Flashcards in gout drugs Deck (43)
what is the prevalence of gout?
Most common cause of inflammatory arthritis in the US (not autoimmune)
Most common rheumatic disease of adults
how is gout dx?
synovial aspiration (gold standard) :Seen via monosodium urate crystals
more commonly- can see on PE
what is gout?
protein metabolism product-->uric acid
too much protein breakdown or the diminished kidney function (where uric acid is excreted)
--> uric acid increases ( in blood tissues)
When it deposits in the joint it is called gout.
can you have hyperuricemia without gout?
yes! (if uric acid >6 = hyperuricemia) BUT if its not in the joints then its NOT gout
common presentation of gout
Painful, red, swollen inflammation of a joint (common area is first toe)
who usually gets gout?
poor diet (alcohol, fish, red meat, soda)
what drugs can CAUSE hyperuricemia?
Thiazide diuretics (HCTZ)
Ethambutol (TB drug)
Pyrazinamide (TB drug)
what is a Ddx that must be ruled out when suspecting gout?
3 drugs for acute txt of gout
prophylatic urate lowering therapy
1. uricosuric agents
2. xanthine oxidase inhibitors
3.Recombinant Urate-Oxidase Enzyme
what are the three uricosuric agents?
Probenecid - no longer used
what are the two xanthine oxidase inhibitors?
what are the two recombinant urate-oxidase enzyme drugs?
MOA of allopurinol
MOA: Inhibits Xanthine Oxidase (XO) preventing the conversion of xanthine to uric acid
what is allopurinol or febuxostat (uloric) used for?
uric-acid lowering therapy, as prophylaxis for gout
but of the two, allopurinol ALWAYS better choice.
ADRs of allopurinol
SJS, Hepatotoxicity, Hemolytic anemia (G6PD)
dosing for allopurinol
starts at 100mg daily and titrated to maximum 800mg/day
***Goal is Uric Acid < 6
(full effect 2-3 months)
why should allopurinol ONLY be used for prophylaxis of gout?
Can precipitate flare if given during active flare d/t mobilization of uric acid
MOA of febuxostat (uloric)
MOA: similar to Allopurinol (XO inhibitor) - just more specific but DOESNT mean its better
ADRs of febuxostat
Hepatotoxicity, SJS, CV events
(worse CV -thrombotic- events than allopurinol)
MOA of probenecid?
Inhibits tubular reabsorption of urate causing excretion of uric acid (uricosuric drug)
when is probenecid used for gout?
really not ever anymore
(due to need for adequately functioning kidneys, adequate hydration, and drug-drug-interactions)
MOA of pegloticase
Enhances the oxidation of uric acid to allantoin which is readily excreted through the urine (uricosuric drug)
what do you need to do to preven the MAJOR adr of pegloticase ?
premedicated with antihistamines and corticosteroids before administration (b/c of anaphylaxi risk)
2 ADRs of pegloticase
Anaphylaxis, CHF exacerbation
what is rasburicase used for? MOA?
similar MOA to pegloticase and only indicated for Tumor Lysis Syndrome (TLS) - chemotherapy use
NSAIDs for gout?
relieving the inflammation gout crystals cause
*Indomethacin, *naproxen, and sulindac favored but any will do
corticosteroids for gout?
Intra-articular injections indicated if gout present in a single joint
Oral steroids indicated for multiple joints or large joint involvement
MOA of colchicine?
inhibits polymerization of beta-tubulin into microtubules (dis-assemble structure- so more neutrophils can’t be assembled and draw more to the area)