Researchers at Charité – Universitätsmedizin Berlin have demonstrated the potential for using THC, the psychoactive component in cannabis, to treat or even eliminate debilitating nightmares associated with post-traumatic stress disorder (PTSD).

The researchers behind the findings said that THC did not reduce other PTSD symptoms, such as the condition’s severity or depression. However, they plan to further explore its ability to treat nightmares, including the potential safety and efficacy associated with long-term use.

PTSD Nightmares Cause Sleep Deprivation and Fear of Going to Sleep

According to a statement from the Charité team, people who survive or witness extreme experiences such as abuse, war, disasters, or other acts of violence can become overwhelmed and unable to consciously process their experience. As a result, many experience what researchers term an “echo,” where the subconscious tries to process the trauma. The more common term for the experience is post-traumatic stress disorder, or PTSD.

People suffering from this condition often report nightmares as one of the most persistent and debilitating symptoms. Along with the horror associated with continuously reliving their traumas, sometimes on a nightly basis, sufferers also experience severe sleep deprivation. These problems are then compounded by a fear of going to sleep and experiencing nightmares repeatedly.

Attempts to treat PTSD related nightmares have found mixed results. For example, some doctors have prescribed antidepressants or blood pressure-lowering medications to treat the symptoms. However, the research team notes that pharmacological treatments are only partially effective, and “often fail to adequately relieve” PTSD-related nightmares.

There is one medication specifically approved for treating PTSD-induced nightmares. However, the team notes, it is not yet widely available, including in Germany where the study was performed. 

Exploring Alternative Treatments

To explore alternative treatment solutions, Prof. Stefan Röpke, who conducts research on trauma-related disorders at the Department of Psychiatry and Neurosciences on the Benjamin Franklin Campus of Charité, and colleagues designed experiments around tetrahydrocannabinol, or THC.

Although widely used for recreational purposes, cannabis has shown some promise for treating a wide variety of medical and psychological conditions. Still, until recently, the drug’s legal status has limited its medical applications, offering researchers a potentially untapped source of PTSD nightmare relief.

For this study, Professor Röpke and colleagues were interested in THC’s established interactions with the human body’s endocannabinoid system. That’s because this system plays a role in sleep regulation, stress, and the processing of emotional memories.

For example, the professor explained, some evidence suggests that THC reduces activity during REM sleep. Known as the dream state, REM sleep is an intense dream phase during which “the brain processes experiences and regulates emotions.

“THC reduces dream activity and thereby alleviates nocturnal stress responses,” the professor explained.

More Than a Third Report Complete Elimination of Nightmares

To start, the team enlisted more than 170 study participants. Critically, all participants suffered from PTSD and intense nightmares, resulting in sleep deprivation and a fear of going to sleep. Instead of smoking cannabis, the researchers administered a form of cannabis-derived THC drops called Dronabinol. As a legal medication, this form of THC is considered clinically safe.

During the ten-week study period, each participant was instructed to take the drops before bedtime. Half of the participants received THC drops, while the others received cannabis-flavored placebo drops. To maintain double-blind study integrity, neither the participants nor the researchers knew who received which treatment.

After the trial period finished, the researchers discovered several positive results. Most notably, the THC group reported a significant decrease in nightmares compared to the placebo group.

According to the study authors, when ranking a participant’s “nightmare burden” on a scale of zero to eight points, participants’ scores dropped by an average of 3.7 points. For comparison, the placebo group experienced an average drop of 2.2 points.

Perhaps even more significant, Professor Röpke said that “more than a third” of the THC patients reported a complete absence of nightmares after the ten-week period concluded. The professor also noted that 21 percent of the study participants reported that their nightmare burden had been at least cut in half. Finally, the professor said that five out of six study participants in the THC group “felt their health had markedly improved.”

Exploring the Safety and Efficacy of Long-Term THC Use

Although the study results offer some possible hope for relief from nightmares and improved sleep, the researchers said the THC treatments did not affect all PTSD symptoms. For example, they observed that a participant’s PTSD severity and any accompanying depression “did not change conclusively.”

