Drugs of Abuse 1 Flashcards
Glutamate
primary excitatory neurotransmitter of CNS found in almost all neurons that act on glutamatergic neurons important for learning
GABA
primary inhibitory neurotransmitter of CNS found in high conc. in cerebrum, hippocampus and cerebellum
ACh
excitatory neurotransmiter that acts on nicotinic receptors (stimulated by ACh or nicotine) and muscarinic receptors (stimulated by ACh or muscarine) involved in learning, memory and cognitive function
Catecholamines
dopamine- involved in some hormonal systems, motor coordination, and motivation and reward; norepinephrine- bind alpha and beta receptors and activation leads to excitation
Serotonin
hyperactivity of this system leads to anxiety and hypoactivity leads to depression
Opioid Peptides
enkephalins, endorphins and dynorphins that bind to mu, delta and kappa receptors
Dopamine hypothesis
main hypothesis to explain addiction; drugs of abuse increase dopamine in limbic system which is also responsible for natural rewards such as food, sex and stimulus related rewards
Criteria for substance abuse
use of prohibited drugs, alternate use of therapeutic drug, ingestion of larger doses of drugs or different route of administration, drugs taken in combo to produce pleasurable effects, excessive use of legal social drugs, use if non-therapeutic substances of abuse
Drug withdrawal
abnormal physiological state produced by repeated administration of a drug that leads to the appearance of a withdrawal syndrome when drug administration is discontinued
Drug Tolerance
state in which repeated administration of a given dose of a drug has progressively less pharmacological effect or dose needs to be increased to have the same magnitude
Drug Addiction
stopping or abruptly reducing the dose of a drug produces non-physical symptoms characterized by emotional and mental preoccupation with the drug’s effect (craving)
What are stimulant drugs? What are some examples?
increase the activity of the brain; amphetamines, cocaine, nicotine, caffeine
What are Amphetamines?
widespread controlled substances that are structurally similar to epi and norepi and increase the release of dopamine; includes amphetamine, dextroamphetamine and methamphetamine
CNS effects of amphetamines
decreased threshold for transmitting sensory input causing excitation of cerebral cortex that leads to restlessness, dizziness, confusion, tremors, sometimes panic and psychosis, euphoria, appetite suppression, and increased mood swings and aggression
Other Effects of amphetamines
short term: heart attack, angina, bp changes, increased respiratory rate, fever, stroke
long term: chronic sleeping issues, poor appetite, anxiety, psychosis, elevated bp and abnormal cardiac rhythm
Abuse potential and dependence of amphetamines
high abuse liability bc of powerful euphoria and quick onset of action (IV administration) and inherent harmfulness due to long-term effects
tolerance develops to everything but therapeutic effects and psychosis, strong dependence and addiction develop
Therapeutic uses of Amphetamines
Ritalin (related compound) used to treat ADHD and Narcolepsy as opposed to amphetamines bc of reduces cardiovascular and appetite suppressing effects
Cocaine and its pharmacology
originates from leaves of coca bush and is a local anaesthetic and CNS stimulant that causes stimulation in a dose dependent manner by inhibiting re-uptake of dopamine and serotonin
Effects of cocaine on CNS
similar to amphetamines but have shorter duration of action and less complications w IV use bc it is sniffed or smoked
Long-term effects of cocaine
paranoia, hallucinations and sensation of insects crawling under skin, impaired sexual function, brain damage, high bp and irregular heart rhythm, changes to nasal mucosa
Abuse potential and dependence of cocaine
high abuse potential due to rapid and powerful euphoria, tolerance develops to mood-elevation but not psychosis, strong dependence and addiction develops
Therapeutic uses of cocaine
local anesthetic for mouth and throat but are rarely therapeutically used
Nicotine and its pharmacology
naturally occurs in tobacco; small particles absorbed when smoked and also absorbed through the GI tract, oral mucosa and across the skin to rapidly gain access to the brain
Effects of Nicotine on CNS
stimulates nicotinic receptors to increase dopamine and serotonin release and increases psychomotor activity, cognitive function, attention and memory and can lead to agitation, tremors and seizures in large doses