NSAIDs and Gout Flashcards
NSAIDs - MoA
Inhibition of prostaglandin synthesis by competitive cyclooxygenase (COX) inhibition
NSAIDs - Clinical use
Low dose: mild-moderate pain, antipyretic Higher doses: inflammation. Postop pain (often combined with opioid) Chronic pain
NSAIDs - Contraindications
Avoid treatment with two NSAIDs (increased GI bleeding risk).
Generally not recommended for second half of pregnancy
Previous severe hypersensitivity to salicylates (cross-sensitivity)
NSAIDs - Adverse
GI bleeding, peptic ulcers, renal & hepatic dysfunction. Lithium toxicity. Hyperkalemia Platelet inhibition Premature closure of ductus arteriosus
NSAIDs - Interactions
Inhibit renal excretion of lithium.
Reduced clearance of aminoglycosides & methotrexates.
Interfere with antihypertensive effect of: diuretics, β-adrenoceptor antagonists, angiotensin inhibitors & others.
Potassium-sparing diuretics: hyperkalemia
Salicylates - MoA
Nonspecific inhibition of COX
Salicylates - Clinical use
Pain, fever, inflammation
Prophylaxis for MI, stroke, thromboembolic disorders
Salicylates - Contraindications and Overdose treatment
Avoid in children: Reye syndrome (in virus infected children).
Overdose treatment: Vomiting IV sodium bicarbonate (alkalization of the urine, increases ionization and elimination) Fluids Electrolytes
Salicylates - Adverse
Reye syndrome
Salicylates - Interaction
Hypoglycemic effect alter antidiabetic drugs
Aspirin - MoA
Forms covalent, irreversible inhibition of COX in platelets
Nonspecific inh of COX in peripheral tissues and CNS
Aspirin - Clinical use
Analgesic
Antipyretic
Anti-inflammatory
Aspirin - Adverse
Aspirin toxicity
High dose:
Tinnitus (early sign of salicylate toxicity)
Hyperventilation
Fever, dehydration, severe metabolic acidosis
If not treated: Shock, coma, organ system failure, death
Hypoprothrombinemia – impairment of hemostatis and bleeding
Hypersensitivity – anaphylaxis (mostly pt with asthma, nasal polyps, chronic urticaria)
Symptoms of aspirin intolerance: vasomotor rhinitis, angioedema, urticaria
Aspirin - Interactions and contraindication
Adm with antacids: slows absorption rate
Contraindication:
Persons who have has severe hypersensitivity reaction to aspirin or another salicylate should not be treated with another type of NSAID (cross-sensitivity)
Ibuprofen - MoA
Reversible and nonselective inh of COX
Ibuprofen, Ketoprofen, Naproxen - Clinical use
Analgesic, antipyretic and anti-inflammatory effects
Low dose: mild pain & inflammation
Higher dose: arthritis
Ibuprofen - Special
Combo with H2 receptor antagonist famotidine for RA & OA (less GI ulcers)
Half-life: 2h
Ibuprofen - Adverse
GI irritation, nausea, dyspepsia, bleeding.
Long-term: PUD,
Hepatotoxicity, renal toxicity
Failure of ingesting adequate fluid: acute renal failure
Naproxen - Special
Combo with esomeprazole: arthritis, reduces risk of ulcers
Longer halflife (14h)
Acetaminophen - MoA
COX3 inhibitor
Acetaminophen - Clincal use
Mild fever & pain
Mild arthritis
Analgesic and antipyretic effects via inh of COX
Acetaminophen - Special consideration and Overdose treatment
Safe for children with viral inf.
Overdose treatment: acetylcysteine
Can be used with other NSAID of supplemental analgesia. Should be avoided.
Acetaminophen - Adverse
Fewer GI problems
Low doses ok in pregnancy for analgesia & antipyresis
High dose: hepatic necrosis, hepatotoxicity
Long-term use: Increased risk of renal dysfunction
Acetaminophen - Interactions
Small amount converted by CYT P-450 to potentially hepatotoxic quinone intermediate
Patients at risk for hepatotoxicity (f.ex. overdose): given acetylcysteine (conjugates quinone and renders it harmless)
Indomethacin - Clinical use
Reserved for moderate/severe infl disorders
Patent ductus arteriosus (indomethacin inh synthesis of prostaglandins and causes the closure)
Indomethacin - Adverse
Nephrotoxicity with triamterene
Highest incidence of GI and CNS side effects
Hematologic toxicity
Indomethacin - Interaction
Reduces natriuretic effect of diuretics.
