Codeine is one of the most common opioid medicines for treating pain. Australia introduced policy changes in February 2018 to up-schedule codeine to prescription-only medicine due to concerns of adverse effects, opioid dependency and overdose-related mortality. This study investigated the frequency and content of messages promoted on Twitter by four Australian peak pain organizations, pre- and post-policy implementation. A time series analysis examined frequency of Twitter posts over a 48-week period. Text analysis via Leximancer examined message content. Results showed that promotion and education of the pending policy change dominated the Twitter feed prior to up-scheduling. However, immediately following policy change, there was a shift in content towards promoting conferences and research, and a significant decrease in the frequency of codeine-related posts, compared to opioid-related non-codeine posts. The findings suggest that pain organizations can provide timely and educational policy dissemination in the online environment. They have implications for individuals with chronic pain who use the Internet for health information and the degree to which they can trust these sources, as well as health professionals. Further research is required to determine if public health campaigns can be targeted to prevent opioid-related harm and improve pain care via this increasingly used medium. Perspective: This study presents a first look at what information is being communicated by influential pain organizations who have an online Twitter presence and how messages were delivered during a major policy change restricting access to codeine medicines. Insights could drive targeted future online health campaigns for improved pain management.