Nicotine: Ingestion methods
Last modified: Saturday, 20. June 2009 - 1:14 pm
Nicotine is ingested by smoking shredded tobacco in cigarettes, cigars, and pipes, or through smokeless tobacco. Smokeless tobacco comes in two major forms: snuff and chewing tobacco. Snuff is cured, ground tobacco manufactured in three varieties: dry, moist, and fine cut. Chewing tobacco is coarser than snuff and is also produced in three forms: loose-leaf, plug, and twist.
Today, moist snuff is usually taken orally, similar to chewing tobacco. Usually a pinch of snuff or a plug of chewing tobacco is placed between the gum and cheek, or the leaves or plug are chewed. Saliva mixes with the tobacco, and nicotine is absorbed through the lining of the mouth. This moist tobacco is referred to as a “chaw” or “quid” of chewing tobacco or a “dip” or “pinch” of snuff. It may be kept in the mouth for hours, and the user expectorates (spits out) the saliva that mixes with the tobacco. Dry snuff, which is less commonly used, is usually inhaled through the nose.
Absorption and metabolism
Nicotine is easily absorbed through all body surfaces including the lungs, oral and nasal passages, skin, and gastrointestinal tract. Absorption is influenced by the pH (acidity) of the smoke or chew. Cigarette smoke is acidic, and therefore the nicotine is best absorbed through the alveoli (tiny air sacs) of the lungs during deep inhalation. Cigar and pipe smokers typically do not inhale the alkaline smoke, and nicotine absorption, like that of smokeless tobacco, occurs through the lining of the mouth. Inhalation provides the quickest route of nicotine delivery to the brain and is therefore the most addictive. Absorption through the mouth is slower and through the skin slower yet.
Nicotine in chewing tobacco is absorbed in the first 10 minutes, with peak levels occurring within 30 minutes. The nicotine from a puff of cigarette reaches the brain within 10 seconds. With approximately 10 puffs per cigarette, a pack per day delivers 200 doses (hits) of this potent drug to the brain. The repeated, frequent peaks in nicotine levels in the brain and blood contribute to its addictiveness.
The smoke is 1% to 2% nicotine and approximately 1-3 mg of the drug reaches the smoker’s bloodstream per cigarette. Half of the nicotine is eliminated from the blood in 30 to 120 minutes. This short half-life is the result of a portion of nicotine in the blood being metabolized (broken down or changed into other substances) in the liver, lungs, and other organs. Primarily, it is oxidized into cotinine, a less active substance. The kidney then rapidly removes nicotine and cotinine from the body.
The short half-life of nicotine contributes to its abuse potential. The initial effects drop off after a few minutes, causing the user to continue self-administering nicotine throughout the day to maintain pleasurable effects and prevent withdrawal symptoms. Studies clearly show that animals will self-administer nicotine intermittently to avoid both very low and very high levels of nicotine.
Incoming search terms:
- ways to ingest nicotine
- ways to consume nicotine