Higher CBD Concentrations Worsened Inflammatory Markers in Depression in Lab Tests | Research

The takeaway

In vitro testing of CBD on blood from depressed patients and controls found that while low concentrations had no immune effects, higher concentrations paradoxically increased some inflammatory markers and worsened neurotoxicity profiles.

Researchers studying CBD for depression; immunologists; clinicians considering CBD for mood disorders.

CBD 10 mcg/mL increased IL-1beta, TNF-alpha, and other pro-inflammatory markers

What the researchers found

CBD at 0.1 mcg/mL had no immune effects. CBD at 1.0 mcg/mL decreased some regulatory immune activity but increased growth factor production. CBD at 10.0 mcg/mL suppressed several immune pathways but also increased IL-1beta, TNF-alpha, and other pro-inflammatory markers. The study concluded there was no beneficial effect of CBD on depression-related immune activation.

Why it matters

CBD is widely marketed as anti-inflammatory, but this study found the opposite in the context of depression. If higher CBD concentrations can worsen inflammatory processes, this challenges the assumption that CBD is uniformly beneficial for inflammation-related depression.

The numbers in context

30 depressed patients, 20 controls. CBD 0.1 mcg/mL: no effects. CBD 1.0 mcg/mL: decreased CIRS, increased growth factors. CBD 10.0 mcg/mL: suppressed Th-1, Th-17, IRS, CIRS, neurotoxicity profile but increased IL-1beta, IL-17, TNF-alpha, GM-CSF. Dose-dependent changes in multiple cytokines.

How the study worked

In vitro study using stimulated whole blood from 30 depressed patients and 20 healthy controls. Three CBD concentrations (0.1, 1.0, 10.0 mcg/mL) were tested. Cytokine profiles were measured using LUMINEX assay, covering Th-1, Th-2, Th-17, Treg, IRS, and CIRS pathways.

What this study cannot tell us

In vitro conditions do not replicate the complexity of the human body. The CBD concentrations may not correspond to plasma levels achieved with typical oral CBD doses. The study used stimulated (not resting) immune cells, which may amplify effects.

How to read the evidence

Preliminary: in vitro study that may not reflect in vivo conditions.

When this study was published

Published in 2022.

The bigger picture

This adds nuance to the CBD narrative. The immune system in depression is already dysregulated, and CBD appears to further disrupt it in complex ways that are not simply "anti-inflammatory." This suggests CBD effects on immunity are context-dependent and dose-dependent.

Questions still open

Do these in vitro immune effects translate to clinically meaningful changes in depressed patients taking CBD? Would different CBD preparations or combinations with other cannabinoids produce different immune profiles?

Common questions

Does CBD help with depression?

This in vitro study found no beneficial effect of CBD on the inflammatory immune profile seen in depression. Higher concentrations actually increased some pro-inflammatory markers. However, in vitro results do not always predict clinical outcomes.

Is CBD really anti-inflammatory?

CBD has anti-inflammatory effects in some contexts, but this study suggests its immune effects in depression are complex and dose-dependent, with higher concentrations potentially worsening some inflammatory pathways.

Read the original research

In Vitro Effects of Cannabidiol on Activated Immune-Inflammatory Pathways in Major Depressive Patients and Healthy Controls.

Pharmaceuticals (Basel, Switzerland), 15(4)

View on PubMed ↗Publisher’s paper ↗

Citation

Rachayon, Muanpetch; Jirakran, Ketsupar; Sodsai, Pimpayao; Klinchanhom, Siriwan; Sughondhabirom, Atapol; Plaimas, Kitiporn; Suratanee, Apichat; Maes, Michael. (2022). In Vitro Effects of Cannabidiol on Activated Immune-Inflammatory Pathways in Major Depressive Patients and Healthy Controls.. Pharmaceuticals (Basel, Switzerland), 15(4). https://doi.org/10.3390/ph15040405