I am an oncology RN and I am very familiar with administering Rituxan for lymphomas and the like. We adninister steroids and tylenol to prevent "allergic responses" to medication (fevers, chills, rashes drop in blood pressure) We monitor blood pressure qauite frequently every 1/2 hour or hour before adjusting rate of medication. We slow the infusion if any allergic responses develop. Therefore it can take 3-12 hours to infuse depending on how the patient tolerates. You should not take any blood pressure medication before receiving Rituxan. I dont know how it affects MG patients though and have never received it myself.