Have you asked your doctor about the Zostavax injection? In looking at information provided by the FDA regarding Zostavax, it looks like there are some folks who should NOT get the vaccine. Here is an excerpt:
Who should not be immunized with Zostavax?
People who are allergic to neomycin, or any component of the vaccine should not receive Zostavax. Zostavax is a live vaccine and should not be given to individuals who have a weakened immune system caused by treatments that they are taking such as radiation, a class of drugs called corticosteroids, or due to conditions such as AIDS, cancer of the lymph, bone or blood.
You would need to ask your own doctor if any medications you might be taking would prevent you from getting the vaccine.