Rick Simpson Oil, usually shortened to RSO, is a thick full-spectrum cannabis extract with a very high cannabinoid concentration. Its reputation includes medical claims that are not supported by clinical evidence, so it is important to separate what the product is from what people say it can treat. Anyone considering it for a health condition should speak with a qualified healthcare professional.
What Is Rick Simpson Oil (RSO)?
RSO is a highly concentrated, full-spectrum cannabis extract made from the whole plant. Canadian engineer Rick Simpson developed the oil in the early 2000s, and it now carries his name. Unlike isolated cannabinoid products, RSO keeps the plant’s full chemical profile intact. Producers extract cannabinoids like THC and CBD alongside terpenes, then remove the leftover plant matter. The finished oil looks dark, thick, and tar-like, and it delivers far stronger effects than typical cannabis flower.
According to WebMD, Simpson found that marijuana eased dizziness and other symptoms he developed after a workplace fall. He later applied cannabis oil to basal cell skin cancers on his arm, and reported that the cancers disappeared within days. Simpson then published his extraction method online rather than selling the oil commercially, so, as WebMD notes, no single official “Rick Simpson Oil” product exists. Many licensed manufacturers now sell their own versions under the RSO name.
How Is RSO Made?
Producers make this concentrate by soaking ground cannabis flower in a solvent, then straining, evaporating, and purifying the extract. Here is the process step by step.
Step 1: Grind the flower. Producers grind dried cannabis thoroughly before extraction. Finer grinding increases surface area, which improves solvent contact and extraction efficiency.
Step 2: Soak the flower in solvent. Producers submerge the ground flower in a solvent to pull out the cannabinoids. Grain alcohol remains the most common choice, though some makers use ethanol or butane instead. Simpson’s original method used naphtha, but most modern producers favor food-grade ethanol for safety.
Step 3: Strain and filter. Producers drain the solvent away from the plant matter, then filter it repeatedly. Root Sciences explains that multiple filtration cycles remove all remaining plant debris from the solvent-dissolved compounds.
Step 4: Evaporate the solvent. Producers heat the mixture slowly to evaporate the alcohol. Arbors Wellness describes how producers often use a low-heat vessel, such as a rice cooker, to boil off the remaining solvent safely. This step requires careful temperature control, since overheating destroys valuable cannabinoids and terpenes.
Step 5: Purify and lab-test the oil. Commercial producers repeat purification cycles to strip out any leftover solvent traces. Root Sciences adds that comprehensive lab testing then confirms the oil’s potency, purity, and safety before it reaches dispensary shelves. Modern facilities use closed-loop extraction systems, which improve safety and consistency far beyond Simpson’s original home-based method.
The finished oil typically tests very high in THC. RSO commonly ranges between 60% and 90% THC, alongside a broad supporting cannabinoid and terpene profile.
How Does It Differ From Other Cannabis Concentrates?
RSO differs from other concentrates mainly in its full-spectrum composition and its intended use for oral or topical consumption rather than inhalation.
RSO vs. THC Distillate: What’s the Difference?
The key difference is that RSO retains the whole plant’s compounds, while distillate isolates a single cannabinoid. Leafwell explains that distillate contains 90% or more of one target cannabinoid, with virtually no terpenes or flavonoids left behind. This refining process creates a clear, flavorless, odorless oil.
It also keeps everything distillate strips away. The concentrate’s rich blend of cannabinoids, terpenes, and flavonoids makes it one of the most sought-after full-spectrum medical extracts on the market. Many users report that this broader compound profile creates stronger, more balanced effects than isolated THC alone.
RSO vs. Live Resin: What’s the Difference?
The two differ mainly in starting material and intended consumption method. Live resin comes from fresh-frozen cannabis and is designed for inhalation, while RSO comes from cured flower processed with ethanol and is designed for oral or topical use. Both preserve a full cannabinoid and terpene profile, but live resin favors flavor and aroma, while RSO favors potency and medicinal application.
RSO vs. FECO: What’s the Difference?
RSO and FECO (Full Extract Cannabis Oil) both preserve the whole plant, but they differ in solvent choice.FECO typically uses food-grade ethanol, while traditional RSO relies on isopropyl alcohol or naphtha. These stronger solvents pull heavier concentrations of THC, along with chlorophyll and plant waxes, giving RSO its characteristically darker color and harsher taste.
