How to use cannabis oil
Measure the dose first. Cannabis oil comes in a dropper, a capsule, or a metered spray. Hold the dose under your tongue for 60 to 90 seconds, or swallow it. Wait two hours before taking more. Sublingual oil starts working in 15 to 45 minutes. Swallowed oil starts in 30 to 120 minutes. Both last 4 to 8 hours.
Start low. For THC, 1 to 2 mg is a common first dose. For CBD, labels often start at 10 to 25 mg. A standard dropper holds about 1 mL, which can contain 5 mg or 50 mg depending on the bottle. Read the milligram count per mL, not the total printed on the front of the bottle.
Read the label before the first dose
- Milligrams of THC and CBD per mL and per container.
- Carrier oil: MCT oil, olive oil, hemp seed oil, or ethanol.
- Batch number and test date.
- A lab report or QR code. Ask the seller for the report if the label has none.
Hemp products sold under federal law test at or below 0.3% THC on a dry weight basis. That limit is not zero THC. Several units in a day can add up. A full bottle of a high-concentration tincture can hold 500 mg to 1,500 mg of CBD and 5 mg to 50 mg of THC.
Pick a method
- Sublingual dropper: hold under the tongue, then swallow. Onset 15 to 45 minutes.
- Capsule or edible oil: swallow with food. Onset 30 to 120 minutes. Effects last longer.
- Topical oil: rub into skin. Little reaches the bloodstream. Use for local pain, not for a full-body effect.
- Inhalation or vaporizing: effects in minutes. This route carries lung risk, and vapor cartridges often list THC content without a dose per puff.
Eat before or after a capsule dose, but keep it the same each time. Food, especially fat, changes how much THC the body absorbs.
Side effects and drug interactions
THC can cause dry mouth, red eyes, a faster heart rate, anxiety, and short-term memory problems. CBD can cause sleepiness, loose stools, and raised liver enzyme levels. CBD blocks the CYP3A4 and CYP2C19 enzyme pathways. That can raise blood levels of warfarin, clobazam, and some antiseizure drugs. Talk to a pharmacist if you take a blood thinner, a seizure drug, or a transplant drug.
Do not drive for at least 4 hours after a THC dose. THC stays detectable on a urine screen for days to weeks after one use. The window depends on dose, frequency, and body fat.
Storage and convenience
Keep the bottle away from light and heat. Tighten the cap. A sealed bottle holds potency for about 12 to 24 months from the production date. Cold makes some oils cloudy. They clear at room temperature. Do not mix oil into a hot drink. Heat and dilution make the dose hard to track.
Format drives the buying decision. Pre-measured capsules and metered pens remove the counting step. A dropper costs less per milligram but needs a steady hand and a mirror. Capsules cannot be split for a dose below the capsule size. Tinctures allow a 0.25 mL change, which matters at low doses. Pick the format that matches the dose you plan to take, not the one with the best packaging.
Legal status
The FDA has approved one CBD drug, Epidiolex, for seizures tied to Lennox-Gastaut syndrome, Dravet syndrome, and tuberous sclerosis complex. The FDA has also approved THC-based drugs for nausea and appetite loss. Other cannabis oils sold at retail are not FDA approved. State law controls the sale. Rules differ on THC limits, minimum age, and possession amounts. Long-term effects of daily CBD oil are not known.