CNS depressants: chapter 13 Flashcards
mechanism of action of benzodiazepines
depress cns activity in the hypothalamic, thalamic, and limbic systems
what receptors do benzodiazepines have an effect on
GABA receptors
do benzodiazepines increase liver metabolism
no
indications for nonbenzodiazepines
short term treatment of insomnia
indications for benzodiazepines (5)
sedation, relieve anxiety, skeletal muscle relaxation, acute seizures disorders, symptoms of alcohol withdrawal
2 contraindications for benzodiazepines
narrow angle glaucoma, pregnancy
4 adverse effects of benzodiazepines
depressed cns, fall hazard, hangover effect, development of tolerance/dependance
4 symptoms of benzodiazepine toxicity
somnolence, confusion, coma, diminished reflexes
what is the antidote for benzodiazepines
flumazenil
which benzodiazepine is long acting
diazepam
indication for diazepam (4)
anxiety, sedation, anticonvulsant therapy, skeletal muscle relaxation
which benzodiazepine is intermediate acting
lorazepam
2 indications for lorazepam
anxiety, acute seizure activity
which benzodiazepine is short acting
midazolam
indication for midazolam
preoperative and procedural sedation
which drug is a nonbenzodiazepine
zopiclone
is zopiclone long, intermediate, or short acting
short
indication for zopiclone
short term treatment of insomnia
why are barbiturates not commonly used
preference for benzodiazepines and low therapeutic index
2 mechanisms of action of barbiturates
inhibit nerve impulse transmission, inhibit GABA
2 effects of barbiturates
sedative, hyponotic
3 contraindications for barbiturates
pregnancy, significant respiratory difficulties, severe kidney or liver disease
3 adverse effects of barbiturates
vasodilation and hypotension if given rapidly, respiratory depression
what does overdose of barbiturates cause
cns and respiratory depression
what are the first signs of barbiturate overdose
cold, clammy skin or hypothermia
what are the later signs of barbiturate overdose (3)
fever, tachycardia, hypotension
what is the treatment for barbiturate overdose (5)
supportive measures such as ensuring airway, ventilation, and giving o2, fluids, and pressors
what substance can be administered for barbiturate overdose (this is not an antidote). why is this substance administered
activated charcoal to draw drug molecules from circulation into the GI tract for elimination
what drug is a barbiturate
phenobarbitol
is phenobarbitol long, intermediate, or short acting
long
3 indications for phenobarbitol
seizures, convulsions, hyperbilirubinemia in neontates
3 OTC hypnotics
doxylamine, diphenhydramine hydrochloride (sleep-eze), acetaminophen/diphenhydramine hydrochloride (extra strength tylenol nighttime)
what should not be used alongside OTC hypnotics. why
alcohol due to risk of respiratory depression or arrest
what do muscle relaxants do to the cns
cause cns depression
how does cns depression caused by muscle relaxants have an effect on the body (4)
relax skeletal muscles, cause mild weakness, decrease force of muscle contraction, reduce muscle stiffness
mechanism of action of baclofen
depress nerve transmission in the spinal cord
4 adverse effects of baclofen
lightheadedness, fatigue, confusion, muscle weakness
treatment for baclofen overdose (4)
supportive measures such as gastric lavage, maintaining airway, ecg monitoring, and iv fluids
indiction for baclofen
treat chronic spastic muscular conditions
what is another muscle relaxant besides baclofen
cyclobenzaprine
indication for cyclobenzaprine
reduce spasms after msk injuries
how can you minimize gi upset when taking cns depressants
take with food
what may occur 3-4 weeks after initiation of benzodiazepine therapy
rebound insomnia
when is the chance of hypotension the greatest with muscle relaxants
within 1hr of dosing
why must RBC count, hemoglobin, and hematocrit be monitored with barbiurates
chance of anemia
what must be done when there is long term use of barbiturates
monitoring of therapeutic drug levels
indications for kava (3)
relieve anxiety, stress, and restlessness
3 adverse effects of kava
skin discolouration, papillary enlargement, scaly skin
what risk does kava pose in terms of the liver
severe liver damage and toxicity
6 contraindications for kava
parkinsons, liver disease, depression, alcoholism, pregnancy, breastfeeding
3 indications for valerian
relieve anxiety, restlessness, sleep disorders
3 adverse effects of valerian
cns depression, hepatotoxicity, insomnia
2 contraindications for valerian
heart and liver disease