What Is RSO Used For?
People use it orally, sublingually, or topically, depending on their goals.
- Oral ingestion: Most users swallow small amounts directly or mix RSO into food for long-lasting, digestion-based effects.
- Sublingual use: Placing RSO under the tongue speeds absorption into the bloodstream.
- Topical application: Users apply RSO directly to the skin for localized relief. Simpson used this method first, on his own skin cancer.
- Capsules: Some manufacturers pre-load RSO into capsules for precise, discreet dosing.
Regardless of method, it delivers powerful, long-lasting effects. Its full-spectrum profile also creates what researchers call the entourage effect. This synergy between cannabinoids and terpenes may explain why full-spectrum products often feel stronger than isolated THC.
Does RSO Have Medical Benefits?
It may offer supportive benefits for pain, nausea, and appetite, but no clinical evidence confirms it treats cancer.
RSO’s reputation grew largely from anecdotal cancer stories. However, the evidence tells a more careful story. WebMD reports that research has not shown RSO or other cannabis oils can treat cancer, though early studies on THC show some encouraging preliminary results in labs.
The National Cancer Institute maintains an evidence-based summary reviewing cannabis and cannabinoids in cancer care. Its patient-facing summary, hosted by Siteman Cancer Center, states plainly that no ongoing human studies of cannabis as a cancer treatment currently appear in the CAM PubMed database, and that existing small studies point to a need for larger trials.
That said, cannabis compounds show real promise for supportive care. WebMD notes that cannabis oils containing THC may help control chemotherapy-related nausea and vomiting, and evidence also supports their use for pain relief and appetite improvement. People also explore RSO for:
- Chronic pain and inflammation
- Sleep disturbances
- Anxiety and stress
- Muscle spasms
- Appetite loss
Treat these as potential, not proven, benefits. Talk with a doctor before using RSO for any medical condition, especially a serious one like cancer.
What Are Its Benefits?
RSO offers several practical advantages over other cannabis products:
- Full-spectrum composition: RSO preserves the plant’s natural cannabinoid and terpene balance, which may enhance therapeutic effects through the entourage effect.
- High potency in small amounts: RSO delivers strong, long-lasting effects from tiny doses, so a little oil goes a long way.
- Flexible administration: Users can take RSO orally, sublingually, or topically, based on personal preference and condition.
- Wide availability: Leafwell reports that several cannabis manufacturers now produce lab-tested RSO for sale throughout legal markets, making quality-controlled options easier to find than ever.
- Long-lasting relief: Because RSO absorbs slowly through digestion or skin, its effects often last longer than smoked or vaped cannabis.
What Are the Risks and Side Effects of RSO?
RSO’s extreme potency creates real risks, mainly overwhelming psychoactive effects and legal restrictions in some areas.
- Overwhelming psychoactive effects: Rick Simpson CBD Oil warns that higher doses can cause anxiety, dry mouth, a fast heart rate, or red eyes, so avoid driving or operating machinery while impaired.
- Uncomfortable, though not dangerous, overconsumption: Hashtag Cannabis notes that taking too much RSO can cause couch lock, dizziness, anxiety, or nausea, though it is not toxic.
- Residual solvent concerns: Poorly purged homemade RSO may retain trace solvents. Always buy lab-tested products from licensed sources.
- Legal restrictions: WebMD notes that RSO remains illegal to buy in many places because of its high THC content, though legal cannabis states and countries sell it through licensed dispensaries.
- Drug interactions: THC can interact with certain medications, including blood thinners and sedatives. Pregnant or nursing individuals should avoid RSO entirely.
How Do You Dose RSO Safely?
Start with a dose about half the size of a grain of rice, then increase gradually over several weeks while tracking your response.
The golden rule of RSO dosing is simple: start low, and go slow. This schedule is suitable for beginners:
- Week 1: Take a tiny, half-grain-of-rice-sized dose three times daily, spread across morning, midday, and evening.
- Weeks 2â5: Double the dose roughly every four days, aiming for about one gram of RSO per day
- Ongoing: Keep a dosing journal that tracks amounts, timing, and effects, and share it with your healthcare provider.
Wait one to two hours after each dose before deciding whether to take more. This patience prevents accidental overconsumption. Taking RSO with a source of fat, such as a spoonful of peanut butter, can also improve absorption.
