Finding feasible strategies to distribute antibiotics quickly to the general public in response to an anthrax attack remains a difficult challenge. Among the proposed strategies is the pre-event placement of pharmaceuticals in individual households for use only as directed by public health authorities. These medications (known as “MedKits”) would allow many exposed persons to begin treatment quickly while reducing the number who visit on points of dispensing, the primary distribution strategy. This paper describes a model that estimates the expected number of deaths in an anthrax attack by modeling the logistics of the response and the use of MedKits. The results show that increasing the number of MedKits distributed can reduce the expected number of deaths. When the population has more potential exposures, deploying MedKits is more effective. The MedKits reduce the number of potential exposures who seek prophylaxis, which allows those truly exposed (but without MedKits) to receive medication sooner, which saves lives. Beyond the scenarios considered here, the ability to predict this benefit in other scenarios will be valuable to public health officials who are considering this option.