Pharmacology: Narcotics Flashcards
nociceptive pain can be divided into ___ or __ pain
somatic or visceral pain.
visceral pain
contant, aching squeezing, harder to localize, can be referred
somatic pain/parietal pain
constant or intermitten, gnawing, aching, usually well localized. Sharper.
neuropathic pain can be ___ or ___
dysesthetic or neuralgic.
overall, neuropathic pain is due to damage to nervous system and causes the sharp nerve pains. due to destruction, infiltration, compression of nerve tissue.
neuralgic pain
lancinating, sharp shooting pain.
dysesthetic pain
burning, contant allodyniec pain.
acronym for assessing pain
WWQQAAAT: Where, when, quality (peritonitic or diffuse), quantity (1-10), aggravating, alleviating, associated symptoms, timeline/disease progression
T/f neuropathic pain is harder to treat
true. it’s resistant to treatment and there are limited surgical interventions.
opiates vs opioids
opiates= naturally present in opium– morphine, codeine, thebaine
opioids= manufacture- semisynthetic are derived from an opiate (heroin from morphine)
- some opioids are 100% man made like fentanyl and methadone.
what factors affect pharcokinetics vs pharmacodynamic
kinetics: absorption, distribution, metabolism, excretion
dynamics: receptor binding, signal messaging, physiological effects.
why is the effect of a given dose less after oral rather than parenteral administration
due to significant first pass metabolism
bioavailability =
fraction of the administered dose of a drug that reaches the systemic circulation in an active form
specificity of a test
probability that the test will be negative for someone who doesn’t have the disease
sensitivity of a test
the ability of a test to correctly identify those with the disease (true positive rate),
ppv
positive predictive value; the is the probability that subjects with a positive screening test truly have the disease.
morphine gets conjugated with ___ acid to form a pharmacologically inactive metabolite, ____
conjugates with glucoronic acid to form 3-glucuronide. forms the principal metabolite. (6- glucuronide form is more active than morphine)
has a longer half life
Systemically it is about 2X as potent as morphine
Intrathecally, it is about 100X more potent than morphine
primary method of morhphine excretion
morphine is excreted by the kidney in the form of 3-glucuronide.
morphine causes PEAR:
P = physical dependence E= euphoria A= analgesia R= respiratory depression
examples of full agonists, partial agonists, antagonists to Mu receptor
full agonist: morphine, hydromorphone, oxycodone, fentanyl
partial agonist: buprenorphien
antagonist: naloxone or naltrexone.
T/F you should use a long acting formulation for opioid naive patients
false. to avoid dependence, opioid naive patients should receive short-acting formulations
T/F opioids should be given IM
no. never!
preferred route is oral. When unable to swallow, IV or transdermal.
what is breakthrough analgesia
done usually in chronic pain patients when schedule dosing (ex/ every 4 hours) is required, then as per needed (PRN) dosing for episodes of increasing pain.
by how much should you titrate the opioid dose if the original dose is not giving pain control?
increase the dose by 25-50% if the patient is not achieving adequate pain control.
neurotoxicity of opioids
anxiety, agitation, restlessness, delirium. Not reversible with naloxone.
T/F narcosis is reversible with nalozone
true. narcosis is deep sedation, hypotension and decreased ventilation which can be reversed.
T/F neurotoxicity is reversible with naloxone
false. the anxiety and agitation and delirium opioids can cause are not reversible with naloxone.
