Influencers are the main source of disseminated health-related content, and this content is also more accepted by the population compared to content disseminated by health institutions. The objective of this study is to determine the communication strategies and content that generate more engagement with users who follow health and pharmacy topics. We analysed six Instagram accounts of Spanish influencers related to science and health communication with more than 30,000 followers. We evaluated user interaction metrics, the type of content shared, and calculated the degree of engagement based on the number of followers and interaction with the content. The accounts with the highest degree of engagement, such as @Farmacia_enfurecida with 166,000 followers, an engagement of 3.7% of likes per publication and 0.91% in comments, are accounts with a smaller number of followers. Communication techniques such as health product sweepstakes are the most effective in achieving user interaction. Engagement is a determining variable in the impact of health-related content dissemination and is not necessarily linked to a greater number of followers; the profiles that use a greater number of reels and infographics are those with a higher engagement value.