Hi Kathy

Thanks for your question.

I have tried to answer this myself. In my discussions with the manufacturer they will not confirm that they are the same vaccine or if the formulation is slightly altered. They did, however, quote the results of some research trials which varied insignificantly between the two products.

Based on the results of this inquiry, I cannot tell you the difference between these vaccines on record. Here’s what I can say. A rabies vaccine is required by law and is documented in the medical record and may be assessed in cases where there are incidences of bites or import/export to other countries. Indicating the length of activity of the product becomes part of this record. Having said that, if you received a 1-year rabies vaccine and want to claim that it is up to date 2 years later, you won’t have the documentation to support it simply by saying a 3-year rabies product is the same as a 1-year. You have to have the product information accompany the record. Despite medical arguments, this is a regulatory point that can’t be argued. So my simple recommendation is to always get the 3-year vaccine in order to reduce the frequency of administration of the vaccine and give the longest duration of documentation for protection against rabies.

I hope this answer is helpful.

Dr Clayton Greenway