What is Nicotine?
Nicotine, an alkaloid found in the leaves of tobacco plant, is an exceptionally addictive substance and is the active component of tobacco smoke. Tobacco leaves contain around two to seven percent nicotine. This substance imitates the effects of the neurotransmitter acetylcholine and largely affects the autonomic nervous system. It can cause paralysis and respiratory failure even at doses below 50 mg.
Biosynthesis of nicotine occurs in the roots and carried to the leaves for storage to help protect the plant from insects. Five percent of tobacco plant’s dry weight is nicotine and depending on the cigarette brand, one stick may have eight to twenty milligrams of nicotine. An individual smoking a cigarette can inhale roughly 3mg of nicotine but only about one milligram is actually absorbed by the body. At this dose, nicotine can already affect the central nervous system and can cause constriction of blood vessels, tachycardia, tachypnea, hyperglycemia or nausea.
In the United States, nicotine is considered to be among the greatly used addictive drug. According to the National Household Survey on Drug Abuse, approximately 62 million individuals from age twelve and up are cigarette smokers – that’s roughly 29% of the US population. Worldwide, around one-third of the adult male population smokes. Everyday around 80,000 to 100,000 children would start smoking and almost half of them are from Asia.
How long does nicotine stay in your system?
Once nicotine is inhaled, it is quickly absorbed into the system due to the high blood flow in the lungs. It would only take around ten seconds for it to reach the brain. Nicotine is principally metabolized in the liver but breakdown can also occur in the lungs and kidneys. The main metabolites produced are nicotine N-oxide and cotinine (major indicator of nicotine presence). Generally, it would take about 72 hours from last use for other nicotine by-products to leave the system but cotinine would remain in the system for as long as four days. But it could also remain for several months, depending on how much tobacco was smoked and the length of time the user has actually smoked.
How long does nicotine stay in your blood?
The length of time nicotine remains in the blood stream would depend on the amount consumed and the frequency of consumption. Nicotine can stay for 48 hours and beyond this time it will not be detected either in the blood or urine. However, the cotinine metabolite can generally leave traces for about 7 days. There are some individuals who have anomalies in their genes that trigger the slow metabolism of cotinine. They would need to stop smoking for at least a day or more to clear the nicotine metabolites from their system. Cotinine levels should be less than 10ng/ml for one to pass the blood tests.
How long does nicotine stay in your urine?
The length of time it would take for nicotine and its metabolites to stay depend on the user’s rate of metabolism, height, weight and the how much water is consumed in a day. On average, nicotine can be detected in the urine for as long as three days. Passive smokers have nicotine traces for about fifteen to twenty days.
How long does nicotine stay in your saliva?
A large amount of nicotine will be excreted from the system within twenty minutes after smoking but will be detected in the saliva for approximately 24 hours after the last smoke. Its metabolite, cotinine, would be detected for as long as 4 to 7 days depending on the amount of nicotine consumed. For heavy smokers, it can be detected up to seven to fourteen days.
Nicotine Effects
Once nicotine is absorbed, it will stimulate the adrenal glands causing it to release epinephrine or adrenaline. The sudden increase of this hormone would promote glycogenolysis as well as tachycardia, tachypnea and blood pressure increase. Moreover, nicotine inhibits insulin release causing slight hyperglycemia and appetite suppression. Nicotine can act as a stimulant and enhance the activity of the brain, improving concentration, memory and cognitive processes. Dopamine release is enhanced causing pleasurable sensations and a calming effect in most smokers. But unlike other drugs or substances, nicotine has a dual effect on the body – it can act as a stimulant or a sedative- depending mainly on how it is taken. A stimulating effect is achieved if the smoker draws in short, brisk puffs which would produce low blood levels of nicotine and stimulating the release of dopamine and norepinephrine. On the other hand, deep puffs increase the level of nicotine in the blood thus reducing the transfer of nerve impulses causing a sedative and calming effect due to the release of serotonin.
Studies have shown that women are more prone to develop cancer if they smoke. Moreover, women smokers would experience early menopause compared to those who don’t smoke. If these women also are taking oral contraceptives, chances of developing cerebrovascular and cardiovascular diseases are increased.
Nicotine Addiction
Regardless of the risk linked with cigarette smoking, people all over the world are still continuing to smoke. Many are attempting to quit but most of them are unsuccessful. Nicotine is basically as addictive as cocaine or heroin.
Nicotine has neurophysiologic action on the reward center of the brain or the mesolimbic dopamine system, particularly at the nucleus accumbens (dopamine-rich section). Dopamine release from this section would promote and reinforce pleasure. Aside from dopamine, endorphins and corticosteroids are also released which would reduce fatigue and increase information and cognitive processing – causing the desire to repeat the experience over and over again thus leading to addiction.
Addiction to nicotine is basically physical dependence. When a smoker stops smoking, “nicotine craving” is brought about. Individuals react in different ways when nicotine is withdrawn from the system, it may be severe. This is the reason why most smokers have a hard time quitting.
Nicotine Drug Test
Urinal Drug Test
There are available economical test strips that would detect cotinine in the urine through immunoassay. These inexpensive strips are not that sensitive and could only detect 200ng/ml cotinine levels within two to five days. More precise urine tests are available through GC-MS that can detect cotinine levels of 5ng/ml or “Ion Pair Reversed-Phase Chromatography” that has a detection cut-off of 200ng/ml. Both tests have longer detection time – seven to ten days- but are more costly and would take a longer time to get the results.
Nicotine Hair Test
Hair tests can detect both nicotine and its metabolite, cotinine, through GC-MS. The detection cut-off for this procedure is approximately 2ng/ml nicotine. The test will determine the amount of drug molecules that were permanently trapped inside the follicles. The standard test can cover at least 90 days from last nicotine use.
Blood Test for Nicotine
Nicotine presence can be detected in the blood for a short period only (about 48 hours) but its metabolite, cotinine, can be detected up to about three weeks from last use and the cut-off detection levels is 200ng/ml. The amount of nicotine and the length of nicotine use will affect the detection time of nicotine in the bloodstream.
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