032415 anti-anxiety agents Flashcards
slow wave sleep has what neurotransmitter involved
serotonin
REM sleep has what neurotransmitter involved
NE
tx of anxiety and insomnia
- benzodiazepines and related drugs (most commonly used)
- SSRIs (commonly used for anxiety)
- buspirone
- classical antihistamines
- alcohol, cannabis, opiates
- barbiturates
GABA localization
substantia nigra globus pallidus hippocampus limbic structures-amygdala hypothalamus spinal cord
GABA receptor
Cl ion channel that when Cl enters, hyperpolarizes neuron and makes it less likely to fire
benzodiazepines’ MOA
binds alpha subunit of the Cl channel. enhances GABA’s actions at the GABA receptor (causes more hyperpolarization per amt of GABA)
flumazenil
blocks action of benzodiazepines at the GABA receptor
used for overdoses of benzos, or for waking up from surgery
buspirone’s MOA
partial agonist of 5HT1A-inhibits adenylate cyclase and opens K channel
also binds dopamine receptors
alprazolam vs diazepam vs buspirone
alprazolam and diazepam depress the CNS and create dependence. they are both BDZ. alprazolam is short duration. diazepam is long duration.
buspirone produces little sedation and has no dependence. it has delayed onset
role of lipophilicity of benzodiazepines
diazepam has high lipid solubility-so rapid absorption into brain–has FAST onset of action.
lorazepam is less lipid soluble than diazepam, so absorption is slower. it has a longer duration of action after a single dose.
lipophilicity determines quick vs slow onset
metabolism of benzodiazepines
chlordizepoxide, DIAZEPAM, prazepam, chlorzepate get converted to desmethyldiazepam, which is an active metabolite and has LONG HALF LIFE.
OXAZEPAM, LORAZEPAM, alprazolam and triazolam don’t have active metabolites
CNS effects of BDZ
decreased anxiety sedation hypnosis muscle relaxation anterograde amnesia (IV)-dental work, colonoscopy anticonvulsant minimal CV and respiratory actions
drug interactions of BDZ
additive CNS depressionw most other depressant drugs (alcohol, etc)
drugs that affect hepatic metabolism like cimetidine
drug of choice for sleep disorders
BDZ
BDZ used for alcohol withdrawal
chlordiazepoxide