Cannabis doesn’t fit neatly into a single classification. Depending on who’s doing the classifying and why, it’s simultaneously a Schedule I controlled substance under U.S. federal law, a plant in the hemp family, and a drug that crosses three pharmacological categories at once. The answer to “what is cannabis classified as” depends on whether you’re asking a lawyer, a botanist, a pharmacologist, or an international regulatory body.
U.S. Federal Drug Scheduling
Under the Controlled Substances Act, cannabis (referred to as “marijuana” in federal law) is currently a Schedule I substance. That’s the most restrictive category, reserved for drugs the government considers to have high abuse potential and no accepted medical use. Other Schedule I substances include heroin and LSD.
This classification has been in place since 1970, but it’s actively being challenged. The Department of Justice published a formal proposal in 2024 to move cannabis from Schedule I to Schedule III, which would place it alongside drugs like testosterone and certain codeine formulations. Schedule III substances are recognized as having medical value and a lower potential for abuse. As of early 2025, the DEA began formal hearings on the rescheduling proposal, with proceedings commencing on January 21, 2025. The process involves multiple rounds of testimony and evidence review, so a final decision could take months or longer.
The Hemp vs. Marijuana Line
Federal law draws a sharp legal distinction within the cannabis plant itself, and it comes down to one number: 0.3 percent THC by dry weight. Cannabis containing 0.3 percent or less THC is legally classified as hemp and was removed from the Controlled Substances Act by the 2018 Farm Bill. Cannabis containing more than 0.3 percent THC remains classified as marijuana and is still federally controlled.
This threshold matters in practice because it determines whether a cannabis product can be legally grown, sold, and shipped across state lines. A National Institute of Justice study has flagged concerns about inaccurate labeling, with some products sold as hemp actually exceeding the 0.3 percent THC limit. Botanically, hemp and marijuana are the same plant species. The distinction is purely chemical and legal.
International Drug Classification
Globally, cannabis falls under the United Nations Single Convention on Narcotic Drugs, where it’s listed in Schedule I alongside cannabis resin and its extracts. Until recently, cannabis also sat in Schedule IV of the Single Convention, the most restrictive tier reserved for drugs considered particularly dangerous with limited therapeutic value. In 2020, the UN Commission on Narcotic Drugs voted to remove cannabis from that Schedule IV listing, a recognition that the plant has medical applications. It remains in Schedule I of the Convention, which still subjects it to international controls but without the harshest restrictions.
Pharmacological Classification
This is where cannabis gets genuinely unusual. Most drugs fall into one pharmacological category. Cannabis falls into three: depressant, stimulant, and hallucinogen. The Australian Department of Health specifically lists cannabis as appearing in all three categories, and the reason comes down to the wide range of effects THC and other compounds in the plant produce.
As a depressant, cannabis slows communication between the brain and body. This is why it can impair coordination, slow reaction times, and create a feeling of deep relaxation. These are the effects most people associate with being “high.”
As a stimulant, it can increase heart rate, raise blood pressure, and in some people cause agitation or make it difficult to sleep. These effects are more common with certain strains or higher doses, and they’re part of why some users feel anxious or wired rather than calm.
As a hallucinogen, cannabis can alter sensory perception. Colors may seem brighter, time may feel distorted, and at high doses, some users experience mild visual or auditory distortions. These effects are typically much subtler than those produced by classic hallucinogens like psilocybin, but they’re real and well-documented enough to earn cannabis the classification.
Which category dominates in any given experience depends on the dose, the specific chemical profile of the product, and the individual user’s biology.
Botanical Classification
In plant science, cannabis belongs to the family Cannabaceae, commonly called the hemp family. Its closest well-known relative is hops, the plant used in brewing beer. The USDA classifies it as a flowering plant and a dicotyledon (a plant whose seeds sprout with two initial leaves).
The full taxonomy runs: Kingdom Plantae, Family Cannabaceae, Genus Cannabis, Species Cannabis sativa L. What most people think of as “indica” and “sativa” are not separate species. They’re subspecies of the same plant. The USDA recognizes Cannabis sativa subsp. sativa and Cannabis sativa subsp. indica. A third variety, often called ruderalis, is sometimes discussed separately but is generally treated as part of the same species. The popular idea that indica and sativa produce reliably different effects (relaxing vs. energizing) has more to do with the specific mix of cannabinoids and terpenes in a given plant than with its subspecies classification.
Medical Classification
Despite its Schedule I status, several cannabis-derived or cannabis-related medications have full FDA approval. The most notable is Epidiolex, which contains purified CBD extracted from the cannabis plant. It’s approved for treating seizures associated with two severe forms of childhood epilepsy in patients two years and older.
Three additional approved medications use synthetic versions of THC or closely related compounds. Two of these (sold under brand names Marinol and Syndros) treat nausea from cancer chemotherapy and appetite loss in AIDS patients. A third (Cesamet) uses a synthetic compound structurally similar to THC and is also approved for chemotherapy-related nausea. These approvals create a notable contradiction: the federal government classifies cannabis as having no accepted medical use while simultaneously approving medications derived from or modeled on its active compounds.
If the proposed rescheduling to Schedule III goes through, it would formally resolve that contradiction by acknowledging cannabis has accepted medical applications with a moderate potential for dependence. It would also open the door to easier research access, since Schedule I status currently requires special federal authorization for any scientific study involving the plant.