Pain Medications Flashcards
Aspirin
-COX selectivity
-Effect
-Disposition/Elimination
-inhibits COX in all tissues (COX-1>COX-2)
-decrease kinins, stabilizes lysosomes, removes energy for oxidative phosphorylation, irreversible platelet defects by suppressing TxA
-50-70% bound to albumin, hepatic elimination, renal excretion
Asprin
-adverse reaction
-Dog vs cats
-chondrotoxic (decreases GAG)
-hepatoxicity, nephrotoxicity
Dogs: dose-dependent gastric ulceration
Cats: glucuronidation deficient
Flunixin Meglumine
-COX selectivity
-Effect
-Dog vs cats
-nonselective COX inhibitor, approved for horses
-visceral pain, anti-endotoxic effects in septic shock
Dogs: visceral or PO pain
Cats: enterohepatic circulation
Ibuprofen
-COX selectivity
-effect
-reactions
-Dog vs cats
-propionic acid derivative, nonselective COX inhibitor
-anti-inflammatory, less effective than aspirin
-LEAST SAFE NSAID in dogs –> GI signs, death
-Dogs, AVOID
Ketoprofen (UK)
-COX selectivity
-effects
-Disposition/Elimination
-propionic aci derivative (COX 1 selective)
-Strong anti-inflammatory, analgesic, and antipyretic
-inhibits bradykinin
-99% protein bound, hepatic metabolism, urine excretion
Ketoprofen (UK)
-adverse reactions
Dogs vs cats
-Upper GI upset
-CNS (headaches, dizziness)
-Nephritis
Dogs: analgesia for 12-24 hr
Cats: rapid antipyretic, analgesia 8h
Ketorolac
-COX selectivity
-effects
-adverse reactions
-Carboxylic acid derivative
-Cox inhibitor (COX-1>COX2)
-moderately effective as anti-inflammatory, potent analgesic
-GI upset
Naproxen
-COX selective
-Disposition/elimination
-Dogs vs Cats
-proprionic acid derivative, non-selective COX inhibitor
-extensive enterohepatic circulation
Dogs: AVOID, GI toxicity, long half life
Phenylbutazone
-COX selective
-effects
-disposition/elimination
-pyrazolidine, nonselective COX inhbitor (slightly COX 2 > COX 1)
-decreased pain and swelling due to inhbition of PGH synthase and prostacyclin synthase
-hepatic metabolism
-excretion in urine
Phenylbutazone
-adverse effects
-Dogs vs cats
-Chondrodistructive effects
-hemorrahge, biliary stasis, hepatitis, renal failure, blood dyscrasias
Dogs: more tolerant
Cats: AVOID, high incident of toxicity with 80% mortality, toxicity in bone marrow
Piroxicam
-COX selective
-effects
-Dogs vs cats
Non-selective COX inhibitor
-potent anti-inflammatory, reduces bladder TCC
Dogs: gastric lesions and renal papillary necrosis
Cats: shorter half life
Tolfenamic Acid (UK)
-COX selective
-effects
-disposition/elimination
-Anthranilic NSAID, nonslective COX inhibitor
-anti-inflammatory and antipyretic
-enterohepatic circulation
Tolfenamic Acid (UK)
-adverse effect
Dogs vs cats
-use only for 3 days and can be repeated weekly
Dogs: approved for long term use
Cats: approved for short term use
Indomethacin
-COX selective
-effects
-adverse effects
-indole acetic-acid derivative, non-selective COX inhibitor
-abate inflammatory response to indolic hormones (serotonin and tryptophan)
-CNS side effects in humans
-Dogs: GI hemorrhage from gastric ulcers
Carprofen
-COX selective
-Effects
-Disposition and elimination
COX 2 selective
-MOA not understood, inhibit eicosanoid synthesis, antipyretic, analgesic, anti-inflammatory
-highly protein bound, hepatic metabolism, 70-80% excreted in feces
Carprofen
-adverse reactions
-Dogs vs cats
-minimal side effects and limited to GI toxicity due to favorable COX 1:COX 2 ratio
-hepatotoxicity, nephrotoxicity, high doses inhibit polysulfated glycosaminoglycan synthesis
Dogs: safe
Cats: half life twice as long, COX 2 selectivity not proven
Vedaprofen
-COX selectivity
-Adverse reactions
-COX 2 selective
-safety comparable to meloxicam
-GI side effects in 11-12%
Mavacoxib (UK)
-COX selectivity
-Disposition/elimination
-Dogs vs cats
-COX 2 selective
-very slow clearance, therapeutic concentrations maintained for 1 month
-half life 40 days
-biliary tract elimination
Dogs: treatment cycle not exceeds 6.5 months
Deracoxib
-COX selectivity
-effect
-Disposition/elimination
-COX 2 selective, but loses specificity at higher concentrations
-limited efficacy in dogs
-half life 3h
Deracoxib
-adverse effects
Dogs vs cats
-GI toxicity
-may cause sulfonamide related reactions–> KCS
-Dogs: not evaluated in dogs <4mths, not evaluated in pregnant or lactating animals
Firocoxib
-COX selective
-effects
-disposition/elimination
-HIGHLY COX 2 selective
-analgesia, anti-inflammatory
-large volume of distribution and rapid clearance —> SID dosing
Firocoxib
-adverse effects
-Dogs vs cats
-fatty liver in young dogs
-juvenile polyarthrits, thrombocytopenia, decreased albumin and elevated liver enzymes
-Dogs: avoid in <6mth
Robenacoxib
-COX selective
