Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. Chapter 74 Drug Therapy of Gout.

Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc.

Chapter 74

Drug Therapy of Gout

Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 2

Gout

Recurrent inflammatory disorder Seen mainly in men

Hyperuricemia Uric acid level greater than 7 mg/dL in men or greater than

6 mg/dL in women Uric acid crystals deposited in joints

Episodes of severe joint pain (typically in large toe) Causes

Excessive production of uric acid Impaired renal excretion of uric acid


Overview of Drug Therapy

Short-term to relieve symptoms of attack Infrequent flare-ups (fewer than 3 times/yr) NSAIDs: first-line agents Glucocorticoids also used

Long-term to lower blood levels of uric acid 3 or more times per year Uricosuric drugs


NSAIDs

Agents of first choice for gouty arthritis Better tolerated and more predictable than

colchicine Relief should be within 24 hours; swelling

subsides over the next few days Adverse effects

GI ulceration, decreased renal function, fluid retention, increased risk of cardiovascular events


NSAIDs

Indomethacin (Indocin) Naproxen (Naprosyn) Diclofenac (Voltaren)


Glucocorticoids

Highly effective in relieving pain Useful for patients who are hypersensitive to,

are unresponsive to, or have medical conditions that contraindicate the use of NSAIDs

Avoid in patients prone to hyperglycemia


Colchicine

Anti-inflammatory agent No longer the first-line drug Now reserved for patients who are

unresponsive/intolerant to safer agents Uses

Treats acute gouty attack Reduces incidences of attack Aborts an impending attack


Colchicine

Mechanism of action Pharmacokinetics Adverse effects

Gastrointestinal Myelosuppression Myopathy

Drug interaction


Drug Therapy for Hyperuricemia

Goals of therapy Promote dissolution of urate crystals Prevent new crystal formation Prevent disease progression Reduce the frequency of acute attacks Improve quality of life

Note: Because these drugs have no analgesic or anti-inflammatory actions, they are not useful in an acute gouty attack


Drug Therapy for Hyperuricemia

Allopurinol (Zyloprim) Inhibits uric acid formation

Febuxostat (Uloric) Inhibits uric acid formation

Probenecid (Benemid) Increases uric acid excretion

Sulfinpyrazone (Anturane) Increases uric acid excretion


Allopurinol (Zyloprim)

Reduces blood levels of uric acid Uses

Chronic tophaceous gout Hyperuricemia due to chemotherapy

Adverse effects (generally well tolerated) Hypersensitivity syndrome Gastrointestinal effects Neurologic effects


Fig. 74–1. Reduction of uric acid formation by allopurinol.


Febuxostat (Uloric)

Reduces blood levels of uric acid Uses

Chronic tophaceous gout Adverse effects (uncommon)

Liver function abnormalities Nausea Arthralgia Rash


Probenecid (Generic Only)

Acts on renal tubules to inhibit reabsorption of uric acid Prevents formation of new tophi and helps existing

tophi decrease May exacerbate acute episodes of gout

Add indomethacin for relief Adverse effects

Usually well tolerated, but mild GI effects occasionally occur; take with food

Drug interactions

Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. Chapter 74 Drug Therapy of Gout.

Documents

Transcript of Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. Chapter 74 Drug Therapy of Gout.