Sketchy Pharm: Opiates, Naloxone, Naltrexone Flashcards
What are the three kinds of opioid receptors?
Mu, kappa, and delta
Most of the effects of opioids are mediated by the _________ receptors.
Mu (Mu-ssage)
What type of receptor is the mu opioid receptor –and what is the effect of agonizing it?
It is a G-protein that leads to the closure of calcium channels and opening of potassium channels – particularly on neurons – which leads to the hyperpolarization of the membrane and lessened likelihood of action potential transmission. (Think of the open banana barrels and the closed Cali-Yum cooler.)
Which neurons are most susceptible to opioid stimulation?
Presynaptic neurons (the guy unplugging the presynaptic extension cord)
_________ is a weak mu-opioid agonist.
Tramadol (the tramadol train in the background – the background representing weakness)
Fentanyl and morphine stimulate ___________.
the mu-receptor (MORe fuN; make your pain a FaNTAsy)
Why is tramadol such a great drug for neuropathic pain?
Because it is not only a weak mu-opioid agonist, it also inhibits the reuptake of norepinephrine and serotonin!
Which parts of the GI tract have mu-opioid receptors?
Stomach, small intestine, and large intestine
What physical property makes loperamide an interesting and useful opioid?
Loperamide (lop-eared rabbits) cannot pass through the BBB and so has no analgesic effects. It can, however, be used as a great anti-diarrheal.
What is another drug with similar properties to loperamide?
Diphenoxylate (the dolphin fountain)
Codeine is an _____________.
opioid antitussive
What drug, like codeine, is an opioid that suppresses cough?
Dextromethorphan (the dextromethorphan orphan – mascot of the cough drops)
There is another mnemonic on the cough-drop bag with the dextromethorphan orphan. What is it?
The camel! It represents NMDA (because camels are nomadic) and it is tethered to a post – symbolizing how dextromethorphan antagonizes NMDA receptors.
What are the side effects of opioids?
CNS depression, causing respiratory depression
Miosis (hoodie)
Constipation
Most of the effects of opiates develop tolerance, but two do not. What are they?
Miosis and constipation (these are big, remember!); this is represented by the janitor showing that not all are tolerated
What is the phenomenon of opioid hyperalgesia?
The reason it occurs is not known, but some patients develop hyperalgesia with chronic opioid use.
What are the symptoms of opioid withdrawal?
Lacrimation Salivation Diarrhea Mydriasis Anxiety Hyperventilation Hyperthermia
All things opposite of what opiates do.
Methadone is a potent opioid agonist. Why not just give them morphine or heroin?
Methadone has a loooooong half-life and thus the withdrawal effects of methadone are not as acute (think of the long tapering flag above the DONE timer where the guy is getting out of the withdrawal pool).
What is a partial agonist that is used to treat opiate withdrawal?
Buprenorphine (the buprenorphine blueprint)
The partial mu-opioid agonists have what commonality in their names?
Bu-phine: buprenorphine, nalbuphine, and butorphanol
Think of the Blue Fin grill with the partial massage (the foot massage)
The two mu-opioid antagonists are ____________.
naloxone (no lax zone –don’t relax) and naltrexone (no tricks zone)
