Background: Reports of hospitalization associated with Diamond Shruumz products in October 2024, a mushroom-containing product, led to a manufacturer’s recall that restricted the sale, distribution, and accessibility of this new and emerging psychoactive product. This study sought to assess the continuing online availability in a diverse e-commerce landscape. Objective: Identify and characterize online availability of mushroom-containing edible product pre and post recall initiation. Methods: Retrospective online market surveillance of Diamond Shruumz products using structured and automated search queries were employed to identify online product marketing and availability. Online surveillance included monitoring of multiple social media platforms, cannabis e-commerce websites, and search engine queries between June 22 – June 27, 2024, immediately preceding the manufacturer-initiated recall. Post-recall simulated purchases were then conducted on July 12, 2024 on platforms, websites and domains identified as continuing to actively market and sell through online product listings. Results: Prior to product recall, a total of 4,117 product listings across 1,600 (38.86%) social media posts and user-generated comments, 11 (0.27%) shops across cannabis e-commerce websites, and 2,509 (60.94%) hyperlinks from Internet search queries were generated for further content analysis. Review of online sources revealed 49 social media posts, 8 e-commerce shops and 67 domains that were identified as actively marketing and selling products pre-recall. Post-recall, we identified 45 (67.16%) remaining domains that continued to market the product from these different online sources. Simulated purchases revealed that 15 (33.33%) domains successfully transacted test purchases and 30 (66.66%) transactions failed because of account verification or payment failure. Conclusions: The Diamond Shruumz recall personifies ongoing challenge of unknown consumer harm associated with new and emerging substances marketed and sold on the Internet, especially concerning as these products appeal to younger audiences with a variety of edible flavored products. While a recall was initiated and products became unavailable, our study found that post-recall online vendors continued to market and sell product. This indicates that there are ongoing challenges to effectuate recalls and online enforcement in a diverse e-commerce landscape that can rapidly bring new and novel psychoactive substances to market.