Hepatitis B vaccine and antipyrine clearance.

: The impact of hepatitis B vaccine on hepatic mixed function oxidase activity was studied using antipyrine as a probe. Fifteen health care workers who elected to take the vaccine due to occupational risk were the subjects. Each subject received all three vaccinations over a period of six months. Antipyrine (500 mg) was administered orally prior to the first vaccination, 1 week subsequent to each vaccination, and one month after the final vaccination, and antipyrine clearance, CL/F was estimated from concentrations of antipyrine in saliva collected 24 hr after each antipyrine dose. The mean (+/- SD) pre-vaccination CL/F was 3.65 (+/- 0.75) 1/hr. Post vaccination mean CL/F values deviated by no more than 8.8% and none of the post vaccination values were significantly different from the pre-vaccination mean. It is inappropriate to extrapolate findings concerning one antiviral vaccine and its putative effect on drug metabolism to other antiviral vaccines.