Pharm- Sleep disorders and Anxiety Flashcards
what 2 classes of drugs act on GABA type A receptors?
Barbiturates and benzodiazepines
barbiturates?
barbiturates act on the beta subunit of GABA a;
they have a lower therapeutic index;
at higher doses they directly antagonize GABA and lead to anesthesia, coma, death
intermediate acting is pentobarbitol, short acting is thiopentol (used for anesthesia)
metabolism: in liver, and depends on redistribution from from CNS into muscle and fat
OD treatment: supportive (vent, lavage, charcoal), NEVER GIVE CNS STIMULANT TO COUNTERACT IT
benzodiazepines?
larger therapeutic index and less side effects than barbiturates
doesn’t activate GABA-R/ inhibit AMPA-R/ inhibit nAChR at higher doses like barbiturates
depressant actions are additive, don’t use with alcohol
alprazolam–anxiety
diazepam (valium)–anxiety, muscle relaxation, epilepsy
lorazepam–anxiety, epilepsy
midazolam–pre-op and operative anxiolytic
metabolism: by CYP3A4, many metabolites are still active, lorazepam is only one which doesn’t have active metabolites
non-benzodiazepines (z drugs)?
zolpidem (ambien), aszopiclone (lunesta), zaleplon (sonata)
hypnotic but not anxiolytic because they only target BZ1 subtype of bezodiazepine sites
initially cause memory problems
can be habit forming (eszopiclone is the only long term drug)
benzodiazepine antagonist?
flumazenil
melatonin agonist?
ramelteon
promotes falling asleep but not sleep maintenance
CYP metabolized
side effect: increased prolactin, can lead to infertility if chronic
sedating antidepressants?
amitryptiline, doxepine (TCAs)
trazodone, mirtazapine (miscellaneous class anti d’s)
gamma hydroxybutarate (aka sodium oxybate)
both a metabolite and precursor for GABA
through unkown mechanism can treat narcolepsy
schedule 1 controlled substance, it’s so abused and used as a date rape drug
direct acting spasmolytic and another use of it?
dantrolene
treats malignant hyperthermia
other spasmolytics?
tizanidine, baclofen
