Individuals who have had chemotherapy or blood transfusions: allergies?

I was diagnosed in 1997 with non-Hodgkin's lymphoma and have had to endure chemo twice and yes I have suffered some of these same problems besides the chemo causing my hair to fall out it also caused the loss of my teeth. I also have developed allergic reactions to several medications that never used to bother me such as codeine and its derivatives such as oxycodone and hydrocodone and several other pain killers which is bad because I am unfortunately in constant severe pain. I also am in remission at this time but unfortunately there is no cure unless I can find a bone marrow donor match and then there is no guarantee. I hope you continue to be cancer free and live a long and prosperous life. Oh, Happy New Year