HIB Vaccine

Has anyone ever tried to give a HIB vaccine to an adult (per their request) and if so, what code did you use? My insurance is denying stating invalid code / modifier (which I did not have a modifier on it), which makes me think they might pay with a different code and/or modifier - I used the pedi code 90645.
Thanks
Sara

Dec 22nd, 2009 -

90648

worked for me in an adult- pre-splenectomy. No modifier but did charge for admin, of course