Medical Cannabis Access Barriers May Undermine Epilepsy Treatment Outcomes

For many people living with refractory epilepsy, every seizure prevented can mean greater independence, improved quality of life, and a reduced risk of serious injury. While cannabis-based medicines have attracted increasing attention as a treatment option for patients whose seizures do not respond to conventional therapies, one of the biggest challenges may not be whether these products work, but whether patients can consistently access them.

A 2026 real-world study¹ from Brazil not only adds to the growing body of evidence suggesting cannabis-based products help many people with treatment-resistant epilepsy, but the research also delivers an important public health message; that interruptions in treatment caused by financial or administrative barriers are associated with significantly poorer outcomes, underscoring that access to medicine can be just as important as the medicine itself. Let’s dive into the research and what needs to happen to help patients better access necessary cannabinoid therapies.

Who the Researchers Studied

The study evaluated patients participating in Brazil’s public healthcare system through the Canabidiol–SUS Project. Unlike randomized clinical trials, which are conducted under tightly controlled conditions, this research examined how cannabis-based therapies perform in everyday clinical practice.

Researchers interviewed 91 patients who had received cannabis-based products between 2017 and 2022 through Brazil’s public health system. The average age of participants was 19.5 years and just over half were male. Because the study focused on individuals with refractory epilepsy, patients whose seizures remain uncontrolled despite multiple conventional medications, it represents a population with particularly limited treatment options. Researchers defined treatment success as a patient reporting at least a 50% reduction in seizure frequency, a benchmark commonly used in epilepsy research.

Cannabis Caused Meaningful Seizure Reduction

The findings of the study were encouraging. Overall, 70.3% of participants reported experiencing at least a 50% reduction in seizure frequency while using cannabis-based products. For many epilepsy specialists, achieving this level of seizure reduction represents a clinically meaningful improvement that can substantially affect daily functioning and quality of life.

The results became even more striking when researchers compared current cannabis users with patients who had discontinued treatment. Among participants who were still using cannabis-based products at the time of the interview, 94.7% met the responder threshold, compared with 57.1% of former users.

Although the study cannot prove that continued cannabis use directly caused these better outcomes, the difference raises important questions about the role that treatment continuity may play in managing refractory epilepsy.

Longer Treatment Appeared Linked to Better Outcomes

Another notable finding involved treatment duration. Patients who had remained on cannabis-based therapy for more than 12 months were substantially more likely to report that treatment was effective. Statistical analysis found an odds ratio of 23.79 for perceived effectiveness among long-term users.

However, the researchers were careful not to overstate this observation. Because the study was cross-sectional, it cannot establish cause and effect. The authors specifically caution that reverse causation and survivorship bias may explain part of this association. In other words, patients who benefited from treatment were naturally more likely to continue using it, while those who experienced little benefit may have stopped earlier. That distinction is important because the research cannot merely assume that simply remaining on treatment longer guarantees better outcomes.

Safety Profile Was Generally Acceptable

As with virtually every medical therapy, cannabis-based products were not free of side effects. Overall, 51.6% of participants reported experiencing adverse events, although most were described as mild to moderate. The most commonly reported side effects included:

• Sleep disturbances
• Mood or neurological changes
• Gastrointestinal symptoms

While adverse events affected more than half of participants, the researchers concluded that the overall safety profile remained acceptable. For patients with severe, treatment-resistant epilepsy, clinicians often weigh these manageable side effects against the potentially devastating consequences of uncontrolled seizures, making individualized treatment decisions especially important.

Access Barriers to Medical Cannabis

Although the seizure reduction data attracted attention, perhaps the study’s most significant contribution extends beyond the pharmacology of cannabis itself. Researchers found that patients who discontinued treatment because of access barriers experienced significantly lower odds of reporting treatment effectiveness. These barriers included financial challenges as well as administrative obstacles that interrupted patients’ ability to obtain cannabis-based products consistently.

The findings suggest that inconsistent access may reduce the real-world effectiveness of cannabis therapy, not necessarily because the medicine loses its therapeutic potential, but because treatment interruptions from financial and institutional barriers can make seizure control far more difficult to maintain. For chronic neurological conditions like epilepsy, consistency is often essential. Interruptions in medication can increase seizure frequency, complicate treatment planning, and reduce overall disease management, in turn reducing the patient’s quality of life.

Why Product Consistency Matters

The study also highlights another important issue facing medical cannabis patients worldwide: product consistency. Unlike many conventional pharmaceuticals, cannabis-based medicines can vary considerably in cannabinoid concentrations, formulations, and manufacturing standards depending on the product being used. Maintaining consistent treatment becomes more challenging when patients are forced to switch products due to cost, availability, or administrative delays.

The authors note that product heterogeneity should be considered when interpreting the findings, as different formulations may produce different therapeutic responses. This also reinforces the importance of reliable supply chains, standardized manufacturing practices, and healthcare systems that allow patients to maintain continuity with the therapies that work best for them.

Final Thoughts

Medical cannabis continues to show promise as a treatment option for people living with epilepsy, particularly for patients who have exhausted conventional therapies. This Brazilian study adds meaningful real-world evidence by showing that many patients reported substantial reductions in seizure frequency while experiencing an acceptable safety profile.

Perhaps even more importantly, the research reminds us that effective treatment depends on more than clinical efficacy alone. Financial hardship, administrative delays, inconsistent product availability, and interruptions in therapy may all undermine patient outcomes, even when an effective and often life changing medicine exists.

That lesson extends well beyond epilepsy. Patients living with chronic pain, multiple sclerosis, cancer, PTSD, inflammatory conditions, epilepsy, and many other illnesses increasingly rely on medical cannabis as part of their treatment plans. Yet many continue to face high out-of-pocket costs and limited access that place these therapies out of reach. As medical cannabis programs continue to evolve, improving affordability, ensuring product consistency, and reducing barriers to continuous treatment may prove just as important as developing new cannabis-based medicines themselves.

References:

^{1. Mariana Dias Lula, Ronaldo Portela, Daniel Marques Mota, Juliana Álvares-Teodoro, Maria Laura Silva, Augusto Afonso Guerra-Júnior, Cristina Mariano Ruas, Effectiveness and Safety of Cannabis-Based Products for Refractory Epilepsy From Real- World Evidence, Clinical Therapeutics, 2026, , ISSN 0149-2918, https://doi.org/10.1016/j.clinthera.2026.06.006}