Pharm
Pharm Chapter 36 NSAIDS
Aspirin mechanism of action
Acetylates COX 1 and COX 2 which results in reduced prostaglandin and
thromboxane synthesis which leads to reduced inflammation.
Effects of aspirin
Reduces inflammation
Reduces fever due to inhibition of prostaglandins in the CNS
Analgesic
Clinical uses of aspirin
Low dose is effective in recucing platelet aggregation
Intermediate doses have antipyretic and analgesic effects
High doses are used for anti inflammatory effect
Nonselective NSAIDS
Ibuprofen
Reversibly inhibits COX 1 and COX 2 and results in rediced prostaglandin
synthesis
Used for analgesia, antipyretic, antiinflamm, close of patent ductus arteriosus
Tox: Gi tox(less compared to aspirin)
Nephrotox
Interferes with aspirins antithrombotic action
Aspirin toxicities
Gi tox
Nephrotox
Increased bleeding time
Bronchoconstirction
Tinnitus
Hyperventilation
Metabolic acidosis
Coma
Cox02 selective inhibitors( celecoxib, rofecoxib,
valdecoxib)
Selective reversible inhibition of COX 2 which results in decresed prostaglandin
snynthesis
Used for same reasons other NSAIDS
Tox : Neprhotox, less risk of GI tox, greater risk of thrombosis compared to
nonselective nsaids, leukitrine reaction
Acetaminophen mech of action
Non annti inflammatory analgesic
Weak COX 1 and COX 2 inhibitor
May inhibit COX 3 in CNS
Effects and clinical use of acetaminophen
Analgesic and antipyretic
Used as a subsitute of aspirin especialy in children
Unaffected by renal disease
Tox of Acetaminophen
Hepatotox (antidote in acetylcysteine)
DMARDS
Methotrexate(DMARD)
inhibts dihydrofolate reductase
Used as an anticancer and rheumatic drug
Causees nausea, mucosal ulcer, hematotox, hepatotox, teratogen
Infliximab(DMARD)
Ant tnf alpha
used for RA
Tox; Oppurtunistic infections and reactiviation of latent TB and HIV
Increase risk of SKIN cancer
Drugs used in gout
Reducin inflammation with :Colchine, NSAIDS or glucocorticoids-
Accelarating renal excretion of uric acid with uricosuric drugs
Reducing conversion of purines to uric acid by xanthine oxidase.
Colchine
Inhibitoon of microtubule assembly which decreasess macrophage migration and
phagocytosis.
Treats chronic and acute gout and familial mediteranean fever
tox: diarhea, sever liver and kidnye damage in overdose
Indomethacin
NSAID which is effective for treatemnt of acute gouty arthiritis.
Uricosuric agents
Probenecid, sulfinpyrazone
Mech of action of Uricoserics
Competitveyl inhivts renal absorption of uric acid
Treats chronic gout and used for prolongation of antimicrobial drig action
low doses may elevate serum uric acid conc.
Tox of uricoseric drugs
Acute gout during earyl phase which may be precipated by administering
colchine or indomethacin
Xanthine oxidase inhibitors
Allopurinol, febuxostat
Ireeversible inhibits xanthine oxidase and lowers uric acid(prevents convertsion
xanthine to uric acid)
Febuxostat is reversivle
Effects of allopurinol and febuxostat
IReduces uric acid therefore less likelyhood of precipitation of uric acid crystals in
jointx and tissues.
Used for chronic gout, adjunct to cancer chemotherapy
Tox of allopurinol and febuxostat
GI upset
Hypersens
Bone marrow suppression
URicase drugs(Pegloticase)
Mammalian uricase which converts uric acid to soluble allantoin.
Treats chronic refractory gout
Tox: Gout flare due to rapid change in uric acid levels. Prophylacis of this is with
NSAIDS or colchicine
