The Law

“There is a dichotomy between federal and state legislation for the use of cannabis. Federally, cannabis is labeled a schedule I substance,” she said. However, almost every state has passed laws allowing some form of cannabis use.

“I’m often asked how anyone can legally use cannabis if it is federally illegal,” Russell said. “It is true that federal law has supremacy over state law. However, states do adopt exemptions to federal law—the use of cannabis according to specific state laws and rules is one of those exemptions.”

State-implemented medical marijuana programs (MMPs) are exempt from federal law. For patients to enter an MMP and obtain marijuana from a dispensary, a certified healthcare practitioner must document a qualifying condition. Patients with cancer may seek that from APRNs or other prescribers on the cancer care team.

The Science

Moderate- to high-quality clinical evidence has emerged that establishes the efficacy of cannabis for:

• Certain therapeutic applications (i.e., cachexia, chemotherapy-induced nausea and vomiting)
• Pain from cancer or rheumatoid arthritis
• Chronic fibromyalgia pain
• Neuropathies from HIV/AIDS, multiple sclerosis, or diabetes
• Spasticity from multiple sclerosis or spinal cord injury
• Seizure frequency reduction

However, its safety has not been fully established by large-scale, randomized controlled trials, nor have moderate- to high-quality trials demonstrated its effectiveness for other applications. Improvements in other symptoms might be attributed to the more general effects of cannabis such as sedation, appetite stimulation, and euphoria, which may help mask symptoms, increase a subjective sense of well-being, and improve self-reported quality of life in some patients.

A major reason for the limited research on cannabis effectiveness or adverse effects is cannabis is a schedule I substance and therefore there are strict limitations on the use of cannabis in government-funded research.

Qualifying Conditions

Some uses of medical marijuana are supported by moderate- to high-quality research, but many others require more research to establish their effectiveness and safety, Russell said. However, a growing list of more than 70 conditions or symptoms across all the state programs can qualify a patient. The most common are:

• Amyotrophic lateral sclerosis (ALS)
• Crohn disease or irritable bowel syndrome
• Cachexia
• Cancer
• Epilepsy
• Fibromyalgia
• Glaucoma
• HIV or AIDS
• Multiple sclerosis
• Muscle spasms
• Nausea
• Pain
• Post-traumatic stress disorder

Side Effects of Cannabis

Side effects may vary depending on type of product and route of administration, Russell said. Particular considerations should be given to those with altered cognition, mania and predisposition to mania, and a propensity for abuse.

Additional considerations should be given to cannabis use in adolescents, those contemplating pregnancy, or those already pregnant or breastfeeding. No amount of cannabis use during pregnancy or adolescence is known to be safe.

Clinical Encounters

All discussions with patients considering medical marijuana should be based on informed and shared decision-making, without any judgment regarding the patient’s choice, Russell said. Necessary considerations regarding a patient’s treatment with cannabis include:

• Review all relevant medical records.
• Conduct a full assessment, including medical history and social determinants of health.
• Confirm the patient’s symptom or condition is on the state’s list of qualifying conditions.
• Discuss potential adverse effect based on the patient’s current condition and medications.
• Determine whether the patient is in a risk group.
• Discuss the patient’s personal preferences based on benefits and risks.
• Include the patient’s proxy, parent, or guardian (if the patient is incapacitated in decision making or is a minor) in decision-making.
• Record the patient’s subjective viewpoint of their quality of life.
• Evaluate the patient’s situational context, such as family and other important relationships, economic factors, access to care, and potential harm to others.

Because dosing is self-titrated, educate patients to “start low and go slow,” Russell said. Have them use a patient diary to track efficacy and side effects and commit to ongoing evaluation and monitoring with the APRN or prescriber.

The Evolving Role of Designated Caregivers

APRNs must also factor designated caregivers into the cannabis discussion and plan, Russell said. Most state regulations allow designated caregivers to register with the MMP to purchase cannabis products on patients’ behalf and assist with administration. Some states allow nurses, personal care attendants, home health aides, and others to become registered designated caregivers and administer therapeutic cannabis. A few states even allow school personnel to possess and administer medical marijuana to students.