drugs of abuse Flashcards
List the drugs of abuse that are CNS depressants
- Alcohol
- Benzodiazepines
- Barbiturates
- Opioids
List the drugs of abuse that are CNS stimulants
- Cocaine
- Amphetamine
- Methamphetamine
- Nicotine
Physical Dependence
- Chronic drug use causes adaptations in brain chemistry (neuroadaptations).
- Intense physical disturbance when drug use is discontinued
Pscyhological dependence
- Drug use becomes a habit.
- A drug produces satisfaction and a drive to use it to avoid discomfort.
- Dysphoria and intense craving occur following the withdrawal of an abused drug.
differentiate between pharmacokinetic and pharmacodynamic tolerance
- pharmacokinetic: increased metabolism
- pharmacodynamic: receptor downregulation
differentiate between tolerance and sensitization. where does dose response curve shift
- Tolerance: more durg required to produce effect
- dose/reponse shifted to right
- Sensitization: increase of responsiveness after repeated use
- dose/response shifted to left
define addiction
- drug taken to alleviate craving/dysphoria
does physiological dependence mean addiction
No, need euphoric feeling to have addiction
What is the reward pathway
-
mesolimbic dopamine pathway
- ventral tegmental area (VTA) -> nucleus accumbens (NAc) -> Prefrontal cortex.
MOA of Amphetamines
- increases dopamine by reversing dopamine transport through the DAT (dopamine transporter)
Medical uses of amphetamines
- Narcolepsy and ADHD
- Ritalin and Adderall
withdrawal of amphetamines causes
- fatigue
- increased appetite
MOA of Methamphetamine (ICE, cystal meth)
- increases release of dopamine by reverse transport through DAT
- increases release of NE
- *both in basal ganglia
adverse effects of Methamphetamine
- amphetamine psychosis
- rapid physical and psychological dependence
- cardiac toxicity -> pulmonary edema and heart failure
- odor (hyperthermia)
- dental problems
- “Meth bugs”
Methamphetamine causes what to happen to dopamine transporters? What is the effect?
- loss of DA transporters
- slowing of motor response and memory impairment
MOA of Cocaine
- inhibits DA reuptake -> inc dopamine in synapse
- CNS stimulation
- craving can be severe
- physical and psychological dependence
chronic cocaine use leads to what
- reduction in overall brain activity
- “cocaine bugs”
- intense physiological dependence
Use of Bromocriptine in tx of cocaine addicts
- dopamine agonist
- decreases craving for cocaine
MOA of Nicotine
- activates nicotinic receptors (Na channels) in the CNS and periphery
- increases 5-HT and DA release
Metabolism of Nicotine
- metabolized by and induces CYP450s
Use of Bupropion in nicotine addiction
used to tx nicotine craving
MOA of MDMA “Ecstasy”
- increases 5-HT activity by blocking reuptake and stimulating 5-HT receptors
- not considered drug of abuse because does not affect reward pathway
adverse effects of MDMA “Ecstasy”
- hyperthermia, dehydration, kidney failures
- can lead to fatalities
list the effects during ecstasy and after
- during ecstasy -> increased 5-HT -> elevated mood
- after ecstasy -> decreased 5-HT -> depression like feelings, irritability
