A radioconjugate consisting of 6-fluorodopamine labeled with fluorine F18 (6-[18F]FDA), with potential diagnostic activity. Upon administration, 6-[18F]FDA is taken up by presynaptic sympathetic nerve endings via the norepinephrine transporter (NET) uptake-1. Once inside, 6-[18F]FDA is rapidly converted by dopamine-beta-hydroxylase into 6-[18F]fluoronorepinephrine (6-[18F]FNE) and stored into neuronal storage vesicles. Upon positron emission tomographic (PET) scanning of the F18, sympathetic innervated regions can be visualized, such as those in pheochromocytoma.