What Does the Evidence Show on Cannabidiol for Anxiety?

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Anxiety disorders are among the most common psychiatric conditions and can significantly affect quality of life. Although anxiety is a normal stress response, anxiety disorders involve excessive or persistent fear and worry that interfere with everyday life.

Symptoms vary depending on the type of anxiety disorder, but may include:

• Excessive or persistent worry
• Fear or apprehension
• Increased heart rate
• Rapid breathing
• Sweating
• Fatigue
• Difficulty concentrating
• Sleep disturbances

Because conventional treatments do not work equally well for everyone, researchers have been investigating whether cannabidiol (CBD), a non-intoxicating compound found in cannabis, could have a role in treating anxiety.

How does cannabidiol affect anxiety?

CBD does not produce the "high" associated with tetrahydrocannabinol (THC), another major cannabis compound. Laboratory and human studies suggest that CBD can affect several systems involved in anxiety and stress, including serotonin signaling and the endocannabinoid system.

However, the exact mechanisms behind its potential anxiolytic effects are still being investigated. More importantly, evidence from laboratory studies cannot automatically be translated into an effective treatment for anxiety disorders in humans.

What do recent studies show?

Research published since 2020 has provided some encouraging results, but it has also made the limitations of the evidence clearer.

A 2024 systematic review of randomized controlled trials identified 11 eligible studies. The researchers found that the results were inconsistent, partly because the studies differed considerably in the anxiety disorders studied, CBD doses, treatment duration, and methods used to measure anxiety. The authors concluded that CBD may reduce anxiety, but better-designed clinical trials are still needed.

Another systematic review and meta-analysis, also published in 2024, analyzed eight studies involving 316 participants. It found a significant reduction in anxiety among people receiving CBD compared with control groups. However, the authors emphasized that the small number of participants and limitations of the available studies make the findings difficult to interpret with confidence.

One of the more notable recent studies was a 15-week randomized, double-blind, placebo-controlled trial involving 178 people with mild to moderate anxiety disorders. Participants receiving a specific nanodispersible CBD formulation showed greater improvements in anxiety scores than those receiving placebo. The study reported no serious adverse events.

This result is encouraging, but it should be interpreted cautiously. Several authors of the study were employees or executives of companies involved in developing the CBD formulation, which represents a potential source of bias.

Other recent trials have produced less encouraging results. For example, a randomized placebo-controlled study of people with high levels of worry found that a single dose of CBD did not reduce anxiety or worry. After two weeks of treatment, 300 mg of CBD reduced some measures of anxiety but did not reduce worry, one of the central cognitive symptoms of anxiety.

Similarly, a 2024 randomized trial involving people exposed to trauma found that 300 mg of CBD did not significantly reduce anxiety, distress, or heart rate in response to trauma-related reminders.

Taken together, these findings suggest that CBD may have anxiolytic effects in some circumstances, but the evidence does not yet establish it as a reliable treatment for anxiety disorders.

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Is CBD safe?

CBD is often described as harmless because it does not produce the intoxication associated with THC, but that does not mean it is free of risks. CBD can cause adverse effects and may interact with other medications. The U.S. Food and Drug Administration has also warned about the potential for liver injury and drug interactions. These concerns are particularly important for people taking medications regularly.

The quality and composition of commercially available CBD products can also vary. For example, a product labeled as CBD may contain different amounts of CBD than stated on the label and may contain other cannabinoids, including THC.

For these reasons, people taking medication should discuss CBD use with a healthcare professional rather than assuming that it is automatically safe because it is derived from a plant.

Can CBD treat anxiety?

The answer is not yet clear.

Research has moved beyond the small case series and early studies available in 2020, and some newer clinical trials and meta-analyses suggest that CBD may reduce anxiety. At the same time, other well-controlled studies have found little or no benefit.

The most accurate conclusion at this point is that CBD is a promising but unproven treatment for anxiety disorders. Larger, independent clinical trials are still needed to determine which patients might benefit, what doses are appropriate, how long treatment should continue, and how CBD compares with established treatments.

CBD should therefore not be considered a replacement for evidence-based treatments for anxiety until stronger evidence is available.