The use of cannabidiol (CBD) is associated with “statistically significant reductions” in blood pressure among patients, according to an investigation conducted by researchers affiliated with University College London. The researchers reached their conclusion after a systematic review of clinical trial data and published their findings in the Journal of Cannabis Research.

“A systematic search of PubMed, Web of Science, Scopus, and Medline was conducted in September 2024. Eligible studies were randomised controlled trials (RCTs) involving oral CBD administration in normotensive or hypertensive adults, with blood pressure as an outcome.” the researchers wrote. “Four RCTs involving 120 participants met the inclusion criteria. Studies varied in CBD dose (225–600 mg/day), duration (two hours to 5 weeks), and participant health status. An association was observed between CBD dosage (mg/day) and reductions in blood pressure indicators, with greater reductions occurring at higher doses. All four studies reported statistically significant reductions in systolic blood pressure compared to placebo, particularly under stress or during sleep.”

“The strongest effects were observed with acute administration of the highest-dose studies of 600 mg/day. Side effect severity was generally mild to moderate, including nausea, diarrhoea, and fatigue. No serious cardiovascular events were reported.” the researchers found.

“Oral CBD may reduce blood pressure amongst healthy and hypertensive individuals, particularly under stressful conditions and during sleep.” the researchers concluded. “Larger, longer-term trials with homogeneous supplementation strategies and bioavailability measures are needed to determine CBD’s therapeutic role in blood pressure management.”

This recent study conducted in the United Kingdom adds to a growing body of research indicating that CBD may be an effective treatment for high blood pressure. According to international researchers, it is estimated that about 1.4 billion adults globally aged 30–79 years old have high blood pressure (hypertension), which represents roughly 33% of the population in that age range.

A team of academic and health researchers based in Split, Croatia, previously conducted a clinical trial that examined the use of cannabidiol and how it impacts blood pressure levels in patients with hypertension. The trial’s findings were published in the European Heart Journal.

“The trial was designed as a triple-blind randomized crossover trial. A total of 70 patients with primary hypertension were included. Exclusion criteria included the presence of significant comorbidities, smoking (tobacco and CBD), pregnancy, and BMI ≥ 35 kg/m2.” the researchers stated about their methodology.

Each patient who participated in the clinical trial was randomly assigned either cannabidiol or “placebo-matched capsules” for five weeks. Patients were then “crossed over to alternate therapy (CBD or placebo)” and assessed via regular visits, during which “venous blood samples were obtained from each patient.”

“After 5 weeks of CBD supplementation, 24h systolic and diastolic BP dropped for ~4 mmHg and ~3 mmHg, respectively. No such change was observed following 5-week course of placebo. The reduction in BP was accompanied by reduction in serum catestatin and urotensin-II levels.” the researchers found.

A French researcher previously concluded that both current and lifetime cannabis use are associated with lower blood pressure levels after assessing the relationship between cannabis use and blood pressure among a population-based cohort of over 91,000 subjects. The research findings were recently published in the journal Nature: Scientific Reports.

The investigator reported: “In adjusted covariates models, lifetime heavy cannabis use was associated with decrease in both SBP [systolic blood pressure], DBP [diastolic blood pressure], and PP [pulse pressure] in both genders, but with a higher effect among women. … Current cannabis use was associated with lower SBP levels in men and in women. Same results were observed for DBP and PP.”

A 2021 Israeli study of elderly hypertension subjects determined, “Cannabis treatment for three months was associated with a reduction in systolic and diastolic blood pressure, as well as heart rate.”