Thursday, September 20, 2012

An Absorbing Nicotine Lesson

Nicotine uptake from snus, cigarettes and medicinal gum varies significantly, new research shows.

Helena Digard of British American Tobacco is lead author on the work, joined by colleagues from her company and from Sweden’s Lund University; their research was published in Nicotine and Tobacco Research (abstract here).

Dr. Digard provided 20 Swedish dual users of snus and cigarettes with two loose and two pouched snus products with different nicotine levels; nicotine gum; and a cigarette, over the course of six sessions.  Snus was placed in the upper lip for one hour only and not moved; the cigarette was smoked ad lib for 5 minutes or until reaching a prescribed length; the gum was chewed every 2 seconds for 30 minutes, with juices swallowed once every minute. 

The chart from the journal illustrates critical nicotine absorption data:

1.  Cigarettes produced a rapid, but transient, nicotine spike.  Peak blood nicotine levels of around 12 nanograms (ng) per milliliter (ml) were seen seven minutes after starting to smoke, followed by a steep decline.

2.  Snus produced similar nicotine levels much more slowly, but they stayed higher longer.  The products produced varying nicotine levels (~ 10-17 ng/ml) that correlated with their nicotine concentrations; the peak occurred one hour after placement.  Subsequent declines were also slower; after two hours, nicotine levels ranged from 7 to 12 ng/ml.

3.  Nicotine gum produced low blood nicotine levels much more slowly.  The peak (8 ng/ml) at 45 minutes was similar to the cigarette level that had declined by one-third. 

These findings are similar to those reported 24 years ago in the New England Journal of Medicine (reference here); they are particularly relevant for cigarette smokers making the switch to smoke-free nicotine products. 

The big lesson: Snus delivers satisfying doses of nicotine, but not as quickly as cigarettes.  However, slower nicotine delivery means slower decline – a distinct advantage.  Switchers generally use fewer pinches or pouches of smokeless tobacco compared to the number of cigarettes they smoked, as documented in my published research in the U.S. (here and here) and in Sweden (here). 

When unit consumption drops, smokers save money, further incentivizing them to stick with their switch to safer smokeless products.


Jonathan Bagley said...

Well that explains why nicotine gum is useless both as an aid to quitting and a way of getting through plane journeys and long meetings. The peek nicotine level is about the same as that 50 minutes after a cigarette, just the time you are thinking about having another. Is this intentional? It's probably the most profitable way of selling the gum. Pouched snus, which I sometimes use (I don't know now whether shipments have been stopped - after the complaints of a Finnish cancer charity. Oh, the cruel irony), is way above that level after 120 minutes. I've got off a plane and forgotten about having a cigarette. The European Commission should be charged with crimes against humanity.

Phönix said...

Well, this repeats the old "spikes theorie" which is more than useless to explain nicotine addiction. Nicotine alone is not addictive, neither in NRTs nor e-cigarettes.
And something else is wrong. Any user of nicotine enjoys nicotine to his/her individual pleasure level. Then there is enough nicotine available to occupy any free space on acetylcholine receptors. It is a steady state. Some nicotine molecules more or less won`t make a difference. And I would really like to see this study repeated ... starting from the steady state.