What's The Difference Between FECO and RSO?

Heard about Full Extraction Cannabis Oil and Rick Simpson Oil but not sure of the differences between the two?

RickSimpsonOil Picture
RickSimpsonOil Picture
RickSimpsonOil Picture

FECO and RSO are two very popular forms of cannabis oil. And while they might look identical, they have one big underlying difference. Keep reading to learn more about the difference between FECO and RSO and why one is slowly starting to overtake the other.

What are FECO and RSO: The Basics

Cannabis concentrates can come in an array of different textures, potencies, and types. FECO (Full Extract Cannabis Oil) and RSO (Rick Simpson Oil) are 2 different types of cannabis oil/extract that, despite looking almost identical, have some underlying differences that are important to understand if you plan on using either oil.

Full Extraction Cannabis Oil (FECO)

FECO is a highly concentrated cannabis oil with a thick, dark consistency. It is most typically sold in small plastic syringes to help facilitate doses for oral or topical use. Like RSO, FECO is a solvent-based extraction, meaning it is made using a substance (in this case alcohol) to dissolve the active compounds present in cannabis plant matter.

In most cases, the solvent used to make FECO is a simple high-strength grain alcohol like Everclear, for example. Grain alcohols are typically made using corn, rice, rye, wheat, or sugarcane and are suitable for making distillates for human consumption.

FECO can be made using both cannabis flower and trim and is considered a "full-spectrum" extract since it contains all the cannabinoids, terpenes, and other active compounds present in the cannabis plant (as opposed to broad-spectrum or isolate cannabis extracts, which typically have some compounds filtered out).

Check out our video on Ethanol Extraction for a quick overview of how to make FECO using the POT Herb Cooker.

Rick Simpson Oil (RSO)

Rick Simpson Oil, or RSO for short, is also a very high-potency cannabis extract that was originally created by Rick Simpson, a Canadian engineer who turned to cannabis because of work-related health issues and skin cancer.

Since discovering the powers of the cannabis plant in 2001, Rick Simpson has authored 2 books and traveled the world as a lecturer, speaker, and cannabis activist, all the while keeping his recipes and educational content free and in the public domain via his websites pheonixtears.ca and simpsonramadur.com.

RSO, like FECO, is a thick, dark oil. It is also typically sold in plastic syringes and taken orally and/or topically. It is, however, produced slightly differently—namely using naphtha (paint thinner) or isopropyl/ethyl alcohol as a solvent.


FECO and RSO share a similar appearance and potency. However, some stark differences in how each oil is produced have made one increasingly popular over the other. Below we take a closer look at the minor differences between FECO and RSO cannabis oil and highlight why they're important.


The main difference between FECO and RSO is the solvent used in their production. FECO is typically made with high-proof grain alcohol which is easier to purge and considerably safer than the naphtha or isopropyl/ethyl alcohol used to make RSO.

Naphtha and isopropyl/ethyl alcohol solvents are unfit for human consumption, hence extra care is needed to properly purge these solvents from the final extract to ensure a safe product.

Depending on the type of solvent used, RSO sometimes needs to be purged at high temperatures (heavy naphtha boils between 90-200°C) at which point some terpenes and other fragile cannabis compounds may be lost.


FECO and RSO look pretty much identical. Both have a dark, almost black colour and thick, sticky consistency similar to tar. If you choose to dilute RSO or FECO in alcohol to take it as a liquid tincture rather than a thick paste, both will take on a dark brown colour and a runnier consistency.


Both FECO and RSO are very high-strength cannabis oils that can contain anywhere between 60-90% cannabinoids. If possible, you could send the FECO or RSO you're taking to be tested to discover its exact potency.

Practical Applications

Given their high potency, FECO and RSO are typically used by people suffering from severe ailments. They can be taken orally by taking an amount of undiluted oil roughly equal to a grain of rice and applying it to the inside of the gums or under the tongue where it will slowly dissolve.

Similarly, you can also dilute RSO or FECO in alcohol and take them as you would a regular cannabis tincture. Finally, both FECO and RSO can be used topically by rubbing them onto an affected skin area, joint, or other parts of the body for localized relief.

What Are The Risks of FECO and RSO?

FECO is typically considered a fairly safe extract. RSO, on the other hand, is a little more concerning given that it's made with much harsher chemical solvents. If you're lucky enough to live in an area where cannabis is legally sold via licensed retailers, you should have little problems sourcing high-quality, safe FECO—just make sure to opt for a third-party-tested oil where possible.

Which Is Better: FECO or RSO?

The only difference between FECO and RSO is the solvents used to make them. Since FECO is made with grain alcohol, it is a much safer extract and has already begun replacing RSO in legal cannabis markets across the globe. If you're not able to buy FECO from a licensed retailer, don't fret—making FECO is super simple with the POT Herb Cooker by NOIDS, which streamlines the extraction process while ensuring you don't lose any cannabinoids, terpenes, or other compounds to combustion.