Analgesics Flashcards
Peripheral pain stimulus is blocked by?
NSAIDs
Conduction of afferent peripheral nerve is blocked by?
Voltage gated sodium channel blockers; the “caines” (Lidocaine)
Spinal cord transmission of pain is blocked by?
Everything
Cortical modulation of pain is blocked by?
Opioids only
What are the NMDA receptor blockers and when are they typically used?
Ketamine, Dextromethorphan.. Used pre-surgery to prevent “Wind-up”
AE’s of Ketamine?
Hallucinations, amnesia, HTN, ICP
AE’s of Dextromethorphan?
Dizziness, confusion, fatigue. It is an antitussive
Carbamazepine MOA? What does it tx?
Voltage gated Na channel blocker. Tx: Trigeminal neuralgia, neuropathic pain (also recall that it tx depression in Huntington’s)
List the opiate antagonists
Naloxone, Naltrexone, Nalmefene
Which opioid antagonist treats overdose?
Naloxone
Which opioid antagonist is used in addiction programs?
Naltrexone (long half life); it also decreases alcohol cravings in alcoholics
What is the biggest reservoir for opiates?
Muscle
Where is the long term depot for opioids?
Adipose
What are the AE’s of opioids? There are a shit ton..
Restlessness, hyperactivity, convulsions, respiratory depression, N/V, increased ICP, ortho hypoTN, constipation, urinary retention, pruritis, bradycardia, miosis
Which AE’s are immune to tolerance?
Constipation, miosis, convulsions
When does N/V occur with giving opioids?
When you give them too quickly
When does respiratory depression occur with opioids?
When someone overdoses (reverse with Naloxone)
Which opioid causes histamine release?
Morphine (counter with anti-histamines)
Triad of opioid overdose?
Coma, respiratory acidosis, pinpoint pupils (give Naloxone)
Drug interaction w/ opioids?
*SAM: Sedatives, antipsychotics, MAOIs
Which opiate are you worrying about polymorphisms in CYPs or other drugs interacting with CYPs?
Codine.. Also, codine is contra’d in pregnancy & breastfeeding!!!
All opiates are contra’d in renal failure except which two?
Hydromorpone & Fentanyl
Which opioid is used to manage opioid withdraw due to its long half life?
Methadone (can be used in pregnant addicts); can cause decreased libido, prolonged QT
Which opioid can be given via transdermal patch or lozenge?
Fentanyl (remember, this drug is OK for renal failure)