MSK/Skin Flashcards
Acetaminophen
Mech:
Reversibly inhibits cyclooxygenase (in CNS)
Inactivated peripherally
Use:
Antipyretic, analgesic, NOT anti-inflammatory
Used instead of aspirin to avoid Reye syndrome in children with viral infection
Adv. effects: Overdose produces hepatic necrosis Acetaminophen metabolite (NAPQ1) depletes glutathione and forms toxic tissue byproducts in liver. N-acetylcysteine is antidote - regenerates glutathione
Aspirin
Mech:
NSAID that irreversibly inhibits cyclooxygenase (both COX-1 and COX-2) by covalent acetylation —> decrease synthesis of TXA2 and prostaglandins
Increase bleeding time
No effect on PT, PTT.
Effect lasts until new platelets are produced
Use: Low dose (2400mg/day) - anti-inflammatory
Adv. effects:
Gastric ulceration
Tinnitus (CN VIII)
Chronic use –> acute renal failure, interstitial nephritis, GI bleeding
Risk of Reye syndrome in children treated w/ aspirin for viral infection
Causes respiratory alkalosis early, but transitions to mixed metabolic acidosis-respiratory alkalosis.
Celecoxib
MOA:
Reversibly inhibits COX isoform 2 - mediates inflammation and pain
Spares COX-1 which helps maintain gastric mucosa, doses not have corrosive effects of other NSAIDs on GI lining
Spares platelet function as TXA2 prod. dependent on COX-1
Use:
Rheumatoid arthritis
Osteoarthritis
Adv. effects:
Increase risk of thrombosis
Sulfa allergy
NSAIDs
Ibuprofen, Naproxen, Indomethacin, Ketorolac, Diclofenac, Meloxicam, Piroxicam
MOA:
Reversibly inhibit cyclooxygenase
Block prostaglandin synthesis
Use:
Antipyretic, analgesic, anti-inflammatory
Indomethacin - used to close PDA
Adv. effects:
Interstitial nephritis, gastric ulcer (prostaglandins protect gastric mucosa), renal ischemia (prostaglandins vasodilate afferent arteriole)
Leflunomide
MOA:
Reversibly inhibits dihydrooratate dehydrogenase, preventing pyrimidine synthesis
Suppresses T cell proliferation
Use:
Rheumatoid arthritis
Psoriatic arthritis
Adv. effects: Diarrhea Hypertension Hepatotoxicity Teratogenicity
Bisphosphonates
Alendronate, Ibandronate, Risedronate, Zoledronate
MOA:
Pyrophosphate analogs
Bind hydroxyapatite in bone, inhibiting osteoclast activity
Use: Osteoporosis Hypercalcemia Paget disease of bone Metastatic bone disease Osteogenesis imperfecta
Adv. effects:
Esophagitis (if taken orally, ptns are advised to take w/ water and remain upright for 30 mins)
Osteonecrosis of jaw
Atypical stress fractures
Teriparatide
MOA:
Recombinant PTH analog given subcutaneously daily
Increase osteoblastic activity
Use:
Osteoporosis
Causes increase bone growth compared to antiresorptive therapies
Adv. effects:
Transient hypercalcemia
Allopurinol
Competitive inhibitor of xanthine oxidase
Decreases conversion of hypoxanthine and xanthine to urate.
Also used in lymphoma and leukemia to prevent tumor lysis-associated urate nephropathy
Increases concentrations of azathioprine and 6-MP (both normally metabolized by xanthine oxidase)
Use: Chronic gout
Febuxostat
Inhibits xanthine oxidase
Use: Chronic gout
Pegloticase
Recombinant uricase that catalyzes metabolism of uric acid to allantoin (a more water-soluble product).
Probenecid
Inhibits reabsorption of uric acid in proximal convoluted tubule (also inhibits secretion of penicillin)
Can precipitate uric acid calculi
Naproxen, Indomethacin (NSAIDs)
Do not give salicylates
All but the highest doses depress uric acid clearance.
Even high doses have only minor uricosuric activity
Use: Acute gout
Glucocorticoids
Oral, intra-articular or parenteral
Colchicine
Binds and stabilizes tubulin to inhibit microtubule polymerization, impairing neutrophil chemotaxis and degranulation
Use: Acute & prophylactic gout
Adv. effects:
GI
Etanercept
TNF-a inhibitors
Fusion protein (receptor for TNF-a + IgG1 Fc), produced by recombinant DNA
Use: Rheumatoid arthritis, Psoriasis, Ankylosing spondylitis
All TNF-a inhibitors predispose to infection (ex: reactivation of latent TB)
