Transcript Psychoactive Plants

Psychoactive Plants
Stimulants - I: Cocaine
Psychoactive Plants
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Psychoactive plants act on the central nervous
system - often by influencing neurotransmitters or
endorphins
Can be divided into three categories
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Stimulants – excite or enhance psychomotor activity
(caffeine, cocaine)
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Depressants – reduce mental and physical performance
(opiates, alcohol, kava)
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Hallucinogens – induce a dreamlike state and
hallucinations (peyote, marijuana, morning glory seeds)
May also be narcotic
Narcotic Compounds
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By definition a narcotic drug induces central nervous
system depression resulting in numbness, lethargy,
sleep
In current use, a narcotic is a psychoactive drug that
is dangerously addictive
Addictive compounds elicit: psychological
dependence, physiological dependence, and/or
tolerance
Psychoactive Compounds
Stimulants Depressants
Hallucinogens
Cocaine
Opiates
THC (Marijuana)
Ephedrine
Heroin
Mescaline
Nicotine
Alcohol
Psilocybin/Muscarine
Khat
Kava lactones
Ergot alkaloids (LSD)
Betel nuts
Tropane alkaloids
Caffeine
Salvinorin
Stimulants
Compounds that excite or enhance
psychomotor activity
Cocaine
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Major alkaloid in the coca plant
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Erythroxylum coca
Erythroxylum novogranatense
Small trees in genus Erythroxylum (Family
Erythroxylaceae) native to Andes Mts. in
South America
Ethnobotany and history
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Cocaine use by the Incas
Spanish conquest
Introduction to Europe
US – 19th century
Late 20th and 21st centuries
Sources of cocaine
Forms of Cocaine
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Cocaine hydrochloride
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Hydrochloride salt, or powdered form of cocaine,
dissolves in water
Can be taken snorted or taken intravenously
Freebase
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Compound that has not been neutralized by an acid to
make the hydrochloride
Hydrochloride is heated with water and sodium
bicarbonate to form crack which is usually smoked
Cocaine Structure
Mode of Action on CNS
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Region most affected - deep within the brain (ventral
tegmental area)
Nerve cells originating there extend to the nucleus
accumbens (one of the reward centers)
At the synaptic level, cocaine blocks the re-uptake of
dopamine results in a build up of dopamine in the
synapse which contributes to the high - later
dopamine is depleted
Blocks reuptake of norepinephrine
a and b adrenergic receptors activated
Action of cocaine on CNS
Effects of Cocaine
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Increased energy
Decreased appetite
Mental alertness
Increased heart rate and blood pressure
Constricted blood vessels
Dilated pupils
Increased temperature
Highs from cocaine
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Duration of cocaine's euphoric effects depends on
the route of administration
The faster the absorption, the more intense the high
BUT the faster the absorption, the shorter the
duration of action
High from snorting may last 15 to 30 minutes, while
that from smoking may last 5 to 10 minutes (high
from smoking starts in 10 sec)
Increased use can reduce the period of stimulation
Negative effects of cocaine use
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Addiction
Tolerance
Cardiovascular effects
Direct effects on the heart
Respiratory problems
Psychological effects