Making Medicine from Cannabis: Extraction Methods Explained

How do we make the medicine? Cannabis contains hundreds of compounds that typically make up 15 to 40 percent of the plant's biological makeup. CBD, THC, and beta-caryophyllene are only a few of the known medicinal components. Extraction of these compounds is what creates effective medicine for patients, and there is no single method, each has trade-offs.

Solvents: polar and non-polar

Most methods involve a solvent, either polar (water-soluble) or non-polar (non-water-soluble). Non-polar solvents are desirable because the medicinal components we want are oils, while most undesirable compounds are water-soluble. Butane, propane, and heptane, along with CO2, are approved non-polar solvents. Hydrocarbons can be used together or separately (BHO, PHO) for extremely high-potency, high-quality extractions that, when purged properly, deliver the highest medicinal purity. CO2, an inert, non-toxic, non-flammable gas, is a close second on the purity scale.

Ethanol, isopropanol, acetone, and water are approved polar solvents. Non-polar solvents pull 50 to 80 percent of the medicinal material; polar solvents pull 90-plus percent, but ethanol, isopropanol, and acetone dissolve plant walls and remove everything, including undesirable impurities like chlorophyll, waxes, fats, and lipids. That extract is typically used for edible or topical products.

Solventless methods

Bubble hash. Extractors use water, ice, and agitation to harden the trichomes and shear them from the plant material. The trichomes are pumped through a series of mesh bags to separate them from residual plant matter. The result is typically smoked, vaped, ingested, or made into topicals.

Dry sift. A solventless technique that beats plant material against a mesh screen to separate the trichomes, which are collected through increasingly smaller micron screens. The end product is typically smoked or refined in a heat press.

Heat press (rosin). Heating plant material creates a viscous oil pressed through a screen, separating it from the plant matter. These highly concentrated oils, commonly called rosin, let patients ingest, vape, or apply the medicine topically.

Hot oil extraction. Any edible oil with a fat content, such as butter or hemp seed oil, can be heated with dried cannabis to extract compounds and infuse them into the oil's fats. Once strained, the infused oil is used for edible and topical products.

The goal: concentrated, consistent medicine

Each of these methods separates cannabinoids from the plant to create concentrated medicine. The right choice depends on the product, the patient, and the compounds you are trying to preserve. Matching method to goal is where experience earns its keep, and where the difference between a good product and a great one is made.