No severe side effects were reported by the THC group. However, the researchers did observe some minor complaints, such as headaches, dizziness, or increased appetite. Participants did not report any withdrawal symptoms after the cessation of the treatment period.

Moving forward, the team will explore the safety and effectiveness of long-term nightly THC treatments. They also hope to explore whether patients develop a tolerance to THC’s nightmare-abating effects over time.

The study “Dronabinol for nightmares in post-traumatic stress disorder: a randomized controlled trial” was published in Nature Medicine.

Christopher Plain is a Science Fiction and Fantasy novelist and has spent the last six years as Associate News Editor and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him at christopher@thedebrief.org

For patients with disorders of consciousness such as coma, vegetative states, or unresponsive wakefulness, clinicians face a longstanding challenge of determining whether any awareness remains. While surface brain recordings can measure general electrical activity, they do not reveal what is happening deep within the brain.

Now, a new study from Ludwig-Maximilians-Universität München may bring clinicians closer to a measurable indicator of brain states in these conditions.

Researchers at LMU have found a new type of electrical rhythm in the central thalamus, a small area deep inside the brain. Published in Nature Human Behaviour, the study suggests that this rhythm could serve as a biological indicator of conscious states.

A Signal That Tracks Awareness

The signal does more than just appear with consciousness. It also changes as the brain moves between different states. For example, the rhythm becomes stronger during REM sleep, which lets researchers see small shifts in awareness even within the same stage of sleep.

“Our results show that the central thalamus plays an important role in regulating brain states,” said Dr. Aditya Chowdhury, lead author of the study. “In the context of existing research, our results show that this small deep-lying brain structure could actively influence our states of consciousness.”

Professor Tobias Staudigl, who led the research team, argues the signal’s consistency makes it more than just an interesting discovery. “These characteristic rhythm patterns can be reliably attributed to specific states and thus have the potential to serve as a measurable biological signature of states of consciousness,” Staudigl said.

Getting Inside the Deepest Part of the Brain

Recording electrical activity from deep brain structures is one of neuroscience’s most persistent technical problems. Standard surface EEG can detect general patterns from the brain’s outer layers, but it misses details from deeper areas. Since the thalamus sits at the center of the brain, it has remained largely inaccessible through non-invasive methods.

The LMU team had a rare chance to study this. Their research involved patients already undergoing deep-brain stimulation therapy for epilepsy, which uses electrodes in the thalamus to help control seizures. These electrodes let the researchers record signals directly from inside the thalamus, something that is almost never possible otherwise.

The team combined these recordings with surface EEG, eye-tracking, and detailed sleep-stage analysis. This approach allowed them to see how thalamic activity changes as patients transition between wakefulness and different sleep stages. Their findings offer the most detailed picture yet of what the thalamus actually does as consciousness changes.

Medical Implications

Disorders of consciousness, like coma, vegetative state, and minimally conscious state, are some of the hardest problems in neurology. One reason is that doctors have lacked reliable biological markers to assess patients’ awareness. The thalamic rhythm found in this study could help solve that problem.

If this signal truly tracks brain states linked to consciousness, it could help doctors evaluate awareness in patients who cannot communicate, guide treatment choices, and monitor how patients respond to care over time. The researchers believe it could also be used to improve deep brain stimulation therapy by allowing doctors to adjust treatment based on real-time thalamic activity rather than general clinical signs.

Staudigl was recently awarded funding by the European Research Council to explore the clinical potential of this discovery and to develop applications for treating neurological disease.

Understanding consciousness has always been one of science’s most difficult challenges. While the study does not answer the fundamental question of what consciousness is, these findings provide a consistent, measurable signal that indicates how the brain moves between conscious and unconscious states.

Austin Burgess is a writer and researcher with a background in sales, marketing, and data analytics. He holds an MBA, a Bachelor of Science in Business Administration, and a data analytics certification. His work focuses on breaking scientific developments, with an emphasis on emerging biology, cognitive neuroscience, and archaeological discoveries.