Compositions and methods effective for eliciting an immune response for preventing or reducing infection or improving clinical outcomes caused by Bacillus anthracis are provided. The compositions include a naturally occurring or synthetic protein, peptide, or protein fragment containing all or an active portion of an antigenic epitope associated with anthrax toxin proteins optionally combined with a pharmaceutically acceptable carrier. The preferred antigenic epitopes correspond to immunogenic regions of protective antigen, lethal factor or edema factor, either individually or in combination. In addition, methods and compositions containing antibodies for reducing the effects of anthrax toxins are described. The methods involve administering to a human or animal the compositions described herein in a dosage sufficient to elicit an immune response or treat the anthrax infection.