Nicotine

Nicotine
The skeletal formula of nicotine
Chemical Nomenclature
Common names	Nicotine
Systematic name	(S)-3-[1-Methylpyrrolidin-2-yl]pyridine
Routes of Administration
Smoked Dosage WARNING: Always start with lower doses due to differences between individual body weight, tolerance, metabolism, and personal sensitivity. See responsible use section. DISCLAIMER: PW's dosage information is a summary of data gathered from users and resources. It is not a recommendation and should be verified with other sources for accuracy. Threshold 0.5 mg Light 0.5 - 1 mg Common 1 - 2 mg Strong 2 - 4 mg Heavy > 5 mg Duration Total 1 - 2 hours Onset 5 - 60 seconds

Summary sheet: Nicotine

Nicotine is a potent naturally occurring alkaloid found in the nightshade family of plants (Solanaceae) and a stimulant drug. It is most commonly found within tobacco.

Chemistry

Nicotine, or (S)-3-[1-Methylpyrrolidin-2-yl]pyridine, is a synthetic bicyclic compound comprised of a pyrrolidine ring attached to the second carbon of a pyridine ring. Pyridine is a six-membered ring structurally related to benzene with a nitrogen member. Nicotine additionally contains an N-substituted (R₁) pyrrolidine ring. These rings are bridged from R₃ of the pyridine ring to R₂ of the pyrrolidine ring. Both optical enantiomers of nicotine are active, with the naturally occurring levorotatory enantiomer being more active and more toxic than the dextrorotatory. In its basic form, it is an oily liquid that is miscible with water. However, as a nitrogenous base nicotine readily forms solid, water soluble salts when acidified.

Pharmacology

Nicotine produces its stimulating effects by agonising nicotinic acetylcholine receptors, causing the liver to release glucose and the adrenal medulla to release epinephrine (adrenaline).

Once it reaches the brain, nicotine stimulates the release of many neurotransmitters and hormones including acetylcholine, norepinephrine, epinephrine, arginine vasopressin, serotonin, dopamine, and beta-endorphin, which are responsible for the majority of its psychoactive effects.

By increasing the level of acetylcholine in the brain, nicotine enhances concentration. Norepinephrine release causes enhanced alertness and arousal. With low doses, nicotine enhances the action of norepinephrine and dopamine, which produces typical psychostimulation. Nicotine also has sedative effects as produced by the release of beta-endorphin (which reduces anxiety) and enhances the action of serotonin and opioids (which causes sedation).

Bioavailability

• Oral: 20% - 45%
• Intranasal: 53%
• Transdermal: 68%

Metabolism

Nicotine has a half-life of 1 - 2 hours when administered in a single dose and an active metabolite (cotinine) with a half-life of 20 hours.

Subjective effects

The effects listed below are based upon the subjective effects index and personal experiences of PsychonautWiki contributors. The listed effects will rarely (if ever) occur all at once, but heavier dosages will increase the chances and are more likely to induce a full range of effects.

Physical effects

• Stimulation and Sedation - The stimulatory effects of nicotine are much less pronounced than other stimulants such as caffeine or amphetamine. At higher doses, however, nicotine inhibits nerve transmission which produces sedative effects.
• Abnormal heartbeat - At high doses, nicotine can trigger an elevated heart rate or even heart palpitations.
• Vasoconstriction
• Appetite suppression
• Dizziness - At high doses, nicotine can cause one to feel dizzy or lightheaded.

Cognitive effects

• Thought acceleration
• Focus enhancement
• Memory enhancement
• Motivation enhancement
• Euphoria
• Anxiety and Anxiety suppression - Low doses of nicotine produce stimulatory effects which can cause anxiety. Higher doses stimulate the release of beta-endorphin which relieves anxiety.
• Sexual arousal - Nicotine has the capability of inducing heightened sexual arousal due to its effect on dopamine transmission.
• Compulsive redosing

Forms

generic smoking tobacco

Tobacco

The most common source of nicotine is Nicotiana Tabacum, constituting 0.6% - 3.0% of its dry weight. It is also present in other species of Nightshade (Solanaceae) such as Indian Tobacco (Nicotiana Rustica).

Nicotine Replacement Therapy

Nicotine is also available in several forms which can be administered without smoking. Popular products include sublingual lozenges and sprays, dermal patches, inhalers, and solutions used for oral use or in conjunction with a vaporiser.

Toxicity and harm potential

Radar plot showing relative physical harm, social harm, and dependence of nicotine in the form tobacco

It is strongly recommended that one use harm reduction practices when using this drug.

Lethal dosage

Nicotine has an estimated oral LD50 of 6.5 - 13 mg/kg in humans, which is much lower than many other common stimulants. It is unlikely that overdose can be achieved by smoking tobacco, however, coadministration with other sources of nicotine such as patches or gum may potentially be dangerous.

Nicotine readily passes through the dermis and into the bloodstream upon contact with skin, so safety precautions should be taken when handling it in its pure form.

Tolerance and addiction potential

Nicotine activates the reward system (mesolimbic pathway) of the brain, which is responsible for its addictive nature. Because of this, tobacco smoking is as addictive as cocaine or heroin, which both have similar mechanisms of addiction.

Chronic use of nicotine, as with many other addictive drugs, downregulates the production of dopamine and other stimulatory neurotransmitters and also desensitises nicotinic acetylcholine receptors. In response, the brain upregulates the number of receptors presented. The net effect is an increase in sensitivity to the reward system; the opposite of the decrease in sensitivity as caused by addictive drugs like cocaine and heroin.

Following discontinuation of nicotine, receptors may take several months to return to baseline.

Pregnancy

Nicotine has been indicated in the increased frequency of birth defects, and has been correlated with the increase of attention deficit hyperactive disorder in children.

Legal issues

Nicotine is legal all over the world and as such is one of the most popularly used drugs. The sale of tobacco products are usually restricted to adults, and they are often heavily taxed.

See also

• Responsible use
• Stimulants
• Nicotine (Wikipedia)
• Nicotine (Erowid)