Could nicotine addiction have finally found a formidable opponent?

Smoking remains one of the most detrimental habits, leading to serious health issues like lung cancer, heart disease, and other critical conditions. Despite this alarming reality, over 22% of the global population still smokes tobacco, with more than 8 million fatalities attributed to it each year, according to the World Health Organization.

Approximately half of adult smokers in the U.S. attempt to quit annually; however, fewer than 10% succeed. The primary obstacles include managing strong cravings and intense withdrawal symptoms.

The U.S. Food and Drug Administration has greenlit two medications aimed at curtailing tobacco cravings: bupropion (known as Wellbutrin) and varenicline (Chantix).

Recent scientific advancements from Korea indicate that the drug procyclidine, originally designed for treating Parkinson’s disease, may alleviate physical symptoms associated with nicotine withdrawal, including tremors and reduced mobility.

“This research opens up new avenues for smoking cessation treatment by addressing the challenges presented by withdrawal symptoms,” stated Heh-In Im from the Center for Brain Disorders at the Korea Institute of Science and Technology. “It introduces an additional treatment option along with bupropion and varenicline.”

Patients with Parkinson’s disease experience an imbalance between the neurotransmitters acetylcholine and dopamine in the striatum, a crucial brain region responsible for movement control and reward processing.

The depletion of dopamine is primarily responsible for the motor symptoms that manifest in Parkinson’s patients.

Procyclidine works by blocking the activity of cholinergic interneurons, which are nerve cells that release acetylcholine. This medication alleviates muscle stiffness, tremors, and spasms experienced by patients.

In the study conducted by Im’s team, administering a low dose of procyclidine to mice showing signs of nicotine withdrawal led to over a 50% reduction in their tremors.

The underlying principle is that nicotine mimics acetylcholine, allowing it to connect to receptors on cholinergic interneurons. Their experiments revealed that inhibiting these interneurons helps to restore dopamine levels in the striatum.

Dopamine, often referred to as the “feel-good” hormone, is released in response to nicotine consumption. Those trying to quit often face cravings due to the absence of this dopamine surge. By restoring dopamine levels, withdrawal symptoms may be alleviated.

“Our future research aims to deepen the understanding of addiction mechanisms—including those related to nicotine—and to devise effective treatment strategies,” Im noted.

The findings from Im’s research were published in November in the journal Advanced Science.

With procyclidine already approved in the U.S. and other nations, the upcoming phase involves ensuring that it does not interfere with current smoking cessation therapies, while assessing if this dual approach can effectively help individuals quit smoking once and for all.