What Is RSO Oil? (Rick Simpson Oil Explained)
Medically reviewed · Updated January 2026
Rick Simpson Oil (RSO) is a highly concentrated cannabis extract containing very high levels of THC.
RSO is not an approved medical treatment. In the UK, cannabis-based products containing THC are only available via prescription from a GMC-registered specialist.
Unlike CBD oil, RSO’s high THC content places it under strict legal control. See our buy RSO online guide for legal context.
Is RSO Legal in the UK?
RSO is legal only when prescribed by a specialist doctor. Home production, possession without prescription, or unlicensed sales are illegal under UK law.
Medical Disclaimer
This content is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.