Numerous inhibitors of EDHF have been defined in animal tissues. Of these, miconazole has proven to be safe when administered to humans as a topical and parenteral antifungal agent. At levels that are attained with routine clinical use, it has a rapid onset of action with high specificity of inhibition of EDHF in animal models. This study is designed to investigate the safety and efficacy of intra-arterial miconazole in inhibiting BK-mediated forearm vasodilation in normal volunteers.