-effects
-disposition/elimination
-COX 2 selective
-analgesia, anti-inflammatory
-great targeting to sites of inflammation–> SID dosing
-efficacy HIGH when given WITHOUT food, hepatic metabolism, primarily biliary excretion
Meloxicam
-COX selective
-effects
-disposition/elimination
-COX 2 selective
-analgesia, anti-inflammatory
-potent (low dosing)
-100% oral bioavailability
Meloxicam
-adverse effects
Dogs vs cats
-Low GI and renal toxicity
-GI perforation when given with underlying GI disease
- Dogs: safe and effective for OA
-Cats: shorter half life, narrow therapeutic margin with renal disease
Cats: licensed for long term use in cats with OA in Europe, Australia, NZ
Etodolac
-COX selective
-effects
-disposition/elimination
-Carboxylic acid (indole), COX 1 sparing
-Primarily inhibits COX 1
-anti-inflammatory effects to interference with macrophage chemotaxis, anti-inflammatory by inhibiting chondrocyte and synoviocyte synthesis of PGE-2
-food prolongs elimination, biliary excretion and enterohepatic circulation
Etodolac
-adverse effects
Dogs vs cats
-GI toxicity
-decreased TP, albumin, and globulin
-KCS
Dogs: not used, caution with hepatic, renal or hematologic dysfunction
Acetaminophen
-MOA
-effects
Dogs vs cats
-NO COX INHIBITION
-poor anti-inflammatory
-potent analgesic (cannabinoid receptors) and antipyretic ,
-stimulate inhibitor pain by activating serotonin receptors
-interferes with endoperoxide intermediates of AA conversion
Dogs: safe with no renal or gastric injury, depression, MetHb, vomiting
Cats: NOT TO USE, requires glucuronidation, form toxic metabolites –> metHb and hepatic necrosis
Amantadine
-MOA
-Effects
Dogs vs cats
-NMDA receptor antagonist
-neurobiologic changes underlying sensory disturbances with prolonged inflammatory pain
-Dogs: benefits when given with meloxicam
Gabapentin
-MOA
-effects
-disposition/elimination
-adverse effects
-GABA analog, suspect involving voltage gated calcium channels
-neuropathic pain
-excreted by kidney
-dizziness, drowsiness, peripheral edema
Codeine (methylmorphine)
-MOA
-effect
-disposition/elimination
-natural alkaloid found in opium
-no reports on OA in dogs,
-metabolized in vivo to morphine (5-10%), codeine -6-glucuronide (70%), norcodeine (10%) , hydromorphone (1%)
Corticosteroids
-effects
-adverse effects
-IA injections for joint inflammation with minor systemic absorption
-long lasting: methylprednisone acetate, triamcinolong acetonide, triamcinolone hexacetonide
-with multiple uses may cause harmful effects on cartilage
Polysulfate glycosaminoglycans (adequan)
-MOA
-effects
-Dogs vs cats
-MOA unknown
-maintain chondrocyte viability, stimulates chondrocyte division and protects against ECM degradation
-Dogs: IM twice weekly for 4 weeks
Chondroitin sulfate
-MOA
-effects
-disposition/elimination
-MOA unknown
-not to used in intact articular cartilage
-anti-inflammatory effect, reduce neutrophil and macrophage infiltration in soft tissues
-5% bioavailability in dogs after single dose
Glucosamine sulfate or hydrochloride
-MOA
-effects
-disposition/elimination
-MOA unknown
-may influence chondrocyte metabolism by increases glycosaminoglycan synthesis and stimulating proteoglycan core protein production
-weak anti-inflammatory
-90% absorbed
Essential fatty acids
-MOA
-effects
-disposition/elimination
-compete for incorportation into phospholides as substrains for COX-1, COX 2, and 5-lipoxygenase
-N-3: antiinflammatory: reduce mRNA levels for COX2
-N-6: inflammatory -promotes produciton of inflammatory prostoglandins, leukotrienes, and thromboxanes
-Eicosapentaenoic acid most effect n-3 anti-inflammatory fatty acids
Zileuton
-MOA
-Effects
-Adverse effects
-selective 5-LOX inhibitor
-limited efficacy
-hepatotoxicity
Tepoxalin
-MOA
-effects
-disposition/elimination
-Nonselective COX and LOX inhibitor
-Anti-inflammatory (inhibits COX 1, COX2, 5-LOX)
-Analgesic- inhibits IL1 and NFKappaB
-effect on leukotriene activity may be responsible for protection against GI toxicity
-enhance absorption with food, highly protein bound, hepatic metabolism, eliminated in feces
Tepoxalin
-adverse effects
Dogs vs cats
-GI toxicity in 10%
-Hepatotoxicity-inhibit other redox-active systems
-Dogs: ameliorate degradation of collagen
-Cats: well tolerated SID, antipyretic, analgesic
Licofelone
-MOA
-effects
-dogs vs cats
-di-tert butylphenol
-impairs PDE production, prevent formaiton of LTB4, anti-oxidant
Dogs: not approved for use
Pentoxifylline
-MOA
-effects
-disposition/elimination
-leukotriene receptor anatagonist
-anti-inflammatory, inhibits IL1 IL6 TNFa
-**increases flexibility of RBCs and decreases blood viscosity
-hepatic metabolism
