NR 566 Week 4 Study Guide 2020– Johns Hopkins University School of Nursing ( Answer &Question 98% )
NR 566 Week 4 Study Guide
Chapter 25: Drugs Used
... [Show More] in Treating Inflammatory Processes
Gout medications
Drugs:
Anti-gout agents: allopurinol (Zyloprim), colchicine, and febuxostat (Uloric)
Uricosuric agents: probenecid (Benemid) and sulfinpyrazone (Anturane)
o Peak incidence 70 to 79 years old, more common in men than women
o Gout in women occurs exclusively post-menopausal and is associated with HTN, renal insufficiency, and diuretics
o Gout Syndrome: Caused by an alteration in purine metabolism: end product is uric acid
o Hyperuricemia and deposition of urate crystals in various tissues
o Four phases: asymptomatic hyperuricemia, acute gouty arthritis, inter-critical gout, and chronic tophaceous gout
o Those with asymptomatic hyperuricemia do not require treatment (diet and lifestyle changes)
o Acute gout is characterized by sudden onset of pain, erythema, limited ROM, and swelling of the involved joint
50% of cases involve the first metatarsal joint of the great toe
o Key elements in Tx include management of the acute pain and use of antigout and uricosuric agents
o Pain: NSAIDS and corticosteroids
Pharmacodynamics
Antigout Drugs (allopurinol, colchicine, and febuxostat)
o Act to reduce the inflammatory process or to prevent the synthesis of uric acid
o Allopurinol and febuxostat inhibit xanthine oxidase: enzyme responsible for conversion of hypoxanthine and xanthine to uric acid
o Allopurinol has a metabolite (alloxanthine): also an inhibitor of xanthine oxidase
o Allopurinol acts directly on purine metabolism, reducing the production of uric acid, without disrupting biosynthesis of vital purines
o Allopurinol and febuxostat are the only drugs that act directly on the pathophysiological cause of gout
o Allopurinol decreases both serum and urinary uric acid in 2 to 3 days: dose dependent
A week or more of Tx may be necessary before the full effects can be seen
o Febuxostat is used to treat hyperuricemia in patients with gout
o Goal is to have uric acid level of less than 6 mg/dL
o Can take 2 weeks or more to see the effects of febuxostat
o Colchicine: does not affect purine metabolism
o Binds to the microtubular proteins to interfere with the function of the mitotic spindles and inhibit migration of granulocytes to the inflamed area
o Reduces lactic acid production by granulocytes: decreases deposition of uric acid
o Interferes with kinin formation and reduces phagocytosis
o Taken together: these actions decrease the inflammatory response to the deposited urate crystals
o Relives pain in acute attack: not an analgesic
o Its prophylactic, suppressive effect helps reduce the incidence of acute attack and relives patient’s occasional residual pain and mild discomfort
Uricosuric drugs: probenecid (Benemid) and sulfinpyrazone (Anturane
o These drugs increase the rate of uric acid secretion in the urine
o Both drugs inhibit renal tubular reabsorption of urate and thus increase the renal excretion of uric acid and decrease serum uric acid levels.
o Effective uricosuria reduces the miscible urate pool, retards urate deposition, and promotes reabsorption of urate deposits
o Sulfinpyrazone competitively inhibits platelet prostaglandin synthesis: prevents platelet aggregation (antithrombotic effects)
o Both drugs lack anti-inflammatory activity
o Most useful in patients with reduced urinary excretion of uric acid
o Not intended for Tx of acute attacks [Show Less]