After eight months of treatment with medical cannabis, 83-year-old São Paulo state deputy Eduardo Suplicy showed a 54.55% reduction in the Unified Parkinson's Disease Rating Scale (UPDRS) scores.

The result indicates a significant improvement in the motor symptoms of Parkinson's Disease (PD), such as mobility, bradykinesia, and hand tremors. The progress allowed the parliamentarian to regain essential daily functions, such as tying shoelaces, writing clearly, and holding a cup without spilling.

Reported secondary benefits include improved quality of life, sleep, communication, and reduction in depressive and anxious symptoms. No significant adverse effects were recorded throughout the treatment.

The results were published in July 2025 in the Brazilian Journal of Pharmacognosy, in a case study detailing Suplicy's clinical evolution. The dose used - 18.25 mg of tetrahydrocannabinol (THC) per day, divided into three administrations - was sufficient to reach the peak of physical well-being reported by the patient. Over time, the dose was increased to 20mg of THC per day, divided into breakfast, lunch, and dinner.

Graphic Summary:

Cannabis as an adjuvant therapy in Parkinson's treatment

Parkinson's Disease is a progressive neurodegenerative condition characterized by motor symptoms (such as tremors, rigidity, and postural instability) and non-motor manifestations. Before starting cannabis use, Suplicy only used Levodopa, a conventional medication for PD, but experienced severe motor symptoms, such as intense tremors and difficulty walking.

Cannabis was introduced as a complementary treatment. Despite using doses considered high of THC, the patient reported few adverse effects. This is partly due to the low bioavailability of oral administration - only 4% to 12% of THC reaches the bloodstream in this format, compared to up to 35% by inhalation. Suplicy did not experience sedation or lethargy, indicating no cannabinoid accumulation in the body.

The study's authors suggest that the data obtained may inaugurate a new line of research focused on the oral use of high doses of THC in the treatment of Parkinson's Disease and other neurological conditions. However, they emphasize the need for more robust studies, with larger samples and controlled methodology, to confirm the observed effects.

The case report was developed through a partnership between the entities: Medicinal Cannabis and Psychedelic Science Laboratory of the Federal University of Latin American Integration; Interdisciplinary Laboratory of Environmental Studies; 3 F Clinical Trials; Syrian-Lebanese Hospital; Cultivate Association and Flor da Vida Medicinal Cannabis Association