This New CBD Formula Actually Reaches the Brain

CBD (cannabidiol) is everywhere, but how much actually reaches the brain when you take it?

A research team at the University of Rochester and Harvard Medical School has developed a novel nano-micelle formulation of CBD that reached high brain concentrations and relieved neuropathic pain in mice within 30 minutes.

Their results suggest that improving the delivery of CBD into the nervous system may unlock its therapeutic potential for chronic pain.

Why CBD hasn’t delivered for chronic pain yet

CBD, a non-psychoactive compound from cannabis, has become widely marketed for pain relief. Yet despite its popularity, CBD’s actual effects on the nervous system remain poorly understood.

Currently, the only Food and Drug Administration-approved CBD product is for specific forms of epilepsy. Its efficacy for chronic or neuropathic pain is inconsistent and often unclear. Prior animal studies have shown mixed results; while CBD can prevent pain onset in some models, it has largely failed to reverse established neuropathic pain.

A key barrier is its poor water solubility and low capacity to cross the blood–brain barrier, which limits delivery of CBD to the brain and spinal cord.

“We need to understand more about this compound, what mechanisms it interacts with in the brain, its impact on the body and whether it is a potentially safer solution for treating the chronic pain epidemic,” said corresponding author Dr. Kuan Hong Wang, a professor at the University of Rochester Medical Center.

Chronic neuropathic pain is particularly difficult to treat, and current options such as gabapentin or opioids often have significant side effects and may only deliver partial relief.

Wang and the team aimed to develop a formulation that delivers CBD effectively to the brain and investigate its effects on pain‐related pathways.

How the new CBD-IN nano delivery system works

To solve the problem of poor brain delivery, the researchers created a new formulation called CBD-IN, which suspends CBD inside tiny water-friendly spheres. These nano-micelles are small enough to move efficiently through the bloodstream and cross the blood–brain barrier.

When tested in mice with spared nerve injury, a widely used model for neuropathic pain, a single dose of CBD-IN, delivered either by injection or by mouth, produced measurable pain relief within 30 minutes.

The treated mice regained normal touch sensitivity and showed no loss of coordination, balance or memory.

Mass-spectrometry analysis confirmed that CBD-IN delivered significantly higher CBD concentrations to the brain than the standard oil-based or single-solvent formulations.

It also cleared from the liver more quickly, which could reduce the risk of liver toxicity seen with some CBD products.

“The pain relief also lasted through repeated use,” said first author Dr. Jingyu Feng, staff scientist in Wang’s lab at the University of Rochester Medical Center. “We did not see its effect wear off over time.”

Behavioral testing showed that CBD-IN reduced pain from light touch and lowered exaggerated response to painful stimuli, while sparing normal sensory and motor function – an advantage over gabapentin and opioids, which often dull movement and cognition.

Further experiments using genetic activity mapping and calcium imaging revealed that CBD-IN calmed overactive neurons in pain-processing regions, including the spinal cord, the thalamus and the somatosensory cortex, without altering activity in healthy circuits.

Pain relief also did not rely on the classical CB1 or CB2 cannabinoid receptors, pointing to a novel mechanism of action.

“Instead, CBD-IN seems to influence broader electrical and calcium signaling in nerve cells, offering a new way to control nerve hyperactivity without triggering the ‘high’ or dependency risks associated with traditional cannabinoids or opioids,” Feng said.

What this means for pain treatment

By improving its bioavailability and allowing it to act only where nerve circuits are overactive, the findings suggest a higher degree of selectivity than many existing pain treatments.

“The broader implication of this research is that nanotechnology can make natural compounds like CBD more effective and precise,” said Wang.

“By enhancing brain delivery and targeting only disease-related neural overactivity, this strategy could open new doors for treating chronic pain and possibly other neurological disorders, such as epilepsy or neurodegenerative diseases, where abnormal nerve activity plays a central role,” he added.

A targeted, fast-acting mechanism could make cannabinoid-based therapies safer and more reliable. However, several questions remain. The precise molecular targets of CBD-IN are still uncertain, and the study only involved mice. Human trials will be needed to confirm safety, optimal dosing and long-term effects.

By addressing the long-standing delivery barrier that has limited CBD’s medical use, this study provides a clear framework for using nanotechnology to refine natural therapeutics for neurological disorders.

 

Reference: Feng J, Page J, Chung L, He Z, Wang KH. Rapid suppression of neuropathic pain and somatosensory hyperactivity by nano-formulated cannabidiol. Cell Chem Biol. 2025:S2451945625003423. doi: 10.1016/j.chembiol.2025.10.005

This article is a rework of a press release issued by the University of Rochester Medical Center. Material has been edited for length and content.