Yes. Adults can also be vaccinated, and it is especially recommended if you are at risk of infection as described here. Vaccination will decrease your chance of being infected in the future and of getting acute hepatitis B. However, you might have already been infected without knowing it, in which case getting vaccinated will not have any benefit for you. Because of this, your health-care provider may give you a blood test before vaccinating you, to find out whether you have already been infected.