RSO (Rick Simpson Oil)

Definition

RSO stands for Rick Simpson Oil, named after Rick Simpson, a Canadian cannabis activist who promoted a specific full-spectrum extract starting in the mid-2000s. RSO is a crude, whole-plant cannabis concentrate that retains cannabinoids, terpenes, chlorophyll, waxes, and plant lipids — making it dark and bitter Weak / limited. Most modern commercial RSO is produced with food-grade ethanol; historically, naphtha was used Weak / limited^[1]. The extract is unrefined: it undergoes no winterization, distillation, or chromatographic purification, which distinguishes it from other cannabis concentrates like distillate.

Chemistry and potency

RSO made from high-THC cultivars typically contains 40–80% total cannabinoids by weight, though batch-to-batch potency varies significantly with the source material, extraction efficiency, and solvent retention Weak / limited^[2]. Most commercial RSO is THC-dominant; CBD-rich versions exist but are less common. A typical grain-of-rice-sized dose (approximately 0.1 g) from high-potency batches can deliver 40–80 mg of THC—substantially above the 5–10 mg threshold recommended for non-tolerant oral cannabis users Weak / limited^[2]. Because RSO is a crude extract, cannabinoid and terpene profiles are highly dependent on starting material and production conditions; lab testing is essential for determining actual potency and contaminants.

Effects and pharmacology

As an oral THC preparation, RSO produces slow onset (30–120 minutes), prolonged duration (4–8+ hours), and strong psychoactivity, primarily because ingested THC is converted to 11-hydroxy-THC in the liver, a more potent metabolite Strong evidence^[3]. In legal and gray markets, RSO is used as a high-dose THC vehicle for patients managing chemotherapy side effects, chronic pain, insomnia, and appetite loss, though controlled clinical evidence for these specific uses is limited Weak / limited.

Claim: RSO cures cancer

RSO has not been shown to cure cancer in controlled human trials. Rick Simpson's widely circulated claims that RSO can cure cancer are not supported by clinical evidence. Preclinical research (cell and animal studies) shows that cannabinoids can affect tumor biology in laboratory conditions, but this has not translated to demonstrated human cures Disputed^[4][5]. The U.S. National Cancer Institute and FDA explicitly state that no form of cannabis is approved as a cancer treatment Strong evidence. Anyone considering cannabis for cancer should consult an oncologist; cannabis should not replace conventional cancer therapy.

Safety and sourcing

Lab-tested RSO from licensed producers is superior to black-market or home-made versions because it has been tested for residual solvents, microbial contaminants, and potency No data. Commercial production uses closed-loop equipment and professional purging to minimize solvent residue. Uncontrolled home preparation carries fire, explosion, and contamination hazards. RSO is not inherently 'more medicinal' than other cannabis concentrates simply because it is full-spectrum—that is marketing language, not pharmacology. The crude composition makes standardization difficult, so dose variability is a real concern with untested batches.

Sources

How this page was made

Related

• Distillate — A refined cannabis concentrate made by isolating and recondensing cannabinoids under heat...
• Neem Oil Application — Cold-pressed neem oil for vegetative pest control: what works, what doesn't, and how to ap...
• Tolerance Break (T-Break) — A period of cannabis abstinence to restore THC sensitivity through CB1 receptor recovery.