Drugs Flashcards
Psychoactive drugs
drugs that influence subjective experience and behavior by acting on the nervous system
-go pass the blood brain barrier
Drug metabolism
conversion of drug from active to non-active form
Drug Tolerance
- Decreased sensitivity to a drug as a consequence of exposure to it
Cross tolerance
exposure to one drug can produce tolerance to similar drugs
Metabolic
tolerance
Less drug is getting to the site of action
Functional drug tolerance
Decreased responsiveness at the site of action, fewer receptors, decreased efficiency of binding at receptors, receptors less responsive
Contingent drug tolerance
Tolerance only develops to drug effects that are experienced
Conditioned drug tolerance
Maximal tolerance effects are seen in the environment in which a drug is usually taken
EX: going to the same place to take drug…body will prepare itself and try to compensate for it
What kind of drug is tobacco?
a stimulant
Parts of the brain effected by nicotine
- Increases Dopamine in the mesocorticolimbic system
- Activates a subclass of acetylcholine receptor called nicotinic receptors
- These receptors are widespread and are on presynaptic terminals of DA-releasing, Ach-releasing, and glutamate-releasing neurons
what kind of drug is Alcohol
depressant
How alcohol effects the brain
Increases DA in the mesocorticolimbic system
- Reduce calcium flow in neurons (reducing the amount of NT being released…making brain less excited and forgetful memory)
- Acticates GABA….hyperplorizes cell…inhibits neurons
Triggers apoptosis-cell death!
Severe alcohol withdrawal in three phases:
5-6 hrs post-drinking: tremors, nausea, sweating, vomiting, etc.
15-30 hrs: convulsive activity
24-48 hrs: delirium tremens – may last 3-4 days
Antabuse, or disulfiram alcohol treamtment
drug that interferes with the metabolism of alcohol
produces an accumulation of acetaldehyde in the bloodstream
Marijuana in high doses
High doses impair short-term memory and interfere with tasks involving multiple steps
Weed and the brain
- effects on cannabinoid receptors
- cannabinoid receptors found in presynaptic nerve terminals
- act to Ca2+ influx and facilitate K+ channels
- inhibits neurotransmitters
Possible correlation between marijuana use ….
schizophrenia
Medicinal Uses of Marijuana
Treats nausea
Blocks seizures
Dilates bronchioles of asthmatics
Decreases severity of glaucoma
Reduces some forms of pain (tolerance of)
Brain on Cocaine
Blocks reuptake of dopamine, noremnephrine, and serotonin , promoting happiness and spazziness
increases dopamine in the mesocortilimbic system
unique to cocaine…
stumulant
Do not develop tolerance…you may be more sensitive to convulsive effects
Too much cocaine leads to cocaine psychosis- paranoid symptoms
Coke heads use it in binge
Although highly addictive, withdrawal is relatively mild
MDMA (“ecstasy”)
stimulant
Impairs executive function, inhibitory control, and decision making (as shown by cortex and limbic functional brain scan abnormalities)
Methamphetamine
stimulant
low dosages – increased alertness, concentration, and energy
high doses - mania with accompanying euphoria, feelings of self-esteem and increased libido
Highly addictive
meth in the brain
Causes DA, NE, and 5HT to release into synaptic cleft
Indirectly blocks reuptake of DA, NE, and 5HT
what kind of drugs are Heroin and Morphine?
opiates
