Flashcards in Neuro drugs I Deck (17):
How do opioid analgesics work?
act at mu opiod receptors. alter synaptic transmission by opening K channels and closing Ca2+ channels. this decreases synaptic transmission and inhibits the release of ACh, norepinephrine, 5-HT, glutamate, and substance P
Apart from pain, what are some uses of opioids?
cough suppression (dextromethrophan), diarrhea treatment (loperamide), acute pulm edema
How do you treat opioid toxicity?
naloxone or naltrexone, which are opioid receptor antagonists
What is butorphanol?
this is a PARTIAL mu opiod receptor agonist. It is a kappa opioid receptor agonist. it produces anagesia but causes less resp depression than full opioid agonists. However, it can cause opioid withdrawal in a patient who is also taking a full opioid agonist, and can't be easily reversed with naloxone
What should I know about opioid receptor types?
What is the mechanism and toxicities for tramadol?
weak opiod agonist. also inhibits serotonin and NE reuptake. good for chronic pain. toxicities: decreases seizure threshold and can cause serotonin syndrome
How do barbiturates work?
facilitate GABA action by increasing the DURATION of Cl channel opening. neuron firing decreases.
Toxicities and contraindications of barbiturates?
contraindicated in porphyria. can cause respiratory and CV depression
How do benzodiazepines work?
facilitate GABA-A action by increasing the frequency of Cl channel opening. decreases REM sleep. many have long half-lives and active metabolites (but not triazolam, oxazeam, midazolam- so these three have greater addictive potential)
Which benzos are used for status epilepticus?
lorezepam and diazepam
How do you treat benzo toxicity?
flumazenil (competitive antagonist at the GABA benzo receptor)
What are the non-benzodiazepine hypnotics and how do they work? treatment of toxicity?
zolpidem (ambien), zaleplon, (eszopiclone)
work by binding the BZ1 subtype of GABA receptor, and may be reversed by flumazenil
used for insomnia
What are the inhaled anesthetics and what is a major complication? Effect on blood flow to the brain?
halothane, enflurane, methoxyflurane, nitrous oxide, among others. increase cerebral blood flow
all but nitrous oxide can cause malignant hyperthermia- inhaled anesthetics and succinylcholine induce fever and muscle contractions.
Thiopental: class, uses, effect on blood flow
highly potent, high lipid solubility, rapid entry to bran. used for induction of anesthesia and short procedures. decreases cerebral blood flow. effect terminated by rapid redistribution to the tissues
Midazolan: class, uses
most common drug for endoscopy. may cause severe post-op resp depression, decrease BP (treat OD with flumazenil), and anterograde amnesia
Ketamine: class, function, effect on blood flow
PCP analogues. block NMDA receptors. act as CV stimulants. cause disorientation, hallucination, and bad dreams. increase cerebral blood flow