Introduction: Cannabis products containing delta-8-THC became widely available in most of the United States in late 2020 and rapidly became a significant source of revenue for hemp processing companies, especially in states where use of delta-9-THC remains illegal or requires professional authorization for medical use. Scientific research on the use of delta-8-THC is scarce, previous clinical studies included a combined total of 14 participants, leading some state governments to prohibit it until its properties and effects are better understood. Methods: Researchers developed an online survey for delta-8-THC consumers addressing a broad range of issues regarding delta-8-THC, including use for the treatment of health and medical conditions. Previous survey studies on the medical use of cannabis and cannabis products informed survey components. Results: Patterns of delta-8-THC use had both similarities with and differences from the use of delta-9-THC cannabis and products. Administration methods were primarily edibles (64%) and vaping concentrates (48%). About half of the participants (51%) used delta-8-THC to treat a range of health and medical conditions, primarily anxiety or panic attacks (69%), stress (52%), depression or bipolar disorder (46%), and chronic pain (41%). Participants compared delta-8-THC very favorably with both delta-9-THC and pharmaceutical drugs and reported substantial levels of substitution for both. Most participants did not inform their primary care provider of their delta-8-THC use (78%) and were not confident of their primary care provider's ability to integrate medical cannabis into their treatment (70%). Knowledge of effective dosages was low, and participants' knowledge of delta-8-THC was primarily from the Internet and their own experiences. Conclusion: Harm reduction is a central component of public health. Although the legal environment is becoming more restrictive for delta-8-THC in comparison to delta-9-THC, results suggest that delta-8-THC may be equally effective for desired purposes of cannabis use and lower in undesirable or adverse effects. All policies and practices should be informed by empirical evidence. Considerable research will be needed to systematically verify the patterns reported by participants, and collaborations among academic researchers, government, and the cannabis industry may be valuable in developing the knowledge base for delta-8-THC and other cannabinoids.