Rick Simpson Oil (RSO) Guide
Rick Simpson Oil is a high-potency, full-spectrum cannabis extract developed for therapeutic use — not recreational consumption and not to be confused with standard cannabis oil.
What RSO Is and Where It Comes From
Rick Simpson Oil is named after Rick Simpson, a Canadian cannabis activist who claims to have treated his own skin cancer with a concentrated cannabis extract in 2003. He subsequently advocated for the protocol widely, offering free oil to cancer patients and documenting cases of apparent improvement. RSO is not a patented or commercially standardized product. The name refers to a preparation method: a full-plant cannabis extraction using hydrocarbon or alcohol solvents to produce a thick, dark, highly concentrated oil containing the full spectrum of cannabinoids, terpenes, and plant compounds. THC content typically ranges from 50-90% depending on the starting material and extraction efficiency. The medical claims associated with RSO are contested. While cannabinoids show promising results in laboratory and early clinical studies for certain cancer types and other conditions, RSO has not been approved by any regulatory body for cancer treatment. The evidence base consists primarily of anecdotal reports and preliminary research. Patients considering RSO should do so under medical supervision and not as a replacement for conventional treatment without physician guidance. For a full understanding of cannabis in medical contexts, our cannabis dosing guide provides the framework for responsible consumption, and our effects guides cover what different preparations can realistically provide.
RSO Dosing Protocol
The traditional RSO dosing protocol associated with Rick Simpson is a 12-week graduated program starting at extremely low doses and building to a full gram per day. This gradual approach allows tolerance to develop for the very high THC content. Week 1-2: Three doses per day of approximately 0.05ml each (about the size of a grain of rice). Total daily dose: 0.15ml. At 60% THC, this equals approximately 90mg THC per day — already a substantial dose by any recreational standard. Weeks 3-5: Double the dose every four days until reaching 1g per day. This is an extremely high THC intake by any medical cannabis standard and will produce profound psychoactive effects. Simpson's protocol acknowledges this and recommends accepting sedation as part of the therapeutic process. Weeks 6-12: Maintain at 1g per day (60g total over the treatment period). For ongoing maintenance after the initial 12 weeks, typical protocol recommends 1-2ml per day. This protocol is not appropriate for recreational use, for beginners, or for anyone without medical supervision when using therapeutic intent. The escalating doses will produce tolerance, cognitive impairment, and significant psychoactive effects throughout. Always consult a healthcare provider before undertaking any RSO protocol for medical purposes.
How to Use RSO
RSO is most commonly consumed orally — a small amount placed under the tongue (sublingual) or swallowed directly. The thick, syrupy consistency is dispensed from a blunt-tip oral syringe. A dose the size of a grain of rice is a typical starting amount. Sublingually, RSO onset is 15-45 minutes. Swallowed, onset is 30-90 minutes due to digestive processing, but the duration of effects extends to 6-8 hours or more. The liver conversion to 11-hydroxy-THC makes swallowed RSO especially potent and long-lasting. RSO can also be applied topically to skin conditions — the original Rick Simpson application was for skin cancer lesions. Topical RSO is applied directly to affected skin and covered with a bandage, changed daily. Topical application does not produce psychoactive effects in most users because skin is a poor absorber of THC without specialized penetration enhancers (unlike our transdermal patches guide which use active permeation technology). RSO can be mixed into food or dissolved in warm cooking fat. Because of its very high potency, any culinary use requires extreme caution with dosing — a typical dose of 0.05-0.1ml of RSO added to a batch of cookies changes their potency dramatically.
Safety Considerations for RSO Production
Home production of RSO carries serious safety risks that must be respected. The primary danger is solvent fire and explosion. Ethanol and naphtha are both highly flammable. The evaporation step produces solvent vapors that can ignite from a spark, static electricity, or any open flame in the area. Always evaporate solvent outdoors in a well-ventilated area, far from any ignition sources. Use only electric heat sources (electric rice cooker, electric hot plate) — never gas flame. Keep a fire extinguisher nearby. Never smoke or allow open flames within 10 meters of the evaporation process. Ethanol is safer than naphtha for home production because it is a food-grade solvent. Naphtha (lighter fluid or similar petroleum solvents) requires more rigorous complete evaporation to ensure no residual solvent remains in the final product. Residual naphtha in RSO is toxic. If using naphtha, test for residual solvent by placing a small drop on paper — if it evaporates without residue, the extraction is clean. Commercial cannabis extraction uses CO2 or pharmaceutical-grade ethanol under controlled conditions. For users seeking the therapeutic benefits of concentrated cannabis without the risks of home extraction, commercial RSO and full-spectrum cannabis extracts are increasingly available in legal cannabis markets. These products are laboratory-tested for both potency and residual solvent levels, providing a safer and more reliable option.
Step-by-Step Guide
RSO protocol specifies indica-dominant strains for sedative, anti-tumor properties. 450g of cannabis is the traditional starting material for a full treatment protocol.
Place cannabis in a large container. Cover with food-grade ethanol (or naphtha — though ethanol is safer). Stir for 3-4 minutes.
Pour through a strainer to remove plant matter. Repeat the solvent wash a second time with fresh solvent.
In a well-ventilated outdoor area or fume hood, gently heat the liquid (electric rice cooker or water bath) to evaporate the solvent. Never use open flame.
Continue heating on lowest setting until the oil becomes thick and dark. A few drops of water help evaporate remaining solvent. The finished RSO is dark, syrupy, and very thick.
Draw the warm RSO into blunt-tip oral syringes for precise dosing. Allow to cool — RSO thickens significantly at room temperature.
Week 1: 3 doses of 0.05ml (about a grain of rice) daily. Gradually increase over 12 weeks to 1ml per day.
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FAQ: Rick Simpson Oil
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Written by Marcus Webb, Cannabis Culture Writer. Published 2025-10-13.