5 - Arthritis And Gout Flashcards
Herbenden Nodes, PIP’s and DIP’s affected, think:
Osteoarthritis
APAP - MOA (for OA):
No significant anti-inflammatory effect
Acts centrally as an analgesic and antipyretic
APAP - clinical use in OA:
1st line for pain management of OA
Efficacy - similar pain relief to NSAID, less ADR’s
NSAID’s - clinical use in OA:
Anti-inflammatory and analgesic
Lower doses for analgesia, higher doses for inflammation
Topical NSAID’s for OA - who uses it
Knee-only arthritis
What is Diclofenac Gel 1%?
Topical NSAID for knee or hand osteoarthritis
Topical Salicylates (Bengay, Adpercreme, etc) for OA - MOA?
Local inhibition of COX-2 enzymes
Capsaicin in OA - MOA?
Releases and immediately depletes substance P from afferent nociceptive nerve fibers
Caspaicin - clinical use:
Muscle/joint pain
Neuropathic pain associated with diabetes or postherpatic neuralgia
Must use regularly 4x a day for maximum effect
Intra-articular corticosteroids - MOA:
decreases inflammation by suppression of
migration of polymorphonuclear leukocytes and reversal of increased capillary permeability
Intra-articular corticosteroids - clinical use:
OA/RA
Not to exceed 3 to 4 injections per year (significant degradation of cartilage)
Hyaluronate Injections - proposed MOA:
Hyaluronic acid is a viscous substance in synovial fluid that lubricates the joint
Hyaluronic injection - clinical use:
Not generally recommended
May try in patients who fail other therapies
Opioids for OA - for pt’s who:
Get no relief from APAP, NSAID’s, or topical therapy
Tramadol (Ultram) C-IV - MOA:
Partial Mu receptor agonist
Serotonin and norepinephrine reuptake inhibitor
Tramadol - clinical use in OA:
Moderate to severe pain that is not controlled by NSAID’s or APAP
Pt’s who can’t take NSAIDS
Tramadol - AE’s
Increased risk of serotonin syndrome
What labs tests will be positive in RA?
Rheumatoid factor (RF)
Elevated C-reactive protein (CRP)
Elevated erythrocyte sedimentation rate (ESR)
NSAID’s - use in RA?
Immediate relief of pain and inflammation
Preferred as ADJUNCT to DMARDs while they start to kick in
Preferred NSAID’s for RA:
Ibuprofen
Meloxicam
Nabumetone
Naproxen
Corticosteroids for RA?
Methylprednisolone IV
Prednisolone PO
Prednisone PO
What are DMARDs?
Disease-Modifying Anti-Rheumatic Drugs
Takes weeks to months to see full benefit
Screen pt’s for Hep B/C and TB prior to starting therapy
What are the four traditional DMARDs?
Methotrexate
Leflunomide
Hydroxychloroquine
Sulfasalazine
What is the preferred DMARD to start with according to ACR?
Methotrexate
Methotrexate - MOA?
Dihydrofolate reductase inhibitor
Interferes with DNA synthesis
Inhibits fast-growing cells
Leads to anti-inflammatory and, unfortunately, IMMUNOSUPPRESSIVE effects
Methotrexate - clinical use:
Preferred DMARD for RA tx
Also tx’s joint symptoms of psoriatic arthritis
Methotrexate - AE’s?
GI
Leukopenia (keep an eye on CBC, platelets), hepatic cirrhosis (keep an eye on AST/ALT)
Methotrexate - pregnancy cat?
X
What is the methotrexate toxicity reversal agent?
Leucovorin (supplies the necessary cofactor blocked by methotrexate)
Leflunomide - MOA:
PRODRUG
Inhibits pyrimidine synthesis
Antiproliferative, anti-inflammatory
Leflunomide - pharmacokinetics:
Detectable levels 2 years after stopping medication
If you need to rapidly clear the drug you can use CHOLESTYRAMINE
Leflunomide - AE’s?
Severe liver injury
Peripheral neuropathy
Leflunomide - pregnancy cat?
X
Hydroxychloroquine - MOA:
Inhibits locomotion of neutrophils chemotaxis of eosinophils
Hydroxychloroquine - clinical use:
Anti-malarial (only labelled use)
RA and SLE (off-label)
Sulfasalazine - MOA:
PRODRUG
Cleaved by bacteria in the colon and 5-aminosalicylic acid
Decreased production of IgA and IgM
Sulfasalazine - clinical use:
Used for mild RA
Not as effective as methotrexate
Also used for ulcerative colitis
Sulfasalazine - drug interactions
ABX can cause decreased absorption
Sulfasalzine binds iron in the GI tract
Can displace warfarin
All biologic DMARD’s can increase risk of:
Infection
Black box warning for biologic DMARD’s:
All anti-TNF-alpha can cause increased lymphoproliferative cancers in peds and adults
Etanercept typically for pt’s who:
Have failed methotrexate
MOA for biologic DMARD’s:
Block the pro-inflammatory cytokines TNFa, interleukin, or bind on target receptors on T-cells to prevent the co-stimulation needed to fully activate T-cells
Predisposing factors for gout:
- Diet - meat, fatty food, alcohol, high-fructose
2. Medical - DM, HTN, HLP
What is the serum urate target in tx of gout:
6mg/mL
Non-pharm management of gout:
Weight loss Healthy diet Exercise Smoking cessation Adequate hydration
3 primary classes of meds for acute gout:
NSAID’s
Colchicine
Glucocorticoids
What are the three primary med classes for urate-lowering (chronic suppression):
- Xanthine Oxidase Inhibitors
- Uricosuric agents
- Uricase
Most appropriate first-line drugs for acute gout attack?
NSAID’s and Colchicine
Colchicine only if initiated within ___ hours of attack onset
36
NSAID’s plus corticosteroids are NOT recommended in acute gout due to:
GI ADE’s
Which NSAID’S are FDA approved for gout?
Naproxen
Indomethacin
Sulindac
Colchicine - MOA:
Binds to intracellular protein tubulin; prevents activation, degranulation, and migration of neutrophils associated with mediating some gout symptoms
Colchicine - clinical use:
Treatment of gout flares
Prophylaxis of gout flares
Colchicine - drug interactions?
Significant - CYP3A4
Urate-Lowering Therapy (ULT) - clinical use:
Chronic management of hyperuricemia
Tophi present
Two or more attacks per year
CKD
Past urolithiasis
What is the first-line ULT?
Xanthine Oxidase Inhibitor - Allopurinol or Febuxostat
XOI - MOA:
Inhibits uric acid synthesis by inhibiting xanthine oxidase (therefore no conversion to uric acid)
Which XOI has a higher risk of thromboembolic events?
Febuxostat
Uricosuric Agents - MOA:
Weak organic acids that promote renal clearance of uric acid by inhibiting proximal tubule urate-anion exchangers that mediate urate reabsorption
In english -> stop reabsorption of urate
What type of meds are Probenecid and Lesinurad?
Uricosuric Agents
What type of meds of Pegloticase and Rasburicase?
Uricase
Uricase - MOA:
It’s an enzyme that humans don’t normally have
Lowers serum uric acid
Clinical use of uricase:
Severe gout disease refractory to traditional ULT’s
What can uricase exacerbate?
HF
What is uricase contraindicated in?
G6PD deficiency