˚₊‧ʚ♡ɞ‧₊˚ nicotine/tobacco ˚₊‧ʚ♡ɞ‧₊˚ Flashcards
How is tobacco used/administered?
Smoked as cigarettes, cigars, pipes. Smokeless forms can be snorted into nostrils, chewed, or absorbed across gums. all tobacco contains nicotine.
what’s in tobacco besides nicotine?
More than 4,000 substances with 2 phases: gaseous (carbon monoxide, ammonia, cyanide, acetone) & particulate phase (tar).
what is nicotine? Is it a widely used drug?
Nicotine is a poisonous & highly addictive alkaloid stimulant, a key ingredient in insecticides, and one of the most toxic of all drugs.
It’s one of the most widely used drugs in the world.
Pharmacokinetics (ADME) for nicotine?
A: mucus membranes, skin, inhalation.
D: readily throughout the body.
M: metabolized by liver CYP216 & lungs.
E: by kidneys in urine; half-life of 2hrs. Quick half-life leads to quick withdrawal (frequent use throughout the day)
What factors can slow (inhibit) nicotine’s metabolism?
Foods & drugs (menthol, grapefruit juice, SSRIs, smoking; genetics (low levels of enzymes that break down nicotine tend to smoke fewer cigs) age (elderly + newborns metabolize nicotine slower)
what factors can speed up (enhance) nicotine’s metabolism?
Gender (women metabolize faster–especially when pregnant tor taking oral contraceptives), race (black men have higher levels of nicotine metabolites)
What are the active metabolites?
Cotinine and Nicotine-1-N-Oxide.
What receptors/neurotransmitters does nicotine interact with?
Acetylcholine receptor; agonist binding to nicotinic acetylcholine receptor
Describe the biphasic effect
Binds to nicotinic cholinergic receptors & excites them; then stays bound (even after activitys done) – when it stays bound, becomes an antagonist, blocking NTs at that receptor.
Where in the nervous system does nicotine act?
CNS: cortex, hippocampus, nucleus accumbens, VTA.
PNS: somatic NS neuromuscular junctions & autonomic NS increases sympathetic NS activity.
What are the acute behavioral symptoms?
Bc nicotinic acetylcholine receptors are involved in the sympathetic NS fight or flight response; you get the release of adrenaline/epinephrine from the adrenal glans, which leads to stimulant-like effects & anxiety.
Does tolerance develop?
Short-term tolerance progresses as the day develops (bc short half-life). Later cigs have less effect. Smoking increases the metabolism of nicotine throughout the day (metabolic tolerance).
What factors make nicotine so addictive?
It stimulates dopamine’s release from nucleus accumbens, addiction center of brain. Nic is frequently and quickly reenforcing. It’s quickly metabolized and cleared, meaning “high” (effects” don’t last long. Withdrawal onset occurs rapidly, tobacco users often seek out drug to ease withdrawal symptoms.
Cravings are impacted by availability of drug and self-control. Smokers experience more craving when cigs are immediately available. Smoking becomes conditioned habit associated w rewarding behavior—after meal, while drinking, socializing, after sex. Smokers associate settings and circumstances w smoking, leading to learned rewards. Many rituals associated w smoking, which strengthens habit. Tobacco is legal and readily available. Smokers often gather to share their drug. It’s portable, easy to store, and needs no equipment other than lighter or match.
What are some withdrawal symptoms?
Headache, trouble concentrating, irritable, tired.
What are the treatments for nicotine addiction?
Pharmacological treatments: Bupropion & Chantix.
Behavioral & psychosocial treatments: counseling, stress management, behavior modification, hypnosis.
