<p>Mounjaro (tirzepatide) is a recently approved medication for type 2 diabetes that is increasingly used off-label for weight loss, in part due to extensive promotion on social media. X has emerged as a major venue for discussions about weight-loss medications, yet limited research has examined public discourse surrounding Mounjaro. Identifying key influencers and mapping conversation dynamics are critical for understanding how social media may shape public awareness and adoption of emerging pharmacotherapies. This study examined Mounjaro-related discourse on X to identify influential information sources, dominant discussion topics, and public sentiment. A quantitative, exploratory observational design was employed using social network analysis and automated sentiment analysis of publicly available tweets. The dataset included 5,566 tweets generated by 5,641 unique users collected between January 9 and February 24, 2025. Using NodeXL, betweenness and in-degree centrality measures were used to identify influential users and content sources, and cluster analysis identified dominant discussion topics within the network. Sentiment analysis assessed the overall tone of Mounjaro-related tweets. Results indicated that the most influential users were predominantly non-medical individuals, including public figures and patients sharing personal experiences. Overall sentiment toward Mounjaro was largely positive, with 62.6% of tweets expressing favorable attitudes. Network clusters centered on weight loss, comparisons with Ozempic and Wegovy, pharmaceutical branding, and diabetes treatment. These findings highlight the prominent role of non-expert voices in shaping online discourse and underscore the need for evidence-based health communication strategies on social media.</p>