Cocaine is only second to methamphetamine as causing the greatest psychological addiction. The drug stimulates release and accumulation of dopamine, a neurotransmitter linked to pleasure in the brain’s reward circuit. Flooded with dopamine, users describe highly addictive euphoric sensations that make it nearly impossible to quit.
The research is based on previous animal studies that showed compulsive cocaine cravings weaken the frontal cortex of the brain. In addition, when this area of the brain was optogenetically stimulated in animals, cocaine cravings declined. The researchers are the first to test whether this would work in cocaine-addicted human patients."Despite the fact that more than 20 million people worldwide suffer from cocaine use disorders, there are no effective neurobiological treatments for patients with this devastating condition.” – Dr. Antonello Bonci, co-author of the study.
The research team enrolled 32 cocaine-addicted patients and randomly assigned them to be in the experimental or the control group. Experimental patients received magnetic treatment known as repetitive transcranial magnetic stimulation (rTMS). The treatment was targeted to the prefrontal cortex, an area known to be involved in decision making. Control patients received standard medication to relieve symptoms of addiction instead of rTMS.
Over 29 days (Stage 1), patients in the experimental group received a total of rTMS treatments. Researchers reported the rTMS patients in this stage had a higher number of cocaine-free urine drug tests, compared to the control group. rTMS patients also reported lower cocaine cravings than the control patients.
The researchers then performed a 63-day follow-up (Stage 2), during which they offered rTMS treatment to all of the patients, to include those initially in the control group. These patients showed similar results to those of the rTMS group, in reduced cravings and drug-free urine tests."rTMS is a non-invasive and very safe therapeutic approach which is used with other mental health and neurological conditions, such as depression and neuropathic pain. Our study suggests that rTMS may also represent a new treatment for patients with cocaine use disorder.” – Dr. Antonello Bonci
The results of this study are promising, but highly preliminary. For one thing, the sample size is exceedingly small, making it difficult to generalize the positive response of rTMS therapy. In addition, the results of the trial would be strengthened with placebo rTMS treatment as the control. This would allow more accurate conclusions of whether rTMS treatment actually reduced cocaine cravings. And finally, it would be vital to understand if the improvement in cocaine cravings can be sustained over a significant amount of time. After all, how effective is a therapy if the results are only temporary?
But for now, this is the first clinical trial to suggest that magnetic stimulation has the potential to reduce cocaine cravings. Though unconventional and preliminary, magnetic stimulation represents a new approach to a notoriously addictive condition.
Sources: European Neuropsychopharmacology, Eurekalert