Pharmaceutical Cannabis: FDA Approvals, Schedule III, and Pipeline Drugs

Pharmaceutical cannabis is a small group of prescription drugs, derived from or chemically related to the cannabis plant, that have been reviewed and approved by the U.S. Food and Drug Administration. There are four of them, and they are treated in law and medicine as ordinary prescription medications rather than as marijuana. The FDA has not approved the cannabis plant itself for any medical condition.¹

The Four FDA-Approved Drugs

Only one FDA-approved drug is extracted from the cannabis plant. The other three are synthesized in a laboratory.

Epidiolex (cannabidiol) is a highly purified CBD oral solution extracted from the cannabis plant. The FDA approved it on June 25, 2018, for seizures associated with Lennox-Gastaut syndrome and Dravet syndrome, and expanded its label in August 2020 to include tuberous sclerosis complex in patients one year and older. It contains no THC and does not produce euphoric effects.²³

Marinol (dronabinol) is a synthetic version of delta-9-THC, approved in 1985 for chemotherapy-induced nausea and vomiting, and later for anorexia associated with weight loss in AIDS patients.⁴

Syndros (dronabinol) is a liquid formulation of synthetic delta-9-THC with the same approved indications as Marinol.

Cesamet (nabilone) is a synthetic compound with a chemical structure similar to THC, approved for chemotherapy-induced nausea and vomiting.⁵

All four go through the same FDA pathway, but the source of the active ingredient matters for manufacturing and, historically, for how the Drug Enforcement Administration schedules the product.⁶

How This Differs from Medical Marijuana at a Dispensary

Both are sometimes called “medical cannabis,” but they are not the same thing. FDA-approved cannabinoid drugs have completed years of controlled clinical trials showing safety and efficacy for specific conditions, are manufactured to pharmaceutical standards for consistency and purity, and are dispensed by prescription through pharmacies. Products sold at state-licensed dispensaries are regulated by individual states, have not gone through FDA review, and can vary in potency, purity, and labeling accuracy.⁷

In states with medical marijuana programs, a healthcare provider does not write a traditional prescription. The provider certifies that the patient has a qualifying condition, and the patient buys products at a state-regulated dispensary. The FDA treats those unapproved cannabis products marketed for therapeutic use as unapproved new drugs.¹

Insurance follows the same divide. Epidiolex, Marinol, Syndros, and Cesamet can be covered by plans that include them on their formularies. Dispensary medical marijuana generally is not. New York, for example, has clarified that Medicaid covers office visits related to medical cannabis certification, but the cannabis products themselves are not a covered Medicaid benefit.⁸

Where Federal Scheduling Stands in 2026

The regulatory picture changed in late 2025 and 2026. On December 18, 2025, President Trump signed Executive Order 14370, “Increasing Medical Marijuana and Cannabidiol Research,” directing the Attorney General to complete rescheduling of marijuana from Schedule I to Schedule III “in the most expeditious manner.”⁹

On April 23, 2026, Acting Attorney General Todd Blanche placed two categories of marijuana products into Schedule III immediately: FDA-approved drug products containing marijuana, and marijuana products covered by a qualifying state-issued medical marijuana license.¹⁰ Blanche invoked authority under 21 U.S.C. 811(d)(1), which allows rescheduling to satisfy U.S. obligations under the Single Convention on Narcotic Drugs without going through the standard scheduling procedures.¹¹

Bulk marijuana, marijuana extracts, and THC that is not contained in an FDA-approved drug or covered by a state medical license remain in Schedule I.¹¹ The broader rescheduling of marijuana generally is still proceeding through a formal administrative hearing process; the DEA scheduled those hearings to begin June 29, 2026, in Arlington, Virginia, with a conclusion date no later than July 15, 2026.¹²

Rescheduling to Schedule III does not legalize cannabis at the federal level, does not create a comprehensive federal framework for recreational use, and does not guarantee insurance coverage.

What Schedule III Actually Changes

The most concrete change is tax. Under Section 280E of the Internal Revenue Code, businesses that traffic in Schedule I or II substances cannot deduct ordinary business expenses. A cannabis company with $1 million in revenue and $250,000 in operating costs could face taxable income of $350,000 under Schedule I rules, compared to $100,000 if those expenses were deductible under Schedule III.¹¹

The shift is also expected to ease clinical research by reducing DEA-related burden, and to give banks, insurers, and pharmaceutical developers more confidence to work with cannabis products.

