Infusion Reactions: These side effects may occur during or within 24 hours of any Gazyva infusion. Some infusion reactions can be serious, including, but not limited to, severe allergic reactions (anaphylaxis), acute life-threatening breathing problems, or other life-threatening infusion reactions. If a patient has a reaction, the infusion is either slowed or stopped until the patient’s symptoms are resolved. Most patients are able to complete infusions and receive medication again. However, if the infusion reaction is serious, the infusion of Gazyva will be permanently stopped. The patient’s healthcare team will take a few steps to help lessen any side effects the patient may have to the infusion process. The patient may be given medicines to take before each Gazyva treatment. Signs of infusion reactions may include: dizziness, nausea, chills, fever, vomiting, diarrhea, breathing problems, chest pain