Rick Simpson Oil (RSO) is a thick, concentrated cannabis extract typically sold in a syringe, and it can be used in three main ways: swallowed, held under the tongue, or applied directly to the skin. Each method produces different effects at different speeds, so the best approach depends on what you’re trying to get out of it. Because RSO is extremely potent, starting small is essential no matter which method you choose.
Swallowing RSO With Food
The most common way to use RSO is simply eating it. Squeeze out a piece no larger than half a grain of rice, place it on a small bite of food (something with fat like peanut butter, cheese, or a cracker with butter works well), and swallow. The fat helps your body absorb the cannabinoids more efficiently.
Effects take anywhere from 30 minutes to two hours to kick in, and they can last for several hours or longer. Because it passes through your digestive system and liver before reaching your bloodstream, the onset is slow but the experience tends to be more intense and sustained than other methods. This catches many first-timers off guard. If you don’t feel anything after an hour, resist the urge to take more. Wait at least two full hours before considering a second dose.
Sublingual Use for Faster Effects
If you want effects to arrive a bit sooner without inhaling anything, place a small amount of RSO under your tongue and hold it there for 30 to 60 seconds before swallowing. The tissue under your tongue absorbs cannabinoids directly into your bloodstream, bypassing the digestive process.
Expect to feel effects in roughly 45 minutes, with duration similar to oral ingestion. One thing to know: RSO is thick and has a strong, earthy taste that many people find unpleasant. Holding it under your tongue for a full minute takes some getting used to. The tradeoff is faster, more predictable timing compared to swallowing it with food.
Applying RSO to the Skin
RSO can also be used topically for localized issues. Apply a small amount directly to the affected area and cover it with a bandage to keep the oil in place. Replace the oil and bandage every three to four days. Once the skin looks healthy, continue applying for about two more weeks to support continued healing. Only about 4 to 5 grams total is typically needed for a full course of topical treatment.
When RSO stays on the skin, it doesn’t enter the bloodstream in meaningful amounts, so you won’t feel any intoxicating effects. Relief tends to arrive within minutes and stays localized to the area where you applied it. This makes topical use a good option if you want targeted support without the mental effects of THC.
The 90-Day Protocol
You may have seen references to a specific RSO dosing schedule: consuming 60 grams of RSO over 90 days, starting with a tiny dose and gradually working up to about 1 gram per day. This is the protocol Rick Simpson himself promoted, originally aimed at cancer patients.
It’s worth knowing that this protocol has no clinical approval, and most medical providers don’t recommend it. The idea came from early lab studies showing that THC could slow tumor growth in cell cultures and animal models, with some research finding that cannabis compounds stopped cancer cells from spreading while leaving healthy cells intact. But lab results and animal studies haven’t translated into reliable evidence that RSO treats cancer in humans. No clinical trials have confirmed the protocol’s effectiveness for that purpose.
That said, cannabis oils high in THC do have more established uses. They can help control nausea and vomiting during chemotherapy, manage pain, and improve appetite. Some CBD-containing oils, including those with THC, have also shown real benefits for controlling certain types of seizures in people with epilepsy.
How to Dose Safely
RSO is one of the most concentrated cannabis products available, so dosing requires patience. Start with a piece about half the size of a grain of rice. That sounds absurdly small, but with a full-spectrum extract this potent, even that tiny amount can produce strong effects, especially if you’re new to cannabis or have a low tolerance.
Stay at your starting dose for several days before increasing. Your body builds tolerance to THC over time, and what feels overwhelming in the first week often becomes manageable by the third. If you’re following any structured protocol, the general idea is the same: begin low, increase gradually, and let your body adjust at each step. There’s no benefit to rushing. Taking too much RSO won’t be dangerous in a life-threatening sense, but it can cause hours of uncomfortable drowsiness, anxiety, or disorientation.
Storing RSO to Keep It Potent
Heat, light, air, and moisture all degrade the cannabinoids and terpenes in RSO over time. For short-term storage (a few months), keep the syringe in a cool, dark spot like a pantry or cupboard, sealed tightly. A kitchen drawer away from the stove works fine.
If you’re storing RSO for longer, refrigeration extends the shelf life to one to two years. Freezing can preserve it for several years, potentially indefinitely. Frozen RSO becomes very thick and hard to work with, so let it thaw gradually at room temperature before trying to dispense it. Whatever you do, keep the cap on the syringe when you’re not using it. Air exposure is one of the fastest ways to lose potency.
Buying RSO: What to Look For
RSO is made by extracting cannabis compounds with a solvent, then evaporating the solvent away. The concern is that trace amounts of solvent can remain in the final product. Ethanol (the same alcohol in beer and wine) is considered a low-risk solvent, while other chemicals sometimes used in extraction, like methanol or benzene, are genuinely toxic even in small amounts.
If you’re purchasing RSO from a licensed dispensary, look for products that have been tested by a third-party lab. The certificate of analysis should confirm that residual solvents fall within safe limits. Ethanol, for instance, is permitted at concentrations below 5,000 parts per million, while more hazardous solvents like benzene are restricted to below 2 parts per million. You don’t need to memorize these numbers, but you should be able to see test results. If a product doesn’t have lab results available, that’s a reason to choose a different one.