Recent research explores the high proliferation of conspiracy theories about COVID-19 vaccination, and their potential effects within digital media environments. By means of a 2 × 2 experimental design (N = 945) conducted in Romania, we explore whether exposure to media messages promoting conspiracy theories about vaccination versus media messages debunking such conspiracy narratives could influence people’s intention to either support or argue against vaccination in front of their friends and family (interpersonal influence). We also analyze the moderation effects of (...) education and critical thinking. Main results show that both conspiracy and counter-conspiracy media content about vaccination negatively affect people’s willingness to discuss the topic with others, which offers support for a silencing effect. Education and critical thinking moderate the main effects, but only to some extent and in certain experimental conditions. (shrink)