On November 6, 2018, Missouri voters approved Amendment 2, which legalizes the use of medical marijuana for qualified patients with a physician's certification. The law went into effect on December 6, 2018.

 Patient licenses: Residents of Missouri may submit an application to the Department of Health and Senior Services for a patient registration card if they have been diagnosed with a qualifying condition and have received a certification from a state-licensed physician in good standing. A patient registration card must be recertified at least once a year.

Qualifying conditions: cancer, epilepsy, glaucoma, intractable migraines unresponsive to other treatment, conditions that cause persistent pain or muscle spasms (including MS, Parkinson’s disease, and Tourette’s syndrome), debilitating psychiatric disorders such as PTSD, HIV or AIDS, a chronic medical condition normally treated with prescription medication that can lead to dependence, when a physician determines that medical marijuana could be an effective and safer treatment, any terminal illness, hepatitis C, ALS, inflammatory bowel disease, Crohn’s disease, Huntington’s disease, autism, neuropathies, sickle cell anemia, Alzheimer’s disease, cachexia, and wasting syndrome.

Minor patients: Patients under the age of 18 may qualify for a patient registration card only with the written consent of their parent or guardian. Only a parent or guardian may serve as a minor patient’s caregiver. A parent or guardian must supervise the minor’s use of medical marijuana.

Visiting patients: Out-of-state patients who possess a valid registration card issued by their home state are afforded the same protections from civil and criminal liability as Missouri patients.

Physicians: Physicians who certify patients and assist them in obtaining a medical marijuana ID card are protected from civil and criminal liability and disciplining from state agencies.

Caregivers: In their application for a registration card, patients may designate up to one caregiver to assist them in accessing and using medical marijuana. Caregivers must have significant responsibility for managing a qualifying patient’s wellbeing. A caregiver may not assist more than three patients.

Possession limits: Patients and caregivers may possess up to one ounce of marijuana. With a separate cultivation ID card (with an annual fee of $100), they may cultivate up to six marijuana plants. Cultivation must take place in an enclosed, locked space that may only be accessed by the qualifying patient or caregiver. Two patients may share a single cultivation space, allowing a maximum of 12 plants in one space. There is an exception if one of the patients is also a caregiver, in which case there may be up to 18 plants in a single location.

Medical Cannabis Access: Amendment 2 sets forth a process for the Department of Health and Senior Services (DHSS) to develop rules and procedures to ensure safe access for patients through a regulated system of cultivation and sales. The department may establish purchase limits for patients, but this may be overridden if two physicians certify that a greater amount is needed.

The department is directed to accept marijuana facility applications and award licenses to medical marijuana businesses, including dispensaries, cultivation centers, testing facilities, and infused-product manufacturers. All facilities are required to implement a seed-to-sale tracking system. The department will begin accepting applications during 2019, according to a timeline outlined in Amendment 2. The department may limit the number of dispensaries, but there must be at least 24 within the state. Amendment 2 requires that all medical marijuana products made available to patients be cultivated within state boundaries.

Anti-Discrimination Protections: Patients may not be denied organ transplants on the basis of their status as a registered patient.

Localities: Local governments may not prohibit the establishment of marijuana facilities in their jurisdiction, but they may implement additional regulations (such as operating hours) and civil penalties that are not in conflict with the law. Marijuana facilities may not be located within 1,000 feet of a school, day care center, or church unless permitted by the locality.

Paraphernalia: Marijuana paraphernalia is protected under Amendment 2’s definition of “medical use.”

Taxes: Amendment 2 levies a 4% retail sales tax on medical cannabis. After retaining no more than 5% for actual collection costs, the remainder is to be deposited into the newly established Missouri Veterans Health Care Fund for veterans’ benefit including healthcare services, drug rehabilitation services, housing assistance, job training, and tuition assistance.