RSO Oil vs CBD Oil: A Comprehensive Comparison
Explore the key differences between RSO oil and CBD oil in our comparison review, from effectiveness to sourcing.
The short answer
No health agency has approved RSO to treat cancer. The U.S. Food and Drug Administration has not approved cannabis flower, cannabis oil, or RSO for any cancer use. RSO is a high-THC extract. Lab tests show THC and CBD can kill cancer cells in dishes and slow tumor growth in mice. Human trial data on RSO as a cancer treatment does not exist. Tell your oncology team before you use any cannabis product.
What RSO is
RSO stands for Rick Simpson Oil. Rick Simpson, a Canadian, publicized the extract in 2003. He said it cleared his skin cancer. That account is one case report. A case report is not a trial and does not show cause.
Makers soak dried cannabis flower in a solvent, then evaporate the solvent. What remains is a thick, dark oil. Solvents in use include ethanol, isopropyl alcohol, naphtha, and butane. THC content in tested samples runs from 60% to 90%. One gram of 70% THC oil holds about 700 mg of THC.
What is RSO Oil Used For: A Comprehensive Guide
Lab evidence compared with human evidence
Preclinical work uses isolated THC or CBD at controlled doses on cancer cell lines. Those studies do not measure survival. Doses in a dish do not scale to a human body. Reviews of human trials found no survival benefit from cannabinoids for cancer. The National Cancer Institute states that no cannabis product has FDA approval for cancer treatment.
What human trials show
- The FDA approved two synthetic THC drugs for chemotherapy-induced nausea and vomiting: dronabinol (Marinol) and nabilone (Cesamet). Approval came in 1985.
- Nabiximols (Sativex), a spray with THC and CBD, is approved in some countries for cancer pain and spasticity. It is not approved in the U.S.
- Epidiolex, a CBD drug, is approved for certain seizure disorders, not for cancer.
- Cochrane reviews of cannabinoids for cancer pain report pain relief that is modest, with evidence graded low to moderate quality.
- No phase 3 trial has tested RSO with survival or tumor response as the endpoint.
Dosing and labels
There is no standard RSO dose. THC per drop changes with concentration, and batches vary. Published clinic protocols often start near 0.1 mL once or twice per day and raise the amount over weeks. For scale, FDA labeling for dronabinol starts at 2.5 mg to 10 mg per dose. One drop of 70% THC oil can carry far more than that. Start low and go slow is the common harm-reduction rule, but no dosing schedule has been validated for cancer.
Risks and drug interactions
- Intoxication, impaired coordination, and impaired driving
- Fast heart rate, low blood pressure, dizziness
- Anxiety, panic, and paranoia, more common in people new to THC
- Cannabinoid hyperemesis syndrome with heavy, long-term use
- Falls and confusion in older adults
- Interactions: THC and CBD affect CYP2C9, CYP3A4, and CYP2D6 enzymes. This can change blood levels of warfarin, clopidogrel, tacrolimus, and some chemotherapy drugs
- Contaminants: homemade oil can hold solvent residue, pesticides, and mold
- Inhaled cannabis carries a risk of fungal infection in people with weakened immune systems
Legal status in the U.S.
Cannabis is Schedule I under the federal Controlled Substances Act. More than 20 states allow adult use, and more than 30 run medical programs. Those counts change each year. RSO sold in state-licensed dispensaries goes through testing for potency and contaminants. Buying oil online from an unlicensed seller breaks federal law, and the product content is unverified.
Questions for your oncology team
- Does any cannabis product interact with my current drugs?
- Will THC affect my blood counts, liver enzymes, or sedation level?
- Are there trials I can join?
- If I try RSO, what dose and product source do you suggest, and what side effects should trigger a call?
Bottom line
RSO is a concentrated THC extract with no approved cancer indication. Evidence for cancer treatment rests on lab work, not human survival data. Approved cannabinoid drugs exist for nausea and vomiting from chemotherapy. Pain evidence is weak to moderate. Risks include intoxication, falls, heart rate changes, and drug interactions. Tested products from licensed sellers reduce contaminant risk.