Antipyretic/Analgesics

Question 1

Aspirin (Prototype)

Answer 1

• Acetylsalicylic acid/ASA à salicylic acid •Irreversibly acetylates COX – inhibitor
• Inhibits platelet aggregation (low dose) [Thromboembolism, Atherosclerosis] & decr PG-mediated potentiation of pain transduction in nociceptive neurons and PG-mediated elevation of body temperature [Analgesia,Antipyretic, Anti-Inflammation]
• PO, 160-320 mg/day for maximal anti-thrombotic activity, Zero-order
• AEs: Hemorrhage; single dose doubles bleeding time for 4-7 days; Peptic ulceration uncommon with anti-thrombotic doses; GI bleeding
• Aspirin sensitivity: Acute toxicity: salicylism can be fatal; abdominal pain, hyperventilation, acid-base disturbances, dehydration, tinnitus, confusion, CNS depression; Chronic toxicity: hyperthermia, compound analgesics implicated in analgesic nephropathy (acute renal insufficiency); Reyes Syndrome, Hypertension, “allergy” = vasomotor rhinitis, uticaria, laryngeal edema, shock, bronchial asthma (cross-sensitivity to other NSAIDs);

Question 2

Ibuprofen (Proprionic Acid)

Answer 2

• Reversibly inhibits COX (decr PGs)
• Also used to close patent ductus arteriosus; analgesia, fever, inflammation
• Lower incidence of bleeding
• **Common AEs
• AKA Motrin, Advil

Question 3

Naproxen (Proprionic Acid)

Answer 3

• Reversibly inhibits COX (decr PGs)
• Longer t1/2 - BID-QD
• analgesia, fever, inflammation
• **Common AEs
• AKA Naprosyn, Aleve

Question 4

Celecoxib

Answer 4

• Specific inhibits COX-2 (not more effective)
• $$$$
• Analgesia, fever, inflammation
• Less peptic ulceration and bleeding. Increased risk of cardiac death.
• AKA Celebrex

Question 5

Acetaminophen

Answer 5

• Weak PG-synthesis inhibitor (COX3?)
• NOT anti-inflammatory or antiplatelet
• Analgesia; Fever
• AEs: Toxicity: Acute: hepatic failure, renal failure, thrombocytopenia, pancreatitis treated with N-acetylcysteine. Chronic: compound analgesics implicated in analgesic nephropathy; initially GI symptoms
• Safest for kids (liquid available)
• AKA Tylenol

Question 6

N-Acetylcysteine

Answer 6

• Antidote [Acetaminophen Poisoning]
• Provides –SH groups, substitutes for hepatic glutathione [suicidal/accidental acetaminophen overdose]
• AKA Mucomyst

Question 7

Indomethacin

Answer 7

• Reversibly inhibits COX (decr PGs), maybe also PLA2
• Use now restricted to Gout; [close ductus arteriosus-older, Analgesia, Fever, Inflamm]
• **Common AEs
• AKA Indocin

Question 8

Diclofenac Sodium

Answer 8

• Reversibly inhibits COX (decr PGs)
• Also arthritis, Analgesia, Fever
• Concentrates in synovial fluid

AKA Voltaren, Arthrot

Question 9

Keterolac

Answer 9

• Reversibly inhibits COX (decr PGs)
• Post-op pain, analgesia; $$$$
• PO, IM, IV or SC
• AKA Toradol

Question 10

Piroxicam

Answer 10

• Non-selective COX inhibitor
• Decreases PMN migration and lymphocyte activation.
• Once daily administration
• Mostly for RA [analgesia, fever, inflamm]
• AKA Feldene

Question 11

**Common AEs for Ibuprofen, Naproxen, & Indomethacin

Answer 11

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GI complaints [ulcers, bleeding], rash, pruritus, tinnitus, dizziness, headache, fluid retention, cardiovascular.

Rare: acute renal failure, interstitial nephritis, nephrotic syndrome. Late pregaancy – premature closing of ductus arteriosis.

Combos of NSAIDs not safe (Excedrin)<!--EndFragment-->