What is RSO? Rick Simpson oil revealed

what is rso

There are many forms of cannabis products on the market today. Whether it’s dabs, vape carts, CBD oil, edibles, salves, or good old flower, there are seemingly endless choices. In a world of long dispensary menus, some might ask: what is RSO?

Rick Simpson Oil (RSO) is a highly concentrated cannabis extract. It’s known more as a medical marijuana product due to its incredibly high levels of THC. While it is possible to make both THC and CBD RSO, the thick, viscous oil is typically associated with the former.

RELATED: Cannabis shown to be effective for severe pain

Named for its inventor, Rick Simpson, RSO is extremely versatile and touted for its potential benefits—particularly for cancer patients. If you’ve been wondering about the oil, this definitive guide has you covered.

what is rso
RSO is a thick oil known for its potency. Photo: Canva

What is RSO?

RSO is a potent whole-plant cannabis extract. Unlike some other concentrates, it contains a full spectrum of active ingredients, such as cannabinoids, terpenes, and other cannabis compounds.

The oil is incredibly thick and dark brown in color. It’s also remarkably potent—a starting dose is typically smaller than a grain of rice. RSO is consumed orally or topically; it is possible to smoke or dab RSO, but it can be a less than pleasant experience due to the consistency and flavor.

RELATED: The best cannabis products for sleep from across the country

Who is Rick Simpson?

Rick Simpson created his namesake oil (sometimes also called Phoenix Tears) after suffering from several conditions purportedly related to asbestos exposure. In 1997, the Canadian engineer was overcome while working in a hospital boiler room and fell from a ladder. He soon developed treatment-resistant tinnitus as well as dizzy spells and began consuming medical marijuana to ease his symptoms.

In 2003, a series of concerning moles appeared on Simpson’s skin. He was soon diagnosed with a form of skin cancer called basal cell carcinoma. After reading a study about the potential tumor-fighting abilities of cannabis, he began experimenting more with the plant—eventually creating Rick Simpson Oil.

Simpson applied his creation directly to his moles, covering them with a bandage for days at a time. He believed the RSO eradicated the cancer cells in his body and credited it with curing his cancer entirely. While the claim has never been scientifically proven, Simpson soon began mass-producing RSO and giving it away for free to patients in need, along with making his recipe available online for the world to use.

How is RSO made?

RSO is an alcohol-based cannabis extract. It is created by covering plant material with a solvent, preferably isopropyl alcohol, per Rick Simpson’s original recipe. The alcohol separates active compounds (including tetrahydrocannabinol/THC) from the plant. The solvent is then removed using heat.

The resulting oil is typically placed in a syringe for easy and accurate dosing. As mentioned above, the medical cannabis product is usually consumed orally or topically—some people even use suppositories.

rso syringe
The tip of an RSO syringe. Photo: Canva

Benefits of RSO

Studies on RSO itself are few and far between, but research on the benefits of THC is plentiful. A case study in 2013 saw RSO attributed to reducing the leukemic blast cell count in a teenage patient. However, other scientific inquiries into RSO are needed to confirm its unique potential.

Rick Simpson initially touted his oil as a way to treat cancer, and studies have shown cannabis may indeed have anti-tumor properties. At this point, the majority of medical marijuana use by cancer patients focuses on treating symptoms. 

A 2019 review of 30 studies on cannabis for chemotherapy-induced nausea showed the plant was more effective than many commercial antiemetics. Marijuana also has pain-relieving potential. Another study revealed that cannabis could be effective at managing cancer-related pain. And while many people battling cancer are turning to the plant, a cannabis knowledge disconnect remains between patients and their care providers—a major challenge for those seeking relief. 

RELATED: Could cannabis help improve your skin?

RSO dosing recommendations

Rick Simpson recommended patients consume 60 grams of RSO over the course of several weeks for maximum benefits. However, many people develop their own regimens. It’s important to note that RSO is incredibly potent and may not take effect for up to two hours after ingestion, so always start low and go slow.

Per Simpson’s protocol, patients should begin with one-quarter of a syringe drop (roughly half a grain of rice) every eight hours for three weeks. By week four, he directs the dose size to double to half of a dropper every eight hours.

In week five, Simpson recommends patients take a full syringe dropper the size of two grains of rice three times daily. Week six sees the dose increase to two dropper fulls (four rice grains). At this point, the dosing schedule continues for another six weeks or until all 60 grams are consumed. 

what is rso
Most people take RSO by mouth, but it can also be used topically and in suppositories. Photo: Canva

How to make RSO at home

Extracting cannabis oil like RSO at home is a somewhat simple process. However, safety measures should be taken. Always work in a well-ventilated room with fans blowing. Also, note that high temperatures are used so close monitoring is essential.

Materials needed:

  • One pound of dried cannabis flower (indica strains tend to work best)
  • Around two gallons of isopropyl alcohol
  • Two five-gallon buckets
  • Wooden spoon or yardstick
  • Electric rice cooker or crockpot
  • Cheesecloth
  • Funnel
  • Syringe

Step one:

Place the cannabis in one of the buckets. Gently muddle it a bit with the wooden spoon.

Step two:

Gently stir in alcohol until the plant material is completely covered. Reserve extra liquid for later. Mix for around three minutes.

Step three: 

Place cheesecloth over the second bucket and pour the cannabis alcohol mixture over, straining out the plant material. Place the wet material back in the first bucket.

Step four:

Repeat step two, adding the rest of the alcohol to bucket one. 

Step five:

Strain the mixture into the second bucket, this time discarding the plant material and cheesecloth afterward.

Step six:

Carefully pour the dark liquid into the rice cooker until roughly three-quarters full. Turn on the rice cooker and set it to 210-230°F.

Step seven:

As the liquid slowly evaporates, continue adding more of the mixture until it’s all been incorporated. Once the liquid is gone, the oil is ready.

Step eight:

Using the funnel, carefully pour the oil into syringes for accurate dosing.

RSO: powerful plant medicine

Rick Simpson Oil is a highly concentrated extract often reserved for medical cannabis patients. RSO packs quite the punch in a tiny package—its effects are among the strongest available on the market. Use it carefully.

Many people with cancer, chronic pain, and other debilitating conditions have praised RSO for its benefits, but research on the product remains limited. Since THC has shown great promise for a variety of ailments, RSO may be just what the doctor ordered for countless patients in need.


Rachelle Gordon

Rachelle Gordon is a cannabis journalist and Editor of GreenState.com. She began her weed writing journey in 2015 and has been featured in High Times, CannabisNow, Beard Bros, MG, Skunk, Cannabis and Tech Today, and many others. Rachelle currently splits her time between Minneapolis and Oakland; her favorite cannabis cultivars include Silver Haze and Tangie. Follow Rachelle on Instagram @rachellethewriter