Scientists now know the reason why people who are actively trying to stop smoking often itch uncontrollably.
Belgian researchers, who studied the effect of nicotine in mice, found that it activates a molecular pathway in membranes in the skin, nose and mouth known to play a role in inflammation.
The study, published in the journal Nature Neuroscience, could help develop smoking cessation aids with fewer side effects, reports The BBC.
Nicotine Replacement Therapy (NRT) gives the body nicotine without the harmful effects of smoking or chewing tobacco, and the purpose behind it is to gradually reduce the addiction by using a low nicotine dose to take the edge off the cravings.
Generally, individuals who use nicotine patches or gum double their chances of successfully quitting. But some do experience side effects with NRT. Nicotine patches commonly cause skin irritation, and nicotine inhalers and nasal sprays may cause irritation in the mouth or nose.
Now, in the latest study, Karel Talavera of the Leuven Catholic University in Belgium found that in mice, nicotine directly activates TRPA1, a pathway or channel in cells known to convey information about irritating substances and inflammatory pain. They also found that mice lacking TRPA1 showed no irritation when nicotine was put into their noses.
Writing in Nature Neuroscience, researchers said: "Our results indicate that inhibition of TRPA1 represents an interesting approach for developing smoking cessation therapies with less adverse effects."