Stimulants B&B Flashcards
what are the 2 physiological effects of cocaine?
- local anesthetic (Na+ channel blocker)
- inhibits monoamine reuptake (dopamine, 5HT, NE) —> sympathetic activation
what is the classic hallucination of cocaine intoxication?
tactile hallucination - “bugs crawling on skin”
what is the treatment for cocaine intoxication? what drugs should be avoided?
tx with benzodiazepines - CNS depressants, counteract stimulatory effect of cocaine
AVOID beta blockers - further increase unopposed alpha adrenergic activity, worsen HTN and chest pain
how do amphetamines increase synaptic NE and dopamine?
promote release AND inhibit reuptake
what is the treatment for amphetamine intoxication?
tx with benzodiazepines - CNS depressants, counteract stimulatory effects
caffeine is an antagonist of ______ receptors, which leads to…
caffeine (methylxanthine) is an antagonist of ADENOSINE receptors, which leads to release of dopamine and NE
also blocks renal adenosine receptors —> diuresis
[recall adenosine = vasodilator, used in chemical stress tests]
where are nicotinic ACh receptors found?
- between pre- and post- ganglionic neurons in sympathetic nervous system
- adrenal medulla
- between pre- and post- ganglionic neurons in parasympathetic nervous system
- post synaptic neurons in skeletal muscle
which antidepressant is used in smoking cessation? how does it work?
bupropion: antidepressant, blocks reuptake of NE and dopamine
what is the clinical use of varenicline?
partial nicotinic receptor agonist used for smoking cessation
agonists effects limit withdrawal symptoms, antagonist effects block nicotine
AE: nausea, sleep disturbance
What are the EEG findings of each of the sleep stages?
awake, eyes open = beta waves (low amplitude, high frequency)
Awake, eyes closed = alpha waves (increased amplitude, more synchronous)
N1 = lightest sleep, Theta waves
N2 = largest percentage of sleep, Theta waves + K complexes (sudden increase in amplitude) + sleep spindles (sudden increase in frequency)
N3 = deepest sleep, delta waves (lowest frequency, highest amplitude - “slow waves”) - sleepwalking/talking/bedwetting occurs here
REM = low voltage sawtooth pattern, coordinated by PPRF - muscle paralysis occur is here (sleep paralysis also occurs here)
what sleep changes occur in depression? (3)
- decreased REM latency – REM sleep starts quicker
- Increased total REM sleep
- decreased N3/slow wave sleep
[sleep rhythms normalize on antidepressants]
What is the clinical use of modafinil?
treats narcolepsy by promoting wakefulness - controlled substance, risk of abuse
Name two indirect sympathomimetics that treat both ADHD and narcolepsy
- methylphenidate
- amphetamines
both increase dopamine and NE in synapses
What is the clinical use of sodium oxybate?
Salt form of gamma hydroxybutyrate (GABA metabolite) that causes CNS depression
Reduces cataplexy caused by narcolepsy, also improves nocturnal sleep and reduces daytime sleepiness
Illegally used as date rape drug
describe the MOA of amphetamine, dextroamphetamine, methamphetamine, and lisdexamfetamine
- enter presynaptic dopaminergic neurons both directly and via DAT and NET transporters
- pumped inside intracellular vesicles via vesicular transporter (VT), displacing DA and NE
- this causes massive outflow of DA and NE into synaptic cleft
—> in prefrontal cortex, enhance alertness/ concentration + reduce hyperactivity/impulsivity/ appetite
for what conditions are amphetamine, dextroamphetamine, methamphetamine, and lisdexamfetamine used to treat?
increase synaptic DA and NE, tx:
- ADHD - first line, both short-acting and long-acting have rapid onset of action
- narcolepsy - off-label
contrast the adverse effects of amphetamines in adults vs children
adults: dry mouth, insomnia, irritability, headaches, dysphoria (distress), weight loss; less commonly psychosis, priapism, tics; euphoric/psychoactive (Schedule II)
children: weight loss, poor growth, sleep disturbances, jitteriness, emotional lability, social withdrawal
what is the MOA and clinical use of methylphenidate (MPH)?
NE-5HT reuptake inhibitor (NRDI) - block DAT and NET —> affect prefrontal cortex to enhance alertness/concentration, reduce hyperactivity/impulsivity, suppress appetite
tx ADHD (1st line) and narcolepsy (2nd line)
name a NE-5HT reuptake inhibitor (NRDI) that treats both ADHD and narcolepsy
methylphenidate (MPH): block DAT and NET —> affect prefrontal cortex to enhance alertness/concentration, reduce hyperactivity/impulsivity, suppress appetite
schedule II controlled substance!
what is the MOA and clinical use of modafinil and armodafinil?
weak inhibitor of DA reuptake —> promotes wakefulness
treats narcolepsy (first line)
AE: headache, nausea, decreased appetite, insomnia, anxiety, diarrhea, Schedule IV
name an inhibitor of DA reuptake that is first-line for treating narcolepsy
modafinil, also armodafinil
MODify your sleep!
what is the MOA of caffeine?
competitive antagonist of adenosine receptors
adenosine is NT that activates sleep-promoting ventrolateral preoptic (VLPO) nucleus in the brain; builds up throughout the day as byproduct of cellular metabolism and causes feeling of tiredness
what are the effects (specifically) of caffeine on CNS, cardiovascular, renal, and GI systems?
CNS: decreases fatigue (antagonizes adenosine), mildly elevates DA and NE
cardiovascular: inotropic + chronotropic, short-term increase in BP
renal: mild diuretic
GI: increases acid (H+) secretion from gastric mucosa
what is the function of adenosine?
adenosine: NT that activates sleep-promoting ventrolateral preoptic (VLPO) nucleus in the brain; builds up throughout the day as byproduct of cellular metabolism and causes feeling of tiredness
caffeine antagonizes adenosine receptors
