MSK/CT Flashcards
what do LTC4, LTD4, LTE4 do?
leukotrienes
affect bronchial tone
what does LTB4 do?
leukotriene
increases neutrophil chemotaxis
what does PGI2 do?
prostaglandin
decreases platelet agg and vascular tone
what does PGE1 do?
prostaglandin
decreases vascular tone
what do PGE2 and PGF2 do?
increase uterine tone
what does TXA2 do?
increases platelet aggregation and vascular tone
what step of inflammatory cascade is blocked by corticosteroids?
phospholipase A2: production of arachidonic acid
what step of inflammatory cascade is blocked by zileuton?
lipoxygenase: blocks leukotriene production
what step of inflammatory cascade is blocked by montelukast, zafirlukast?
LTC4/LTD4/LTE4 receptor antagonists
block increase in bronchial tone
what step of inflammatory cascade is blocked by aspirin, NSAIDs?
COX1/COX2
blocks AA –> cyclic endoperoxide (precursor to PGs and TXA2)
acetaminophen MOA?
reversibly inhibits COX, mostly in CNS
inactivated peripherally
how does acetaminophen cause hepatic necrosis?
metabolite NAPQI depletes glutathione and forms toxic tissue byproducts in liver
** NAC regenerates glutathione
aspirin MOA?
IRREVERSIBLE inhib of COX1/2 by ACETYLATION
increases bleeding time
PT/PTT unaffected
** low dose –> platelets. medium dose –> antipyretic/analgesic. high dose –> anti-inflammatory
aspirin toxicity?
gastric ulceration
tinnitus
chronic –> ARF, interstitial nephritis, GI bleeds
- Reyes - in children with viral infx
- respiratory alkalosis –> mixed met acidosis and resp alkalosis
celecoxib?
COX2 inhibitor
spares platelet function
toxicity: increased thrombosis risk. sulfa allergies.
NSAID toxicity?
interstitial nephritis
gastric ulcer
renal ischemia
bisphosphonate MOA?
pyrophosphate analog
bind hydroxyapatite in bone –> OC activity inhibition
bisphosphonate toxicity?
corrosive esophagitis - sit up after taking
osteonecrosis of jaw
terparatide?
PTH analog (subQ) –> increased OB activity
- increased bone growth vs. bisphosphonates
- SE: transient hypercalcemia; maybe increased risk of osteosarcoma
allopurinol MOA?
converted to alloxanthine –> inhibits XO
** increased concentrations of azathioprine and 6MP
allopurinol uses?
gout
lymphoma and leukemia - prevent tumor-lysis nephropathy
pegloticase?
recombinant uricase: uric acid –> allantoin
probenecid?
inhibits uric acid reabsorption in PCT
can precipitate uric acid calculi
** inhibits PCN secretion in PCT as well
colchicine?
binds tubulin –> inhibit microtubule polymerization
impairs neutrophil chemotaxis and degranulation
gout: acute and ppx
salicylates in gout?
DON’T GIVE EM
depress uric acid clearance, especially at lower doses
what do TNFa inhibitors predispose to?
infection - esp TB reactivation
needed in granuloma formation and stabilization
etanercept?
fusion of TNFa rcptr and IgG1 Fc
used for RA, psoriasis, ankylosing spondylitis
infliximab, adalimumab?
anti-TNFa Mab
used in IBD, RA, ankylosing spondylitis, psoriasis
