Have you heard of patients having immune reactions to solid lip implants?

I had lip implants place over almost 1 month ago. At 3 weeks, my lips began to swell, and the implants became harder. I went to my plastic surgeon, who prescribed more antibiotics, however because of the variable nature of the swelling, and the lack of pain at any particular site, and because onset was so late (and at 21 days, suggesting an immune response) I believe this is a form of rejection. I began taking antihistamines like Benadryl and Clartin and have seen a marked improvement in my lips.