Body weight, prior cannabis experience, and individual metabolism all affect the ideal dose. Consult a knowledgeable healthcare provider before starting any RSO regimen, particularly for a serious medical condition.
How Does Rick Simpson’s Original 90-Day Protocol Work?
Rick Simpson’s original protocol calls for consuming 60 grams of RSO over 90 days, starting with a rice-grain-sized dose three times daily.
According to Simpson’s own published method, the regimen works as follows:
- Starting dose: A drop about the size of a grain of rice, taken three times a day, once every eight hours. Users can ingest it or apply it topically for skin conditions.
- Titration: Double the dose every four days.
- After week five: Increase to one gram of oil per day until reaching the full 60 grams.
Simpson originally designed this protocol for people using RSO to address cancer, so it represents an aggressive, high-dose approach rather than a general wellness routine. You and your doctor can discuss modifying the regimen to fit your health needs. Never smoke or vaporize RSO, since this method is considered unsafe for a raw, unrefined extract that still contains plant waxes and lipids.
Where Can You Buy Rick Simpson Oil?
Weed Wholesale Canada is your trusted source for premium Rick Simpson Oil (RSO) at competitive prices. We carefully source our RSO to deliver consistent potency, purity, and quality in every syringe. Choose from convenient 1g syringes for occasional use or 7g options for better long-term value. Whether you’re trying RSO for the first time or purchasing regularly, you’ll find affordable pricing without compromising quality.
Frequently Asked Questions About RSO
What Does RSO Feel Like?
RSO produces very strong, deeply calming effects because it packs high THC alongside the full range of plant compounds. Most people describe heavy, full-body relaxation, serious drowsiness, and a distinct feeling of euphoria. The experience feels more complete than a product containing THC alone, since terpenes and minor cannabinoids add to the effect.
Is Rick Simpsons Oil recommended for beginners?
Yes, but only very tiny doses. If you have a low tolerance, the psychoactive effects can feel intense, which is why the golden rule is to start with a tiny dose, no bigger than half a grain of rice, and wait to see how you feel before taking more.
Can You Smoke or Dab RSO?
No, you should never smoke, vape, or dab RSO. Producers make this oil specifically for oral or topical use, not for inhalation. RSO is a raw, unrefined extract that still contains plant waxes, fats, and chlorophyll, and heating these compounds to high temperatures for inhalation is harsh and potentially dangerous if any residual solvent remains.
How Should You Store RSO?
Store RSO in a cool, dark place, since heat and light break down cannabinoids over time. The refrigerator works well for longer-term storage.
What Are the Potential Side Effects of RSO?
Common side effects include intense drowsiness, dizziness, dry mouth, poor coordination, and red eyes. Higher doses may also cause temporary anxiety or paranoia in some users. The best way to avoid unwanted effects is to follow the “start low and go slow” rule.
Is RSO the Same as CBD Oil?
No, RSO is not the same as CBD oil. RSO is typically high in THC, the psychoactive compound in cannabis, while standard CBD oil contains little to no THC and produces no high. Some producers do make CBD-dominant versions of RSO from hemp, but traditional RSO refers to a THC-rich, full-spectrum extract.
Sources
Leafwell. (2026, April 10). Rick Simpson oil (RSO): Benefits, uses & risks. https://leafwell.com/blog/what-is-rick-simpson-oil-rso
Leafwell. (2025, October 23). Live resin vs. distillate: What’s the difference? https://leafwell.com/blog/live-resin-vs-distillate
National Cancer Institute. (n.d.). Cannabis and cannabinoids (PDQÂŽ)âHealth professional version. Retrieved July 14, 2026, from https://www.cancer.gov/about-cancer/treatment/cam/hp/cannabis-pdq
Siteman Cancer Center. (2022, November 29). Cannabis and cannabinoids (PDQÂŽ)âPatient version. https://siteman.wustl.edu/ncipdq/cannabis-and-cannabinoids-pdq-patient-version/
WebMD. (n.d.). Rick Simpson oil for cancer: Overview. Retrieved July 14, 2026, from https://www.webmd.com/cancer/rick-simpson-oil-for-cancer-overview
This article is for informational purposes only and does not constitute medical advice. Consult a licensed healthcare provider before using RSO or any cannabis product, particularly for treating a medical condition. Cannabis laws vary by location â check your local regulations before purchasing or using RSO.