How Cannabinoid Drugs Get Approved

Pharmaceutical cannabis products follow the same pathway as any other drug. Developers submit an Investigational New Drug application to the FDA’s Center for Drug Evaluation and Research before running clinical trials. If trials show safety and efficacy, the company files a New Drug Application for marketing approval.⁶

For decades, Schedule I status added a second track. Researchers needed a site-specific DEA investigator registration, DEA approval of the study protocol, and often had to source their cannabis through the National Institute on Drug Abuse supply program. The Medical Marijuana and Cannabidiol Research Expansion Act (H.R. 8454), signed into law on December 2, 2022, was aimed at those bottlenecks. It eliminated duplicative DEA review of research protocols already approved by the FDA or NIH, imposed 60-day deadlines on the DEA to act on researcher registrations, expanded the number of authorized cannabis manufacturers for research supply, and required the DEA to register applicants seeking to manufacture cannabis for the commercial production of FDA-approved drugs.⁴¹³ The law also explicitly allows physicians to discuss the potential benefits and risks of cannabis with patients.

Plant-derived cannabinoid drugs carry an additional burden. A botanical drug must show that the combination of molecules in the product offers efficacy superior to its individual components, and that its safety profile is acceptable. Keeping chemical composition consistent across batches of a plant extract is harder than manufacturing a single synthetic molecule.¹⁴

Epidiolex, in Detail

Epidiolex is the most commercially significant pharmaceutical cannabis product and shows how the approval process works for a plant-derived cannabinoid. Developed by GW Pharmaceuticals in the United Kingdom, it was the first medicine extracted directly from cannabis to be approved by the FDA. Approval in June 2018 followed a unanimous positive recommendation from an FDA advisory committee and was supported by four randomized, double-blind clinical trials showing significant reductions in seizure frequency.³

Because it was derived from cannabis, Epidiolex required a DEA scheduling action before it could be sold. In September 2018 the DEA placed it in Schedule V, the least restrictive category.¹⁵ In April 2020 the DEA descheduled it entirely, removing it from the controlled substances list.¹⁶

Jazz Pharmaceuticals acquired GW Pharmaceuticals in 2021 in a deal valued at $7.2 billion, driven largely by Epidiolex’s commercial potential.¹⁷ Sales grew from roughly $510 million in 2020 to $972 million in 2024 and $1.059 billion in 2025, when the company described the product as having reached “blockbuster status.”¹⁸

What’s in the Pipeline

Several cannabinoid drugs are in development, targeting conditions well beyond epilepsy and chemotherapy-related nausea.

Nabiximols (Sativex)

The most prominent candidate not yet available in the United States is nabiximols, marketed as Sativex abroad. It is an oromucosal spray containing roughly equal parts THC and CBD (2.7 mg and 2.5 mg per spray) and is approved in 29 countries for spasticity associated with multiple sclerosis.¹⁹ Jazz Pharmaceuticals has been running a U.S. registrational program aimed at supporting a New Drug Application, though one Phase 3 trial (RELEASE MSS1) failed to meet its primary endpoint. Additional Phase 3 trials are ongoing.²⁰

Other Clinical-Stage Candidates

The broader cannabinoid pipeline spans pain, neurological disorders, obesity, and oncology. Among the more advanced programs are AP-707, a Phase III candidate from Apurano Pharmaceuticals for back pain; IGC-AD1, a Phase II compound from IGC Pharma for agitation in Alzheimer’s-related dementia; and CRB-913, a Phase I obesity drug from Corbus Pharmaceuticals.²¹

Setbacks are common. ZYN002 (Zygel), a transdermal CBD gel developed for Fragile X syndrome, failed its pivotal Phase 3 trial (RECONNECT) in September 2025 after a higher-than-expected placebo response. It was the drug’s second Phase 3 failure. Harmony Biosciences, which acquired the drug from Zynerba Pharmaceuticals in 2023, has not announced next steps.²²

Known Risks and Side Effects

The FDA-approved cannabinoid drugs carry documented side effects. For Epidiolex, adverse effects occurring in at least ten percent of patients include drowsiness, fatigue, decreased appetite, diarrhea, rash, insomnia, and elevated liver enzymes.³ The FDA has flagged the potential for liver injury specifically, noting it is manageable under medical supervision but dangerous with unsupervised use.²³

CBD can interact with other medications, particularly those metabolized by the liver and drugs that slow brain activity, such as treatments for anxiety or insomnia. Animal studies have raised concerns about male reproductive toxicity, though whether those findings apply to humans is unknown.²³ The FDA continues to collect adverse event reports through MedWatch and has acknowledged data gaps on long-term safety, particularly in children, the elderly, and pregnant or breastfeeding women.¹

The Hemp Carve-Out

One further boundary matters when reading about cannabinoid products. The 2018 Farm Bill removed hemp — cannabis containing no more than 0.3 percent delta-9 THC on a dry weight basis — from the Controlled Substances Act, but it did not change the status of marijuana or most cannabis products. The FDA has maintained that adding CBD or THC to food, or marketing CBD as a dietary supplement, is illegal regardless of whether the source plant is classified as hemp.¹ The over-the-counter CBD products sold in general retail are not pharmaceutical cannabis and are not FDA-approved drugs.

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