tightness occur during or after the infusion, patients should notify their healthcare provider immediately. Mild reactions may be treated with additional medications and slowing or stopping the infusion temporarily. Severe reactions require emergency treatment.
**Are there differences in infusion reactions between intravenous and subcutaneous Ocrevus?**
Ocrevus was initially given intravenously every six months, with infusions lasting several hours. More recently, a subcutaneous form (injected under the skin) has been approved, which takes about 10 minutes to administer. Both forms can cause infusion reactions, but the subcutaneous form may have a different profile of local reactions at the injection site, such as pain, swelling, discoloration, or itching. Systemic infusion reactions like rash, headache, or nausea can still occur with subcutaneous administration.
**Additional considerations**
– Infusion reactions are among the most common side effects of Ocrevus, along with infections such as upper respiratory tract infections.
– Because Ocrevus affects the immune system, patients are also monitored for infections and other immune-related side effects.
– The risk of infusion reactions decrease