With triamterene: nephrotoxicity
Sulindac - MoA
Prodrug converted to active sulfide metabolite. Parent compound sulindac sulfoxide is inactive in COX inh
Sulindac - Clinical use
RA
Adenomas in polyp disease
Ketorolac - Clinical use
Analgesic activity
Post-op moderate pain in dentistry
Allergic conjunctivitis
Post-op ocular infl.
Ketorolac - Special consideration and contraindications
Treatment limited to 5 days.
Caution in pt with renal/hepatic disease
Ketorolac - Adverse
Fewer GI and CNS effects than opioids.
Hematologic toxicity
Increased risk of renal or hepatic impairment
Piroxicam - Clinical use
Anti-inflammatory
Chronic RA treatment
Piroxicam - Special
Long half-life (50h)
Nabumetone - MoA
Weak COX inhibitory activity in vitro, but converted to active metabolites with potent inhibition in vivo
Etodolac, meloxicam - MoA
More selective for COX-2 than typical NSAIDs
Diclofenac - Clinical use
Osteoarthritis
Selective COX-2 inhibitors
Celecoxib
Rofecoxib (Removed from market)
Valdecoxib (Removed from market)
Selective COX-2 inhibitors - MoA
Potent anti-inflammatory action
Selective COX-2 inhibitors - Special
Decreased risk of cancer (esp colon cancer)
Celecoxib - Clinical use
Rheumatoid arthritis
Osteoarthritis
Celecoxib - MoA
Analgesic, antipyretic, antiinflammatory
Celecoxib - Adverse
Increased risk of cardiovascular events
Low incidence: diarrhea, dyspepsia, abd pain
Celecoxib - Interactions
Metabolized by CYT P-450, excreted in feces and urine
Metabolism is inhibited & increased serum levels by fluconazole, fluvastatin, zafirlukast.
Uricosuric drugs
Probenecid
Sulfinpyrazone
Lesinurad
Uricosuric drugs - Clinical use
Prevent gout attacks in persons who under-excrete uric acid.
Probenecid - MoA
Increases excretion of uric acid by competitive inhibition of uric acid reabsorption
Probenecid - Interactions
Aspirin and salicylates: interfere with the uricosuric effect.
High dose of salicylates: inh uric acid reabsorption
Low doses of salicylates: inh uric acid secretion
Sulfinpyrazone - MoA
Complete inhibition of urate reabsorption, increasing uric acid excretion
Sulfinpyrazone - Adverse
GI, renal and hematologic adverse effects
Lesinurad - MoA
Reduces uric acid levels by inh the function of transporters responsible for uric acid reabsorption, uric acid transporter 1 and organic anion transporter 4.
Xanthiine oxidase inhibitors
Allopurinol and Febuxostat
Xanthiine oxidase inhibitors - MoA
Decreases production of uric acid
Xanthiine oxidase inhibitors - Clinical use
Prevent gout attacks in people who overproduce uric acid.
Prevent hyperuricemia and gout in persons having cancer chemotherapy and whose rate of purine catabolism is high.
Allopurinol - MoA
Competitive inhibitor of xanthine oxidase
Converted to active metabolite oxypurinol in the liver.
Decrease in uric acid excretion and corresponding increase in urinary excretion of hypoxanthine.
Allopurinol - Clincal use
Hyperuricemia and gout in cancer patients with high purine catabolism
Prevent the occurrence or progression or both gouty arthritis and urate nephropathy
Allopurinol - Adverse
Nausea, vomiting, hepatitis, skin rashes, hypersensitivity.
Allopurinol - Interactions
Inhibits catabolism of azathioprine and mercaptopurine
Febuxostat - MoA
Competitive inhibitor of xanthine oxidase
Febuxostat - Adverse
Liver enzyme elevations, nausea, arthralgia, rash
Catabolic enzyme preparations
Pegloticase and Rasburicase
Catabolic enzyme preparations - MoA
Reverse hyperuricemia
Pegloticase - Clinical use
Refractory chronic gout
Pegloticase - Adverse
Life-threatening allergic reactions
Rasburicase - Clinical use
ONLY: initial management of plasma uric acid in pediatric and adults with leukemia, lymphoma and solid tumor malignancies who are receiving anticancer therapy
Rasburicase - Adverse
Allergic reactions
Drugs for treating gout attacks
Indomethacin and Clochicine
Indomethacin - MoA
Anti-inflammatory drug for rapid relief of pain
Clochicine - MoA
Disrupting microtubules and inh of inflammatory leukocyte motility –> blocking their ability to cause urate crystal-induced joint inflammation.
Clochicine - Adverse
Nausea, vomiting, diarrhea, abdominal cramps
Indomethacin and Clochicine - Clinical use
Acute gout