Can i be allergic to the rabies vaccine?

Sure: You literally can be allergic to anything, including any vaccine. A vaccine, like any medicine, is capable of causing serious problems, such as severe allergic reactions. The risk of a vaccine causing serious harm, or death, is extremely small. Serious problems from Rabies Vaccine are very rare. Several brands of Rabies Vaccine are available in the United States, and reactions may vary.

Yes: It is very difficult to call it a true allergy since very serious reactions can happen simply as a side effect of the Rabies Vaccine itself, but it is definitely possible to have an allergic reaction to the vaccine.