The Effects of Message Type and Sponsorship Disclosure in Influencer Marketing of Prescription Drugs

Abstract This study examined the effects of message type and sponsorship disclosure of prescription drug influencer marketing on consumers’ attitude toward the ad and behavioral intentions. The Persuasion Knowledge Model was used as a theoretical framework to understand the underlying mechanism of the effects. An online experiment with 2 (message type: unbranded vs. branded) × 2 (disclosure: absence vs. presence) between-subject factorial design was conducted. Unbranded message and message without disclosure resulted in lower persuasion knowledge activation, leading to higher attitude toward the ad and behavioral intentions. A significant interaction effect was also found. Theoretical, practical, and ethical implications are discussed. Supplemental data for this article is available online at https://doi.org/10.1080/08911762.2021.1913273 .