Sedative - Hypnotic drugs Flashcards
what are the major inhibitory neurotransmitters?
GABA - CNS
glycine - spinal cord (ventral horn)
*monocarboxylic acids
difference between sedatives and hypnotics
Sedatives - reduce anxiety; calming effect
Hypnotics - produce drowsiness; onset and maintenance of sleep
more pronounced CNS depression
what are the major excitatory neurotransmitters?
glutamate and aspartate
- dicarboxylic acids
mechanism of action of BENZODIAZEPINES
binds to GABA-A receptor subunit and increases FREQUENCY of Cl channel opening
membrane hyperpolarization
what are the prototype drugs for short/intermediate/long acting BDZ?
short-acting – midazolam
intermediate acting –lorazepam
long acting – diazepam
what are the uses of midazolam?
acute anxiety, anesthesia induction, preop sedation
what BDZs can be used as tranquilizers and for seizure disorders?
intermediate acting - clonazepam
long acting - diazepam
what abnormal sleep pattern results from use if BDZs?
decreased REM sleep
Whhuch drugs are considered date-rape drugs?
- alcohol (most common)
- flunitrazepam (rohypnol)
- gamma hydroxybutyrate
BDZ with the longest half life
CHLORDIAZEPOXIDE
- 36-200hours half life
- longest spelling!!!
Side effects of benzodiazepines in general
ANTEROGRADE AMNESIA, decreased psychomotor skills, unwanted daytime sedation, respiratory depression, tolerance, dependence liability
midazolam exhibits TOLERANCE
Antidote for BDZ overdose
FLUMAZENIL
- a BDZ antagonist
bdz overdose - toxic dose is 1000x the therapeutic dose
ssx: slurred speech, ataxia, altered sensorium, respi depression
what is the noted side effect of flumazenil?
It can precipitate BDZ withdrawal syndrome
what can happen if Flumazenil was given to a patient who took both TCA and BDZ?
seizures and arrhythmias!!
Mechanism of action of BARBITURATES
binds to GABA-A receptor sites
increases DURATION of Cl channel opening
read as BarbiDURATes (duration); FRENzodiazepines (frequency)
what are the prototyoe drugs for barbiturates?
ultra-short/ short-intermediate/ long acting
ultrashort - thiopental (read as TAYOpental = TAYO agad!)
short - pentobarbital
long - phenobarbital
what is a unique side effect of barbiturates?
Acute intermittent porphyria
barbiturates increase production of d-ALA dehydratase
- accumulation of porphobilinogens
- urine darkens in exposure to light and air
what is the enzyme deficient in acute intermittent porphyria?
HMB synthase
what are unique uses of PHENOBARBITAL?
for seizure disorders, status epilepticus, hyperbilirubinemia (gilbert’s syndrome)
what Barbs drug is used for Gilberts syndrome?
phenobarbital
gilberts syndrome - disease that reduces the rate of bilirubin conjugation producing UNconjugated hyperbilirubinemia
barbiturates are potent ___________ of CYP450 enzymes
potent inducer
what is the only indication of use for Zolpidem?
Insomnia
zolpidem is an imidazopyridine
zolpidem/ zaleplon – zzzzzzZzzzzzzz Zzzleeep
what drug is used for Generalized anxiety disorder?
Buspirone
- a partial agonist at 5-HT1a receptors and poss D2 receptors
- not used in acute anxiety!!
