The phenomenon of de-influencing gained traction in early 2023, particularly within the beauty sector, where influencers began publicly criticizing cosmetic brands while simultaneously promoting alternative, often more affordable, products or “dupes”. Our online experiment with 589 participants investigates the effect of de-influencing with an alternative product recommendation on source credibility and purchase intent compared to influencing, with brand image acting as a mediator. The findings demonstrate significant variations in the assessment of the influencer’s trustworthiness and expertise between the two groups. Moreover, de-influencing positively affects brand image, which partially mediates the relationship between source credibility and purchase intention. However, no significant differences in purchase intention were observed when a brand was endorsed by an influencer, compared with when it was presented as an alternative in a de-influencing context. Our findings advance the emerging body of literature on de-influencing by empirically distinguishing its effects from those of conventional influencer marketing. From a managerial perspective, de-influencing is perceived as more credible, positively impacting the brand image of the recommended alternative, underscoring its potential as a strategic marketing approach.