We investigated whether the location and format of risk information on branded prescription drug websites influence consumers' knowledge and perceptions of the drug's risks. Participants (Internet panelists with high cholesterol [n = 2,609] or seasonal allergies [n = 2,637]) were randomly assigned to view a website promoting a fictitious prescription drug for their condition. The website presented risk information at the bottom of the homepage, or at the bottom of the homepage with a signal above indicating that the risk information was located below, or on a linked secondary page. We also varied the format of risk information (paragraph, checklist, bulleted list, highlighted box). Participants then answered questions on risk recall and perceptions. Participants recalled fewer drug risks when the risks were placed on a secondary page. The signal had little effect, and risk information format did not affect outcomes. The location of risk information on prescription drug websites can affect consumer knowledge of drug risks; however, signals and special formatting may not be necessary for websites to adequately inform consumers about drug risks. We recommend that prescription drug websites maintain risk information on their homepages to achieve "fair balance" as required by the U.S. Food and Drug Administration.