I Have Had Rituxin Treatments And Have Had Allergic Reactions

I have had rituxin treatments and have had allergic reactions in the past. My Dr. is going to give me a new administration of it--a shot instead of the infusion. I am very fearful of another reaction, especially since it always has to be slowed down when infusing due to the reactions. Do you think I should get the shot of rituxin? Reason given for the shot instead of the infusion is that I had to be admitted to hospital for infusion because it had to be administered very slowly