By Jeff Eckenrode

Quick Answer: FECO (Full Extract Cannabis Oil) and RSO (Rick Simpson Oil) are potent cannabis concentrates made using whole-plant extraction methods. Both contain a wide spectrum of cannabinoids and terpenes, but FECO is usually made with food-grade ethanol and is often meant for oral or sublingual use, while RSO is typically made with isopropyl alcohol and was originally intended for topical use.

At first glance, FECO and RSO look pretty similar: they are thick, they’re often black or dark brown in color and they’re both packed with cannabinoids.

Additionally, FECO and RSO are both types of full-spectrum extracts, which means they include not just THC or CBD, but a broad mix of other plant compounds like terpenes, flavonoids, and minor cannabinoids.

So what is the difference anyway?

What Is FECO?

FECO stands for Full Extract Cannabis Oil. It’s typically made by soaking cannabis flower in food-grade ethanol, which pulls out the cannabinoids, terpenes, and other beneficial compounds.

Once the plant material is strained out, the ethanol is evaporated off—leaving behind a thick, tar-like oil that can be eaten directly, taken under the tongue, or even added to food (start with a rice-grain-sized dose—it’s strong!).

FECO is often chosen by medical patients because it’s made with ingestible-grade solvents and is easy to dose accurately.

What Is RSO?

RSO stands for Rick Simpson Oil, named after the Canadian medical cannabis advocate who popularized it. Rick originally made the oil at home using isopropyl alcohol as a solvent—an effective method, but not one intended for internal consumption.

These days, many brands use food-grade solvents when making RSO for retail sale, but traditionally, it’s more associated with topical or external use.

Still, some users do ingest it, especially if they’ve sourced it from a brand that uses food-safe processes.

Why Use FECO or RSO?

People often reach for FECO or RSO when they want a long-lasting, full-bodied experience or a powerful, high-dose edible experience.

Whether you’re managing chronic pain, supporting wellness goals, or just want to explore whole-plant extracts, both options deliver:

Potent, full-spectrum effects

Easy to dose (just a tiny bit goes a long way!)

Versatile for different use methods (oral, sublingual, topical)

Just remember: these oils are STRONG. Start with a small amount (eg: half a grain of rice in size) and give it time to kick in before trying more (30-90 minutes)