This study is an unblinded, voluntary, open-label toxicity trial assessing zidovudine as a candidate agent for post-exposure chemoprophylaxis for healthcare workers (HCW) sustaining occupational exposures to HIV. The two secondary purposes of this study are: 1) to assess the effect of zidovudine chemoprophylaxis on the temporal sequent of the appearance of markers of HIV infection should it occur in a HCW(s) taking zidovudine chemoprophylaxis; and 2) to describe the epidemiology of exposures to HIV for which zidovudine chemoprophylaxis is elected in institutions participating in this study. Zidovudine is initiated as soon as possible for exposed HCW, but no longer than 72 hours post-exposure, at a dose of 200 mg 6x per day for 3 days- followed by 290 mg 5x per day for 25 days; total treatment course is 28 days. Exposed HCW are followed for a minimum of 12 months. After the baseline enrollment visit, follow-up visits occur at 2 weeks, 4 weeks, 6 weeks, 3 months, 6 months and 12 months. Individuals are assessed for drug toxicity as well as for early signs of HIV infection. Individual HCW who have elected to take zidovudine have, in general, tolerated the drug well. Subjective toxicities occur in the majority of HCW; nonetheless, symptomatology has not correlated at all with objective hematologic toxicities. No investigator has discontinued any course of zidovudine because of laboratory toxicity in a HCW. One HCW has developed evidence of HIV infection following exposure despite administration of zidovudine.
